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[Objective] The present paper aimed to investigate the mechanism of yield and carbon assimilates metabolism in cotton varieties of different genotypes in response to low phosphorus stress, and to provide a theoretical basis for the physiological regulation of cotton yield and quality under low phosphorus stress in production. (Method) In the study, a pot experiment was conducted with low phosphorus tolerant genotypes (BX014 and LuYuan343) and low phosphorus sensitive genotypes (FJA and DLNTDH), and low phosphorus (P1, 15 mg/kg), medium phosphorus (P2, 50 mg/kg), normal phosphorus (P3, 150 mg/kg), and high phosphorus (P4, 300 mg/kg) were used as the experimental materials. Four treatments were used to study the effects of different phosphorus application levels on dry weight, phosphorus uptake and utilization, yield traits, and carbohydrate metabolism of cotton bolls and their correlation between carbon assimilates metabolizing enzyme activities and yield. [Result] (i) Under low phosphorus stress, the dry weight accumulation of different organs, phosphorus accumulation, plant height, number of fruiting branches, number of fruiting nodes, number of bolls, weight of bolls, seed cotton yield, lint yield and clothing fraction of cotton would be significantly reduced, while the phosphorus utilization efficiency and boll abscission rate would be significantly increased, and there was a significant reciprocal effect between different phosphorus treatments and varieties. (ii) Carbohydrate content in boll-opposed leaves was the key substance in response to low phosphorus stress; Under low phosphorus treatment, with the increase of phosphorus content, cotton boll-opposed leaves sucrose and soluble sugar content generally showed a decreasing trend, and the activities of phospho-sucrose synthetase (SPS) and sucrose synthetase (SuSy) showed a tendency to increase firstly and then decrease. (iii) Under P1, P2 and P4 treatments, the cotton dry weight, phosphorus accumulation, phosphorus utilization efficiency and yield indexes of the low phosphorus tolerant genotypes were significantly higher than those of the low phosphorus sensitive genotypes, and the response to low phosphorus stress was not uniform, showing strong low phosphorus tolerance; And the activities of SPS and SuSy were significantly higher than those of the low phosphorus sensitive genotypes, and the difference in the enzyme activities might be one of the reasons for the low phosphorus tolerance of low phosphorus tolerant genotypes. The differences in enzyme activities may be one of the reasons for low phosphorus tolerance in low phosphorus tolerant genotypes. (iv) The correlation analysis of the traits showed that lint yield was extremely significant positive correlated with boll weight (correlation coefficient was 0.95), SPS (correlation coefficient was 0.96) and SuSy activity (correlation coefficient was 0.99), respectively. [Conclusion] Higher SPS and SuSy activities in the opposite leaves of cotton bolls of low phosphorus tolerant genotypes under low phosphorus stress maintain the ability of sucrose synthesis, which in turn promotes the redistribution of sugar, thus ensuring the production and accumulation of dry matter under low phosphorus conditions and thus increasing lint yield. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to investigate the effect of organic liquid fertilizer replacing some chemical fertilizer on growth characteristics, yield and quality of drip irrigated cotton. [Method] A field experiment was conducted during 2021-2022. Five treatments were set up in the experiment, including conventional fertilizer application alone (pure N 330 kg/hm², P2O5 180 kg/hm², K2O 120 kg hm²) (CF), 60% conventional fertilizer + 225 L/hm² alginate stock solution + 150 L/hm² liguo concentrated solution (LF1), 60% conventional fertilizer + 450 L/hm² alginate stock solution + 300 L/hm² liguo concentrated solution (LF2), 60% conventional fertilizer + 675 L/hm² alginate stock solution + 450 L/hm² liguo concentrated solution (LF3), and 60% conventional fertilizer + 675 L/hm² alginate stock solution + 450 L/hm² liguo concentrated solution (LF4). [Result] Dry matter accumulation and the maximum growth rate of dry matter increased with the liquid fertilizer supply rising. The maximum growth rate of dry matter of LF3 was 2.99% lower than CF, and LF4 was 7.34% higher than CF. Leaf area index (LAI) and SPAD values increased with the increase of liquid fertilizer dosage. Except for the bud stage, LAI in LFI and LF2 were significantly lower than CF, LF3 and CF were not significantly different, and LF4 was significantly higher than CF. SPAD values in LF1 and LF2 were significantly lower than CF, while there was no significant difference among LF3, LF4 and CF. In the flowering and boll stage, the net photosynthetic rate, transpiration rate and stomatal conductance increased with the increase of liquid fertilizer dosage, but intercellular CO2 concentration decreased with the increase of liquid fertilizer dosage. Number of bolls, boll weight and yield increased with the increase of liquid fertilizer dosage, LF1 and LF2 were significantly lower than CF, while there was no significant difference among LF3, LF4 and CF. Yield of LF1, LF2, LF3, LF4 and CF were 6012.5, 6528.5, 7274.5, 7568.5 and 7383 kg/hm², respectively. Fiber length and strength increased with the increase of liquid fertilizer dosage, but there was no significant difference among LF3, LF4 and CF. Micronaire decreased with the increase of liquid fertilizer dosage. There was no significant change between other treatments and CF, except for the significant difference between LF1 and CF. [Conclusion] Moderate amount of organic liquid fertilizer replacing some chemical fertilizer can promote the growth and development of cotton, increase yield appropriately and improve quality. Considering all indicators together, the optimum treatment is LF3 in the study. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to investigate the effect of super absorbent polymers (SAP) on soil biological activities, and dry rubber yield of rubber plantations and find out the optimal application dosage for rubber plantions of dorught-prone regions. This can provide some theoretical basis for the rubber tree drought resistance cultivation technology. [Method] A fifteen-year-old rubber plantion with the clone Reyan 7-33-97 was used to set out a field randomized block experiment and compare the application of different dosages of SAP (0, 60, 120, 180, 300 g/tree) on soil moisture, nutrients, microbial quantity, enzyme activities and the dry rubber yield of the rubber plantation. [Result] The application of super absorbent polymers increased the soil water content and available nutrient content of rubber plantations, but it had no effect on soil pH. At the same time, it significantly promoted the soil bacteria quantity, actinomycetes quantity and total microorganisms, but did not change the overall proportion of bacteria, actinomycetes and fungi in the soil. Soil enzyme activity and rubber latex yield showed a unimodal curve trend with the increase of SAP dosage. The soil bacteria quantity, actinomycetes quantity, soil urease acvitity, invertase acvitity, catalase acvitity, ammonia nitrogen content, available phosphorus content and the yield of dry rubber showed a trend of firstly increase and then decrease with the increase of SAP amount. The T2 treatment was the most effective, in which the soil microorganisms, enzymatic activity and dry rubber yield showed the best. Compared with CK, the quantity of soil bacteria and actinomycetes increased by 346.42% and 191.48%, respectively, while the quantity of soil fungi decreased by 15.31%, and the soil urease activity, invertase activity, and catalase activity increased by 40.01% and 15.74%, 31.44%, respectively, and the yield of the latex increased by 11.99%. [Conclusion] The recommended SAP applicationdosage for the tapping rubber trees is 120 g/tree, which is beneficial to the increase of soil water content, soil microorganisms quantity and soil nutrient contents, as well the promotion of dry rubber yield. [ABSTRACT FROM AUTHOR]

【Objective】 The present paper aimed to investigate the comprehensive effects of irrigation amount on soil enzyme activity, yield, quality and nutrient utilization of pepper in Sichuan Basin, and propose an appropriate irrigation amount. 【Method】 The pepper variety of Xingshuzhoula 3 was used as the experiment material. Four irrigation amount treatments were set, and the soil volumetric moisture content was controlled respectively at 35%-40% (T1), 45%-50% (T2), 55%-60% (T3), 65%-70% (T4). The soil urease, neutral phosphatase, sucrase β-Glucosidase activity and catalase activity such as yield, quality, and plant N, P, K content of peppers were determined. The interrelationship between the indicators was analyzed. 【Result】 The soil enzyme activities increased with the increase of irrigation amount. The soil urease, neutral phosphatase, sucrase, β-glucosidase and catalase activities of T4 were the highest, and the activities of some enzymes were not significantly different from those of T3.Compared with T1, the increases were 48.80%, 28.70%, 45.60%, 100.87% and 102.58%, respectively. With the increase of irrigation amount, pepper yield also increased, T4 increased by 29.05% compared with T1, and there was no significant difference in pepper yield between T3 and T4.The content of vitamin C and capsaicin in peppers decreased gradually with the increase of irrigation water, but the content of soluble sugar in peppers increased with the increase of irrigation water. The amount of irrigation increased the total accumulation of nutrients (N, P and K), the physiological use efficiency of N and K and the partial fertilizer productivity in pepper fruits and shoots. Except that the physiological utilization efficiency of P was lower than that of T4, the other nutrient utilization parameters of T3 were not significantly different from those of T4, and the physiological utilization efficiency of K was even significantly higher than that of T4.【Conclusion】When the irrigation amount is 4392-4733 t/hm² (T3 and T4), the soil enzyme activity, yield and nutrient utilization rate of pepper are all at high levels. The results of the study provide a theoretical and practical reference for the selection of the irrigation amount of facilities pepper in Sichuan Basin. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to explore the effects of chilling injury and pre-spraying of uniconazole ($3307) on the phys- iological metabolism of mung bean (Vigna radiata) leaves and yield, studying the effects of low temperature stress at the initial flowering stage on physiological and yield of mung bean, and the alleviating effect of pre-spraying $3307 on stress. [Method] The pot experiment in the research was conducted, and the crop cultivar included Lvfeng 5 (L5) and Lvfeng 2 (L2). S3307 was pre-sprayed and treated with con- tinuous low temperature (average 15 °C) for 5 days and samples were taken every day to analyze the cell membrane permeability, AsA-GSH cycle, content of osmotic adjustment substances in mung bean leaves and yield, and the mitigating effects of $3307. [Result] The content of malondialdehyde (MDA) and the electrolyte leakage in mung bean leaves were significantly increased by chilling damage at the initial flow- ering stage, and the content of ascorbic acid and glutathione, and the content of soluble sugar and soluble protein were significantly in- creased. The 100-seeds weight of L5 was significantly decreased by 2. 17% -16.60%, and the yield per plant was significantly decreased by 10. 37% -44.62%. At the same time, the 100-seeds weight of L2 was significantly decreased by 3. 33% -22. 14%, and the yield per plant was significantly decreased by 12.73% -45.69%. S3307 had the effect of resisting chilling damage at the initial flowering stage. Un- der low temperature conditions, pre-spraying $3307 effectively increased the soluble sugar and soluble content of mung bean leaves, significantly reduced the MDA content and the electrolyte leakage, and significantly increased the content of ascorbic acid and glutathione. Spra- ying $3307 had the regulatory effect of increasing the yield of mung bean. Under normal temperature conditions, L5 and 12 in a single plant significantly increased by 4. 70% and 7. 87%, respectively. Under the conditions of chilling, the 100-seeds weight was significantly in- creased by 1. 23% -3.32%, and the yield per plant was significantly increased by 3. 49% -8. 13% when 15 was treated for 1-5 days.. And 100-seeds weight was significantly increased by 1.72% -5.21%, and the yield per plant was significantly increased by 10.94% - 16.55% when 12 was treated for 1-5 days. [Conclusion] Low temperature at the initial flowering stage affected the physiological functions of mung bean leaves such as cell membrane permeability, AsA-GSH cycle, and osmotic regulation substances; Pre-spraying $3307 could ef- fectively alleviate the effects of chilling injury on mung bean physiology and yield. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to explore which proportion of nitrogen and phosphorus fertilizer combined with drip irrigation water and fertilizer integration in the Yellow River Diversion Irrigation Area can promote the accumulation and transfer of spring maize dry matter in Yinchuan Plain, and its effects on fertilizer utilization rate and yield, so as to provide a basis for the integration of drip irrigation water and fertilizer for spring maize in the Yellow River Diversion Irrigation Area. 【Method】The experiment was carried out in the Yinchuan Plain of the Yellow River Irrigation Area from 2019 to 2020. The maize variety Yinyu 274 was used as the material. The conventional application rates of local nitrogen and phosphorus fertilizers were 417 and 142.50 kg/hm². The conventional application rate of 70% nitrogen and phosphorus fertilizer was 291.90 and 99.75 kg/hm2. The conventional application rates of 130% nitrogen and phosphorus fertilizer were 542.10 and 185.25 kg/hm2. Six treatments with different proportions of nitrogen and phosphorus fertilizers were set up as T1 （N 0, P 0）, T2 （N 100%, P 70%）, T3 （N 100%, P 100%）, T4 （N 70%, P 100%）, T5 （N 130%, P100%）, T6 （N 100%, P 130%）. The effects of different ratios of nitrogen and phosphorus combined application on the dry matter accumulation, dry matter transport, grain contribution rate, nutrient utilization rate and yield of maize under drip irrigation, water and fertilizer integration were analyzed.【Result】The combined application of nitrogen fertilizer 291.9 kg/hm2 and phosphorus fertilizer 142.50 kg/hm² under the combined application of six kinds of nitrogen and phosphorus fertilizers had the best overall effect. The absorption of phosphorus and nitrogen by maize was significantly higher than that of other treatments. The nutrient requirements of maize throughout its growth period were satisfied. Compared with other treatments, the dry matter accumulation increased by 6.28%-22.90%, and the dry matter transport and grain contribution rate increased by 4.60%-11.10%. Compared with conventional combined application, nitrogen fertilizer utilization rate, phosphate fertilizer utilization rate, nitrogen fertilizer partial productivity and phosphate fertilizer partial productivity were significantly increased by 52.23%, 18.92%, 57.07% and 9.95% in T4 treatment. It can also significantly improve the corn ear formation rate, the number of grains per ear, and the weight of 100 kernels, thereby increasing the yield. The yield could be increased by 8.34%-9.95% compared with the conventional nitrogen and phosphorus application, and the maximum yield was 21 916.39 kg/hm².【Conclusion】The combined application of nitrogen fertilizer 291.90 kg/hm² and phosphorus fertilizer 142.50 kg/hm² under drip irrigation water and fertilizer integration in the Yellow River Diversion Irrigation Area can significantly increase the dry matter accumulation before and after flowering, and improve the dry matter transport, transport rate and contribution to seeds, and improve N fertilizer utilization, phosphorus fertilizer utilization and N fertilizer bias productivity, thus increasing maize yield. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to analyze the effects of sowing date and film mulching on yield and quality of direct seeding winter rapeseed to provide a theoretical basis for suitable sowing and high-yielding cultivation of winter rapeseed in dryland in southwest China. [Method] A two-factor completely randomized block design was adopted to explore the effect of sowing date(20th September, 30th September, 10th October, 20th October, 30th October, 10th November, 20th November) and film mulching (film mulching and no film mulching) on field soil temperature, dry matter accumulation, agronomic characteristics, yield and quality of Chuanyou 36. [Result] Film mulching effectively increased the 0-20 cm soil temperature, dry matter accumulation, plant height, length of main inflorscence and effective pods, thereby increasing rapeseed yield by 3.61%-44.47%, which was more obvious with the delay of sowing date. However, the sowing date delayed longer, dry matter accumulation and agronomic traits of rapeseed decreased significantly. The regression equation showed that the rapeseed yield rose first and then declined with the delay of sowing date, which had a significant polynomial relationship with sowing date. The optimal sowing date for rapeseed was 10th October, which was 2.13%, 47.97%, 74.19% and 136.64% higher than 30th September, 30th October, 10th November and 20th November, respectively. In addition, the delay of sowing date effectively reduced the content of linolenic acid, erucic acid and glucosinolates in rapeseed, but also reduced the oil content, while film mulching effectively decreased the difference in rapeseed quality resulted from the delay of sowing date. [Conclusion] 30th September to 10th October was a suitable sowing date for high yield of direct seeding rapeseed in dry land in southwest China, and a proper delay of the sowing period in combination with film mulching technology was more conducive to achieving goals of high yield, efficiency and quality. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to analyze the effects of pesticides fertilizer application on the occurrence of diseases and insect pests in sugarcane during inter-tillage period, and their production effects at jointing and maturity stages, so as to provide reference basis for scientific application of pesticide fertilizer in sugarcane.【Method】In this study, sugarcane cultivar Guiliu 05/136 planted in winter was taken as the research material. Referring to the production standard of sugarcane with high yield and high sugar in Guangxi, six different kinds of pesticides fertilizers with nutrient ratios and pesticides components were applied to sugarcane production during the inter-tillage period（from tillering stage to late tillering stage） as different treatments, and they were named as A,B,C,D,E and F,respectively. From May to October, the conditions of major plant diseases and insect pests in sugarcane seedlings under different treatments, and the growth rate of sugarcane plants at elongation stage were investigated. The yield traits were investigated at maturity, and the agricultural output value of sugarcane under different treatments were also analyzed.【Result】Application of pesticides fertilizer with N, P2O5, K2O≥30%（A,B,C,D and E treatments） promoted sugarcane tillering, appropriately applying with organic matter in which（B and D treatments） had better effect. At the same time, the smut and borer pest also got better control in sugarcane seedling. The pesticides fertilizer containing organic matter had a better indirect effect on smut, and which containing chlorantraniliprole and thiamethoxam could prevent and control borers in best. In addition, the application of pesticides fertilizers containing organic matter（B,D and F treatments） could not only promote the elongation of sugarcane stem in advance, but also promote rapidly growth for plants, and to form more millable canes, then increase their yield per unit area. Under the premise of the same cost of fertilizer, the agricultural increased of sugarcane treated with different fertilizer reached by 2118.62-9199.31 yuan/hm~2, among which D treatment had the highest value added.【Conclusion】The application of organic-inorganic compound pesticides fertilizer during the inter-tillage period have positive effect on the control of diseases and insect pests of sugarcane seedlings, and the control effect is closely related to the content of medicinal ingredients and nutrient ratio of fertilizer. The tillering of sugarcane can be effectively promoted by applying medicated fertilizer, which could also effectively improve the effect for sugarcane production, and two kinds of which the component of 35% N, P2O5, K2O content（17-7-11）,0.10% insecticide, 0.10% thiamethoxam, 3% organic matter or 30% N, P2O5, K2O content（13-6-11）,30 mL Durui, 0.10% thiamethoxam, 15% organic matter are more beneficial to increase sugarcane production efficiency, thus it is the best for sugarcane cultivation in Guangxi. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to explore the feasibility of reducing the amount of nitrogen fertilizer and a reasonable nitrogen reduction model under late sowing wheat in the Jianghan Plain. 【Method】 Field experiments were conducted with Zhengmai 9023 under traditional and late sowing date with three nitrogen treatments differing in ratios of basal to topdressing. The changes in wheat yield and its constituent factors and nitrogen related indicators were compared across treatments. 【Result】（i） Under the same nitrogen application rate and base-topdressing ratio, grain yield, panicle number and 1000-grain weight were significantly reduced delayed the sowing date. Reduced total dry matter accumulation during flowering and maturity under late sowing was due to the decrease in dry matter accumulation in leaves and stem sheaths; The dry matter accumulation in spike did not show significant change. The changes in dry matter accumulation at maturity were related to leaves, stem+sheaths and grain husk+spike axis. Under the same nitrogen application rate and base-topdressing ratio, the nitrogen accumulation in wheat at flowering and maturity decreased as well; Nitrogen accumulation in flowering leaves of increased under late sowing, but nitrogen accumulation in stem+leaf sheath, ripe leaves and ripe grain husk+spike axis decreased. Under the same nitrogen application rate and base-topdressing ratio, the spike formation rate and nitrogen use efficiency were significantly reduced under late sowing.（ii）Under different nitrogen fertilization treatments and the same sowing date, nitrogen fertilization can be reduced from 180 to 150 kg/hm² under late sowing with insignificant change in yield decreased by 3.33 kg/hm²（M1） and 293.34 kg/hm²（M2） in 2019—2020; 158.67 kg/hm²（M1） and 13.50 kg/hm²（M2） in 2020—2021. The reduction was much lower than that of normal sowing, and the reason was that the number of spikes and grain number per spike were stable when the nitrogen application rate was reduced from 180 to 150 kg/hm², and the 1000-grain weight increased to some extent. Further reducing the amount of nitrogen applied, the yield change under the two sowing dates did not reach a significant level. Under the same base-topdressing ratio, reducing nitrogen application rate, the nitrogen accumulation in the stem+leaf sheath and spike at the flowering stage and grain husk+spike axis were significantly reduced, but dry matter accumulation did not change significantly. Under the same sowing date and base-topdressing ratio, reducing nitrogen application rate, spike formation rate increased significantly, M1 nitrogen utilization efficiency increased significantly, and M2 nitrogen utilization efficiency remained stable. 【Conclusion】Under the conditions of continuous optimization of nitrogen fertilizer management mode, the yield of late sowing wheat under nitrogen reduction treatment was not significantly reduced compared with normal nitrogen yield, but the spike formation rate and nitrogen use efficiency were significantly improved. After a delay of 20 days, the recommended nitrogen fertilizer management model is that the ratio of base to topdressing is m（base fertilizer）∶ m（top dressing before winter）∶ m（top dressing at jointing stage）=1∶1∶1, and the nitrogen application rate can be reduced from the normal nitrogen application rate to 150 kg/hm². [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to the effects of phosphorus application rate on switchgrass growth and soil nutrients in saline-alkali soil, in order to determine the appropriate amount of phosphorus, which provided a theoretical basis for saline-alkali soil improvement and high yield and high efficiency cultivation of switchgrass in Yinbei area of Ningxia.【Method】In Yinbei area of Ningxia, switchgrass, an energy crop, was used as material to study the effects of different treatments on the growth, soil saline-alkali content and nutrient absorption and utilization of switchgrass by setting 0,30 and 90 kg/hm² of phosphorus fertilizer（expressed as P0, P30 and P90, respectively） through field experiments.【Result】At the mature stage of switchgrass, the soil salinity and alkali content in 0-100 cm soil layer of each treatment were all P0>P30>P90, and the soil organic matter, available phosphorus and alkali-hydrolyzable nitrogen contents were all P90>P30>P0. Compared with P0, P90 treatment significantly reduced the soil salinity and alkali content and increased the nutrient content. Phosphorus application contributes to the growth of switchgrass, which promoted the absorption and utilization of nitrogen and phosphorus, and improved the accumulation of aboveground dry matter. Under three phosphorus levels, soil nitrogen balance of payments were deficit, and soil phosphorus balance was surplus only under P90 treatment.【Conclusion】The comprehensive results showed that under the conditions of this experiment, 90 kg/hm² P application rate could not only ensure the good growth of switchgrass and obtain high biomass yield, but also alleviate the saline-alkali pressure, improve the soil nutrient status and maintain a reasonable balance of nitrogen and phosphorus. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to provide theoretical basis for rational application of nitrogen fertilizer to wheat, effects of reduced application rates of nitrogen on yield and quality of wheat were analyzed in Yunnan province. [Method] Using a two-factor randomized block design, the newly bred dryland wheat varieties Yunmai 76 and Yunmai 77 were used as materials to set up a nitrogen-use efficiency experiment including 5 N application rates, namely, 300 kg/hm²(N1),240 kg/hm²(N2), 180 kg/hm²(N3) and 120 kg/hm²(N4) and no nitrogen fertilizer(N5), respectively. The related indexes of grain yield, yield components and quality under different rates were determined. The correlation between grain yield and spike number, grain number per spike and 1000-grain weight was analyzed. [Result] Under different nitrogen application rates, the yield of Yunmai 76 and Yunmai 77 decreased with the decrease of nitrogen application rates. When the nitrogen application rate decreased from 300 kg/hm² to 240 kg/hm², the yield decreased by 1.38% and 0.30%, respectively; When the nitrogen application rate decreased to 180 kg/hm²or below 180 kg/hm², the yield was significantly decreased. In terms of yield components, the number of panicles per unit area significantly decreased with the decrease of nitrogen application rate; However, the effect of nitrogen application rate on 1000-grain weight and grain number per spike was not significant. The results of correlation analysis between yield and components showed that there was a extremely significant positive correlation between yield and panicle number(R=0.92）. There was no significant correlation with grain number per spike, but a significant negative correlation with 1000-grain weight. Under the rateof N180 kg/hm² and no nitrogen application, the yield of Yunmai 77 was 10.67% and 28.87% higher than that of Yunmai 76, respectively, and the yield decrease of Yunmai 77 was much lower than that of Yunmai 76 under the same N treatment. In terms of quality, protein content and wet gluten content decreased with the decrease of nitrogen application rates, and the differences were significant; The responses of sedimentation value, stability time and formation time to nitrogen application varied with different varieties. The sedimentation value of Yunmai 76 decreased at first and then increased with the decrease of nitrogen application rate, but the nitrogen reduction rate had no significant effect on the sedimentation value of Yunmai 77. [Conclusion] Yunmai 77 is a wheat variety with tolerant low nitrogen. Considering the yield and quality comprehensively, under the experimental conditions, when the conventional nitrogen application rate in this area is 300 kg/hm², the synergistic improvement of wheat yield and quality can be realized [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to analyze the effects of different chemicals (fertilizers) on the prevention and control of ratoon chlorosis as well as the influence of growth and yield in sugarcane to provide a reference for the high-efficient and low-cost control of ratoon chlorosis in sugarcane. [Method] Using a randomized block design, setting up 6 chemical treatments(fertilizers) in a first ratoon field in 2020, treatment A was spraying iron fertilizer on the leaf surface at 3-leaf stage seedlings, treatment B was 10. 0 kg/667 m² ferrous sulfate applied to the soil before emergence, treatment C was 20. 0 kg/667 m² of hydrated lime applied to the soil before emergence, treatment D was 500. 0 g/667 m² (diluted 3000 times) of soil irrigating and repairing bacteria in the root zone before emergence, treatment E was 1. 0 t/667 m² of biochar applied in the soil before emergence, treatment F was 1. 0 t/667 m² coal ash from the sugar mill before emergence, and no treatment was using as a control (CK). Seventy days after treatments, the incidence of chlorosis in the current year and the consequent ratoon year were counted, and agronomic characteristics such as plant height, tiller rate, number of leaves, and yield components such as millable stalks and stalk diameter were compared with the control, and were used in evaluation the control effects. [Result] The tested chemicals (fertilizers) had extremely significant (P < 0. 01, the same as below) control effects on sugarcane ratoon chlorosis, the range of control effect was 5. 57% to 71. 33% in year 2020, and 1. 96% to 73. 67% in year 2021. In 2020, treatment A (foliar spraying iron fertilizer) had the best control effect, with the 71. 3 3 % control effect, next was the treatment F (sugar factory coal ash) with 30. 01 % control effect. Treatment B and D had poor effect, and the difference was not significant (P > 0. 05), but both were significantly worse than other soil modulators (fertilizer) treatments. In 2021, the control effect of each soil modulator (fertilizer) treatment was extremely significantly different, and significantly (P < 0. 05, the same as below) or extremely significantly better than in 2020, especially the best treatment effect was F, reaching 90. 06%, followed by treatment E, and the control effect was 73. 67 %. All treatments can significantly promote plant growth, increase tillers, and leaves, in addition to extremely significantly improve the yield traits. Among them, treatment F performed the best effect. The cost of each treatment was in the range of 70 - 2100 yuan/667 m², and costs from high to low was E >A > F > C > D > B. [Conclusion] Foliar spraying with Fe2+ foliar fertilizer has a significant re-greening effect on sugarcane seedlings that have ratoon chlorosis, can quickly recover the yield loss caused by ratoon chlorosis, but the control time is short, and it is difficult to fundamentally prevent ratoon chlorosis of sugarcane. Considering the control effects, as well as cost and the influence of sugarcane growth, the applying coal ash 1. 0 t/667 m² is the best way to prevent and cure sugarcane ratoon chlorosis and sugarcane early growth and yield. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to analyze the main factors affecting the yield of Brassica napus L in different regions of Sichuan province, so as to provide theoretical basis for breeding B. napus L. varieties suitable for different rapeseed producing areas in Sichuan province. [Method] Variation analysis, correlation analysis and path analysis were used to analyze the relationship between the agronomic characters and the yield of B. napus L . [Result] In Xindu, Deyang and Dazhou regions, the most variation of agronomic trait was the first branch numbers. The value was the number of seeds per siliquain Chongzhou and Mianyang regions. It was the number of effective siliqua per plant in Nanchang, Yibin, Jianyang, and Leshan regions. The least variation of agronomic traits was the plant hight, in the Xindu, Chongzhou, Jianyang, Mianyang, and Deyang regions. It was 1000-seed weight, in the Nanchang, Yibin, Leshan, and Dazhou regions. The yield of Xindu region was significant or highly significant negative correlated with the first branch numbers and the number of effective siliqua per plant But, it was significant positive correlated with the plant hight and the number of seeds per siliqua. The yield of Nanchang region was significant or highly significant positive correlated with the plant hight, the first branch numbers, and the number of effective siliqua per plant. The yield of Yibin region was highly significant positive correlated with the plant hight. The yield of Jianyang region was significant or highly significant positive correlated with the number of effective siliqua per plant and the number of seeds per siliqua. But, it was highly significant negative correlated with the 1000-seed weight. The yield of Leshan region was significant positive correlated with the number of effective siliqua per plant. There was no significant correlation between yield and main agronomic traits in Mianyang, Deyang, and Dazhou region. In Xindu region, the greatest direct path coefficient and the greatest comprehensive effects were respectively the number of seeds per siliqua and the the number of effective siliqua per plant. Those were both the number of seeds per siliqua in Chongzhou region. In Nanchong and Jianyang regions, the greatest direct path coefficient and the greatest comprehensive effects were respectively the number of seeds per siliqua and the 1000-seed weight. Those values were respectively the number of effective siliqua per plant and the first branch numbers in both Mianyang and Dazhou regions. In Deyang region, the greatest direct path coefficient and the greatest comprehensive effects were both the number of effective siliqua per plant. [Conclusion] There were differences in the coefficient of variation of main agronomic traits of B. napus L in different producing areas of Sichuan province, and there were differences in correlation with yield. The effects of yield components on yield should be fully considered in breeding, as well as the comprehensive effects of other traits. The present study provides a scientific basis for breeding B. napus L varieties suitable for different regions of Sichuan province. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to improve the fruit quality, yield and water use efficiency of cherry tomato cultivated in solar greenhouse substrate. [Method] 'Jinfei' was used as the experimental material, and a completely randomized block design was adopted. Under the condition of split root irrigation, the total irrigation amount of cherry tomato in growth period was kept constant, the designed irrigation frequency was once a day (Dl), once every two days (D2) and once every three days (D3), the alternate frequency was that one side was irrigated once (Tl), twice (T2) and three times (TI), and then the other side was irrigated alternately, and a total of 9 treatments were used to analyze the effects of different irrigation frequency and alternate frequency on the quality, yield and water use efficiency of cherry tomato. [Result] The different irrigation frequency and alternate frequency had significant effects on the biomass accumulation of cherry tomato. The dry matter accumulation of DlTI was the highest, 249. 28 g/plant, but had no significant effect on the root shoot ratio;Reducing irrigation frequency could weaken the photosynthetic activity of plants and reduce the ability of leaves to capture light energy; The vitamin C content of D2 TI was the highest, which was significantly increased by 4. 49% to 191. 37 mg / kg compared with Dl Tl ; The contents of soluble solids and organic acids of Dl TI were not significantly different from those of D 1 Tl, but the contents of soluble sugar and sugar acid of Dl Tl were significantly increased by 20. 25% and 21. 33%, respectively;The average fruit weight, yield and water use efficiency of DlTI were significantly increased by 17. 76%, 9. 85% and 9. 85% compared with that of DlTl, respectively. [Conclusion]The comprehensive evaluation of treatment DlTI was the best, and it was the best irrigation strategy under alternate root zone irrigation. [ABSTRACT FROM AUTHOR]

[Objective] The present paper further explored the interaction between genotype and environment of different barley varieties, and provided theory and method for high quality cultivation of forage barley in different regions. [Method] The average value and significance level of yield traits of different varieties of forage barley at different altitudes were analyzed. The average value of yield traits in different regions were calculated and analyzed by multiple comparisons. The genetic variance, environmental variance and genetic environment interaction variance were estimated to compare the effects of heredity and environment on yield traits of feed barley. [Result] There were significant differences in effective panicle, number of filled grains, 1000 grain weight and yield among barley varieties; The results showed that the environment in Yuxi area was more conducive to the increase of effective panicles, the environment of Kunming area and Yuxi area was more conducive to the increase of the number of filled grains, the environment of Baoshan area and Dali area was more conducive to the increase of 1000 grain weight, and the environment of Yuxi area and Lincang area was more conducive to the increase of yield; The number of grains was mainly controlled by heredity, secondly by the interaction between gene and environment, and the influence of environment was the least. The effective panicle, 1000 grain weight, yield and other yield traits were greatly affected by environment, and the interaction variation between gene and environment was greater than that of heredity. [Conclusion] The yield traits were affected by heredity, so it was still the key to improve the yield of feed barley. According to the yield performance of different varieties in different regions, the key to improve feed barley yield in different ecological regions was to select high-yield forage barley varieties for promotion. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to explore the suitable straw returning methods for grain production in the Zitong River Basin. [Method] The impacts of straw non-returning (BR), straw mulching (FR), straw burying (MR) and straw heap back to field (DR) on soil fertility and grain production were investigated. [Result] Total nitrogen, available phosphorous and organic matter contents treated with FR, MR and DR increased by 18. 6 -38. 2 mg/kg, 5. 6 - 6 . 5 mg/kg, 0. 6 -2. 3 g/kg compared to BR treatment, respectively. The yield of rice, wheat, reap and corn increased by (1. 1 - 1. 3) x 10³, (0. 7 - 0. 8) x 10³, (0. 3 - 0. 5) x 10³, (0. 7 - 1. 0) x 10³ kg/hm², respectively. Returning straw to the field has significant effects on soil nutrients and grain yield. The contents of total nitrogen, available phosphorous and organic matter in DR treatment were significantly higher than FR and MR treatment, and the yield was slightly higher than FR and MR treatment. Rice, rape and corn all achieved the greatest economic benefits under DR treatment, with an average increase of 15. 6%, 27. 2%, 32. 1% compared with FR and MR, respectively. That of wheat on FR and FR was the same, 26. 7% higher than MR treatment. [Conclusion] Comprehensive analysis of the effect of soil fertility in the cultivated, grain yield and economic benefits, heap back to field is more conducive to the fertilization and grain production of the rice, rape and corn fields in the Zitong River Basin, and the straw mulching and heap back to field are both beneficial to the small grain production in the wheat field. [ABSTRACT FROM AUTHOR]

[Objective] This paper aimed to the problem that application of chemical fertilizers and pesticides and long-term continuous culti vation mode in the industry caused the yield and quality of Lycium barbarum L had declined in recent years, and the effects of different mi crobial agents on the growth and development of the L. barbarum L. and fruit yield and quality were studied. [Method] Ningqi No. 7 L. barba rum L. was used as experimental material, and the field trials with no microbial agents as a control were conducted by the application of Tl, T2, T3 three microbial agents. [ Result] Each treatment had different degrees of promoting effects on the vegetative growth, reproductive growth, yield and quality of L. barbarum L. plants. Microbial agents could significantly increase the survival rate of first-year L. barbarum L. seedlings, and the amount of roots and branch growth by 9. 06% - 57. 84% and 4. 76% - 54. 9%, respectively; Microbial agents could in crease the number of branches, branch growth and SPAD value of fourth-instar L. barbarum L. plants by 29. 9% - 87. 09%, 7. 5% - 18. 3%, and flower formation rate, fruit setting rate, 100-seed weight and yield by 2. 07% - 18. 87%, 3.19% - 13. 63%, 0.57% - 4. 92%, 29. 7% - 52. 7%, respectively; Especially, T2 had the most significant effect, compared with other treatments, the amount of branches, flower formation rate and yield were increased by 30. 05%, 12. 23% and 4. 45%. Microbial agents could significantly improve fruit quality and increase the content of polysaccharides, betaine, total flavonoids, and carotene in L. barbarum L. fruit by 4. 55% 25%, 25. 5% - 43. 67%, 12. 5% - 58%, and 2. 8 - 3. 6 times, respectively. Especially, Tl had the most significant effect on the improvement of quality indicators, compared with other treatments, the content of polysaccharides, betaine and carotene increased significantly by 5. 77%, 8. 52% and 23. 78%. [ Conclusion] Comprehensive evaluation of the analysis results showed that the three combinations of microbial agents tested had a certain positive effect on growth of L. barbarum L. . T2 had the most significant effect on tree growth, yield and economic benefits, Tl had the best effect on fruit quality, and it could be used for reference and promotion according to production needs in production practice, Tl and T2 could be used together to achieve the effect of improving quality and increasing production. [ABSTRACT FROM AUTHOR]

[ Objective] This paper aimed to compare the difference of yield and yield composition characteristics of different aromatic hybrid rice cultivars and screened the high-yield cultivars suitable for different nitrogen conditions. [Method] 8 aromatic hybrid rice cultivars and 3 non-aromatic cultivars were planted under three nitrogen application rates, including the low ( 0 kglhm2 ), medium ( 120 kg/hm2 ), and high nitrogen rate ( 210 kglhm2 ). At maturity, the grain yield and yield composition characteristics of each cultivar were measured and com pared, which was further analyzed by the correlation and path analyses. [Result] In most cases, the yield of aromatic rice cultivars was higher than that of non-aromatic control cultivars Gangyou 725 and II you 838, but lower than F you 498. Significant yield difference was observed among different rice cultivars, and the yield difference was mainly reflected under low nitrogen conditions or transfer from the medium to the high nitrogen conditions. Nitrogen application increased the panicle numbers per plant and spikelets per panicle, which in turn increased the total spikelets per plant and the panicle weight to increase the yield. The average yield increase of nitrogen application of aromatic varieties was smaller than that of non-aromatic varieties. Compared with non-aromatic cultivars, aromatic panicle rice had obvious advantages in panicle numbers and 1000-grain weight, however, the number of spikelets per panicle and panicle weight were lower than non-aromatic cultivars.The yield of aromatic cultivars was significantly positively correlated with the panicle numbers, the spikelets per panicle and the total spikelets per plant under the low nitrogen condi tions. Whereas, there was no significant correlation between the yield and yield components under medium and high nitrogen conditions, which could be caused by the exacerbated inhibilion between yield factors with nitrogen application increased. Path analysis showed that the total spikelets was the largest contributor to the yield of aromatic cultivars under different nitrogen conditions, followed by the panicle weight. The rice yield between different levels of nitro gen application showed a linear correlation, and the yield under medium and high nitrogen condition had the better correlation, while the low and medium condition was not so good. [Conclusion] Deyou 4727, Dexiang 146and Huaxiang 7 had more spikelets at low nitrogen condi tions, and coordinated yield components at medium and high nitrogen conditions, hence they could produce a high yield under all nitrogen conditions, which would be the optimal aromatic rice cultivars screened in this study. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to clarify the effect of different green manure in winter on the growth and yield of spring corn, and to provide the theoretical bass for the corn planting. 【Method】A study was conducted in Xundian county from 2018 to 2020, 5 green manure including Vicia sativa, V.villosa Roth var., Raphanus sativus, V.villosa, Lolium perenne were planted in the early autumn season and were returned to the field when the corn planting, and the winter fallow as control treatment. The plant height, stem diameter, leaf area per plant, the ground dry weight, ear length, ear diameter, grain number and hundred grain weight, bald tip length and yield traits were evaluated for the corn with different green manure treatments. 【Result】The results showed that the plant height, stem diameter and leaf area per plant increased by 4.74 %-27.01 %, stem diameter increased by 1.58 %-54.19 % and leaf area per plant increased by 1.53 %-178.25 %,compared with those in the control. The corn ear length, ear diameter, row grain number, hundred grain weight and ear grain number increased by 11.00 %-26.67 %, 3.75 %-37.92 %, 8.11 %-32.43 %, 14.84 %-22.58 % and 7.73 %-38.38 %, respectively. The length of maize barren tip decreased by 7.56 %-16.81 %.The yield of upper dry matter and mature stage increased by 10.43 %-279.88 % and 12.05 %-17.77 %, respectively. The effect of green manure returning to the field on maize yield increase was as follows, V.villosa Roth var.>Raphanus sativus × V.villosa Roth var.> V.villosa > Raphanus sativus > V.sativa > Lolium perenne > V.villosa Rothvar var.×Lolium perenne×Raphanus sativus > winter fallow, among them, Vicia villosa, Raphanus sativus×V.villosa Roth var. and V.villosa had the best effect on corn yield and increased over CK 17.77 %, 16.58 % and 16.25 % respectively. 【Conclusion】Therefore, in actual production, V.villosa, Raphanus sativus×V.villosa Roth var. and V.villosa could be selected as the green manure of spring corn before stubble. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to study the effects of three rice genes(OsGS3,OsGW2 and OsGN1 a) knockout on the field agronomic characters and quality of Jijing 809. 【Method】A randomized block test was used to compare the agronomic traits, quality and yield of the three gene knockout mutants with the wild type. 【Result】Compared with wild type, the tiller number and seed setting rate of mutants were significantly decreased, but the plant height, grain length, grain width and 1000 grain weight were significantly increased, and the yield was increased by more than 12 %. In addition, the change of brown rice rate was not significant, milled rice rate and head milled rice rate were significantly reduced, chalky grain rate and chalkiness degree were significantly increased, which affected the appearance and quality of milled rice. But amylose content, protein content and taste value did not change significantly. 【Conclusion】 The results suggested that three rice genes(OsGS3,OsGW2 and OsGN1 a) knockout could improve some characters and yield of rice, which provided practical evidence for the application of genome directed editing in breeding. [ABSTRACT FROM AUTHOR]

The present paper aimed to investigate the effects of seed dressing with different plant growth regulators on the growth, photosynthetic fluorescence characteristics and yield of corn seedlings, and to provide a theoretical basis for the application of chemical control technology in corn production. [Method] Taking Demeiya 1 and Zonda 101 as test varieties, the regulating effects on maize seedling morphogenesis, biomass accumulation, photosynthetic characteristics, chlorophyll fluorescence characteristics and yield of 4 regulators [Alginate oligosaccharide ( AOS ), 1-( 2, 4-dichloro Formylaminocyclopropanecarboxylic acid, B2 ), coronatine ( COR ) and anti-photolytic S-ABA ( ABA) J seed dressing treatment, seed dressing treatment without the addition of regulators to CK, were analyzed by a random field test. [Result] Compared with CK,AOS,B2,COR and ABA treatments all promoted the growth of Demeiya 1 and Zinda 101 seedlings,all of which could increase stem thickness and promote the accumulation of aboveground and underground biomass. AOS, B2 and ABA treatments increased the leaf area of the two varieties. Under COR and ABA treatments, the root-shoot ratio of Demeiya 1 was higher than that of CK. Under B2 and COR treatments, the root-to-shoot ratio of Zinda 101 was higher than that of CK. Under B2 and COR treatments, the chlorophyll content, P n, G,, T,, Y ( II), ETR and ( F,! Fm) of Demeiya 1 and Syndar 101 were higher than those of CK. Each treatment increased the number of spikelets and 1000-grain weight of the two varieties to different degrees. The yields of Demeiya 1 and Zonda 101 treated by AOS, B2, COR, and ABA increased by 4. 79 %,12. 38 %, 14. 79 %, 13. 38 %, and 13. 38 %, respectively, compared with CK. 6. 61 %,8. 40 %, 7. 35 %,4. 45 % . [Conclusion] The plant growth regulators, including AOS, B2, COR and ABA can promote seedling growth, improve leaf photosynthetic fluorescence performance, promote biomass accumulation, and increase maize yield. Among them, the effect of COR treatment on the output of Demeiya 1 was better, and the effect of B2 treatment on the output of Xunda 101 was better. [ABSTRACT FROM AUTHOR]

[Objective ] The objective of the paper is to provide the scientific basis for reducing chemical fertilizer and improving efficiency for vegetable in acidic yellow soil area of Guizhou. [ Method] The effects of combined application of biochar and yellow phosphorus slag on yield and nutrient uptake and utilization of Chinese cabbage cultivated in acidic yellow soil are studied by a pot experiment in green house. [ Result] The yield of Chinese cabbage under different treatments of biochar and yellow phosphorus slag combination is increased by 37.22 % - 82.07% compared with that of non-fertilization treatment, and the yield of Chinese cabbage applied with chemical fertilizer + 70 glpot biochar + 11.7 glpot yellow phosphorus slag is the highest ( 553. 5 g/ pot) . The nitrogen, phosphorus and potassium content in Chinese cabbage under different treatments of biochar and yellow phosphorus slag combination is increased by 39.9% - 57.9%, 1.31% - 35.22% and 1.99 % -39.09% respectively compared with that of non-fertilization treatment. The nitrogen, phosphorus and potassium uptake of Chinese cabbage under different treatments of biochar and yellow phosphorus slag combination is increased by 107.8% - 188.9%, 65.89% - 128.82% and 61.73 % - 122.97% separately. Except there is no obvious difference in phosphorus uptake of Chinese cabbage applied chemical fertilizer + 18.0 glpot yellow phosphorus slag and non-fertilization treatment, the nitrogen, phosphorus and potassium uptake of Chinese cabbage under other treatments of biochar and yellow phosphorus slag combination is higher than that of nonfertilization treatment significantly. Among various fertilization treatment, chemical + 70 glpot biochar + 11.7 g/pot yellow phosphorus slag has the highest nitrogen and phosphorus utilization efficiency, respectively 59. 01 % and 8. 83 %, while chemical fertilizer+ 100 glpot biochar + 9.00 glpot yellow phosphorus slag has the highest potassium utilization efficiency, which is 92. 10 % . [Conclusion ] Rationally combined application of biochar and yellow phosphorus slag can improve yield, nutrient uptake and utilization of Chinese cabbage, and low amount of biochar combined with high amount of yellow phosphorus slag has the best effect. [ABSTRACT FROM AUTHOR]

( Objective) The present paper aimed to solve at the deterioration of soil physical properties and decline of soil fertility by irrational fertilization in northern Liaoning province, and the effects of different fertilization treatments on soil physicochemical properties and spring maize yield in northern Liaoning province were studied. [Method] Successive 2 year field experiments were conducted in the main maize production area in the northern of Liaoning. Five different treatments with mixed chemical and organic fertilizers no nitrogen with chemical P and K ( CK),conventional fertilization( CK1), optimize fertilization(T1), organic manure combined with chemical fertilizer(T2), and humic acid combined with chemical fertilizer( T3) with three replications were examined. The soil bulk density, soil nutrients, maize yield and yield components of each treatment were compared. [Result] The humic acid and organic mature combined with chemical fertilizer could reduce soil bulk density, compared to conventional fertilization treatment, decreased soil bulk density by 2. 97 % and 3. 94 %, 1. 22 % and 3. 08 %, 2. 67 % and 3. 60 % in 5 -10, 10 - 15 and 15 - 20 cm of soil layers. Compared to conventional fertilization, applying humic acid and organic manure could significantly improve soil fertility, increased organic matter by 2. 38 % and 2. 98 %, alkali-hydrolyzed nitrogen by 5. 69 % and 9. 82 %,available phosphorus by 14.47 % and 19. 60 % and available potassium by 8.07 % and 7. 92 %. The maize yield of humic acid and organic manure treatment was higher than that of the conventional fertilization treatment, respectively, increased by 950 and 852 kg/hm 2 • (Conclusion ) The comprehensive analysis results showed that the measures of suitable fertilization in northern Liaoning province was that the amount of humic acid was 600 kg/hm² or organic mature was 1500 kg/hm² while the nitrogen application was 198. 9 kg/hm². [ABSTRACT FROM AUTHOR]

Abstract,[Objective] The present paper aimed to study the effects of accelerating germination days(D), gibberellin(GA), Brassinolide (BR) and their interaction on germination, emergence and yield of purple potato 'Heimeiren' in autumn cropping. [Method] In this experiment, the original seed of' Heimeiren' was used as experimental material, the split-split plot design with three factors were adopted to pregerminate the seed potato. [ Result] The results showed that there were significant effects of D, GA, BR and their interaction on germination rate, main stem number, bud number, bud diameter, bud length, emergence rate, main stem number per plant, stem number per hectare. The more germination days at 25 C before sowing, the bigger of bud number per tuber and stem number per plant with the higher yield. Compared with the treatment s without GA germination, bud number per tuber, main stem number per plant and yield of treatments with GA germination had been increased significantly. Compared with the treatments with BR500 germination, bud number per tuber, main stem number per plant and yield of treatments with BR100 germination had been increased significantly. Among all combinations, the bud number per tuber of treatment D2 + GA60 + BR100 was the highest while the main stem number per plant and fresh tuber yield of that were higher. [ Conclusion] The major factors that affect the contribution rate to yield was in the sequence of emergence rate, main stem number per plant, plant height and tuber number per plant. There was a unitary and hypo-two function relationship between yield and other index such as main stem number per plant, stem number per hectare and tuber number per plant while the theoretical optimal main stem number per plant was 2. 35. [ABSTRACT FROM AUTHOR]

[Objective] The effects of different nitrogen and potassium application amounts on NK nutrition utilization and yield of rapeseed on different soil types in rapeseed-tobacco rotation area was studied. The purpose of this paper was to provide theoretical basis and technical support for precision nutrient management and reducing chemical fertilizer of rapeseed production. [ Method] Field trials were carried out in 3 kinds of soil type to investigate yield and nutrition utilization of rapeseed with different nitrogen and potassium application amounts. Egression equations of the quadratic model between N and K application amounts and N and K nutrition utilization of rapeseed were established. The effects of different nitrogen and potassium application amounts on different soil types on yield of rapeseed was analyzed. [ Result] Yield of rapeseed with N 90 kg/hm² was the highest in red soil. Yield of rapeseed with N 180 kg/hm² was the highest in paddy soil. Yield of rapeseed with N 270 kg/hm² was the highest in sandy loam. The yield increasing effect of N was sandy loam > paddy soil > red soil. Contribution of N to yield was red soil > paddy soil > sandy loam. In red soil, nitrogen use efficiencies of rapeseed with N 90,180 and 270 kg/hm² was 63. 68 %,31. 53 % and 18. 59 % respectively. In paddy soil, nitrogen use efficiencies of rapeseed with N 90,180 and 270 kg/hm² was 54.95 %,42. 5 % and 29. 45 % respectively. In 8&l'ldy loam, nitrogen use efficiencies of rapeseed with N 90,180 and 270 kg/hm² was 31. 95 %,37. 14 % and 33. 29 % respectively. There was no significant difference in yield of rapeseed between treatment with K and no K. In paddy soil and in sandy loam, yields of rapeseed with K SO kg/hm² was higher than other treatments. The yield-increasing effect of K was red soil > paddy soil > sandy loam. Contribution of K to yield was red soil > paddy soil > sandy loam. In red soil, K use efficiencies of rapeseed with K 50, 100, 150 kg/hm² was 46. 52 %,30. 2 % and 28. 18 %, respectively. In paddy soil, K use efficiencies of rapeseed with K SO, 100, 150 kg/hm² was 38. 91 %,22. 89 % and 19. 61 %, respectively. In sandy loam, K use efficiencies of rapeseed with K 50, 100, 150 kg/hm² was 55. 6 %,31. 29 % and 18. 39 %, respectively. [ Conclusion] In red soil of Luoping City, application amount of N and K on rapeseed production should be reduced. In paddy soil of Chengjiang City, application amount of K on rapeseed production should be controlled. In sandy loam of Tengchong City, application amount of N on rapeseed production should be increased and application amount of K on rapeseed production should be controlled. It was important that different nutrient management strategy should be adopted on different soil types in different area. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to determine the appropriate soil water potential range for Crimson seedless grape after fruit setting and provide a theoretical basis for irrigation in production practice. [ Method] This research studied the effects of different soil water potentials on photosynthetic performance, fruit traits, yield and quality after fruit setting,3-year-old Crimson seedless grape was as test material.[Result] Increased soil water potential could promote the net photosynthetic rate (Pn) of leaves and delay the decline of the net photosynthetic rate with time, could increase the openness of leaf stomata and transpiration of water while the treads of stomatal conductance (Gs) and transpiration rate (Tr) were basically the same, could increase the water use efficiency (WUE) and slow down the decline of water use efficiency, in which the WUE of T1 ,T2 and T3 treatments increased first and then decreased and reached the highest at 40 days after fruit setting. Improved the soil water potential could increase the vertical and transverse diameter of the fruit, increase the single seed weight and single panicle weight, provide the single plant yield and the yield, in which the yield of T1 ,T2 and T3 treatment were higher 20.60% ,31.71 % and 43. 02 % than CK treatment, respectively, among them, the T3 treatment yield reached 150 450 kg/per hm2. It could decrease the dry weight and soluble solids of fruit with the increase soil water potential, in which the dry weight of fruit of T1 ,T2 and T3 treatment decreased by 3.85 % ,10.67 % and 14.09 % . The fruit hardness of T2 and T3 treatments decreased significantly. [Conclusion ] When the soil water potential keeps-40 - - 110 kpa, it can not only promote the photosynthesis of the leaves of Crimson seedless grape after fruit setting, improve the water use efficiency, but also stabilize the fruit yield and improve the fruit quality. [ABSTRACT FROM AUTHOR]

【Objective】 The present paper aimed to explore the nutrient utilization and yield characteristics of mechanical direct-sowing indica hybrid rice. 【Method】 Taken fifteen different indica hybrid rice cultivars as tested materials, the effects of mechanical direct-sowing under different N fertilizers levels on the absorption,translocation and utilization of N, phosphorus(P), potassium(K) and yield of indica hybrid rice during filling stage were studied, meanwhile the correlations of nutrient utilization characteristics with grain yield and N utilization efficiency(NUE) were explored. 【Result】 According to cluster analysis of yield, under mechanical direct-sowing, N fertilization treatment and three yield classification types had an obviously significant effect on the accumulation and translocation of N, P, K during filling stages and grain yield. There existed significantly positive correlations between the amounts of N, P and K translocation in leaves and stem-sheath under different yield types, which could promote nutrient translocation during filling stage and increase grain yield; However, the correlation coefficient of P and N, P and K significantly decreased in translocation conversion rate of P from heading to maturity stage, which could not significantly improve NUE. Under mechanical direct-sowing in different yield classification types, the various indicators on yield and nutrient utilization characteristics of N fertilization treatment were significantly higher than those of no N treatment. F you 498, Dexiang4103 and Chuanjiangyou 527 were high-yielding and high NUE indica hybrid rice cultivars, being the best cultivars in this paper referred as the mechanical direct-sowing condition. Compared with medium and low yield types, mechanical direct-seeding high-yielding cultivars promoted the accumulations of N, P and K at the heading and maturity stage, increased nutrient translocation in leaf and stem-sheath during filling stage, especially significantly enhanced the translocation amount of N and K in leaves and translocation amount of K in stem-sheath, further facilitated the translocation conversion rate of K in different vegetative organ, played the coupling effect of absorption and utilization of N and K and then promoted yield, which was the important characteristic of high-yielding indica hybrid rice under mechanical direct-seeding; The results also showed that on the premise of effective panicle number, high grain number per panicle and seed setting rate of high yield types, more than those of low yield cultivars, which was another important reason for high-yielding indica hybrid rice cultivars further to increase yield under mechanical direct-seeding. Correlation analysis indicated that there existed significantly positive correlations of the translocation amount of N and K in leaves and stem-sheath and the translocation conversion rate of K during filling stage with NUE, furthermore, the translocation amount and translocation conversion rate of K had high significant effects on grain yield and NUE under mechanical direct-seeding condition. 【Conclusion】 Compared hybrid indica rice varieties with the middle class and low-yield type, high-yielding varieties can significantly improve leaf nitrogen and potassium transfer volume, as well as the potassium transfer volume of the stem and then significantly improve the contribution rate of potassium transport in the strong period, which is significant for the production of hybrid indica rice and the utilization rate of nitrogen fertilizer in the coordinated increase of the live transmission, which is the main physiological characteristics of the high-yielding varieties of the hybrid indica rice. At the same time, under the premise of ensuring sufficient amount of effective ear( 200 × 104/hm2), higher per ear grain number( 173. 0 granule) and the yield rate( 89. 5 %) are another important characteristics of the high-yielding variety of hybrid indica rice. [ABSTRACT FROM AUTHOR]

【Objective (The present paper analyzed the effects of different planting densities and nitrogen application amounts on the yield，ap- pearance，quality and other economic characters of processed rice of Guiyu 8，in order to provide a theoretical basis for the scientific formula¬ tion of high yield，high efficiency and excellent cultivation techniques.【Method】 Four planting densities (2.4x105，2.7x105，3.0x105 and 3. 3 x 105clump/hm2，A1 - A4 treatments) and four nitrogen rates (120. 0，165.0，210.0 and 255.0 kg/hm2，B1 - B4 treatments) were designed，and field experiments were carried out with split plot design. Economical traits such as the yield of Guiyu 8 treated with dif¬ferent planting densities and different nitrogen application rates ， and the appearance and processing quality of rice were determined ， and the optimal planting density and nitrogen application amount of Guiyu 8 were screened.【Result】 Planting density had very significant effect on below). With the increase of planting density，there was no obvious change in the number of grains per ear，1000 grain weight and ear length of Guiyu 8，and the chalkiness and chalk¬iness rate increased gradually ， but there was no regular change in grain lengtli，grain wi(dth，lengtli wi(dth ratio and transparen¬cy. Witli the increase of nitrogen application，the highest seed¬ling number，1000 grain weight and yield increased first and then decreased，the number of effective panicles increased grad but tlie change rule of rice quality index was not obvious. The application of nitrogen fertilizer or the increase of planting density could significantly increase the yiel(J of rice, but when the fertilization was excessive or the density was high, the yiel(J decreased, and the grain length, length width ratio and transparency of rice quality index decreased. Both the planting density and the amount of nitrogen applied can affect the peak leaf area index. The peak leaf area index was closely related to yield. Being too high or too lowwould lead to a decline in yield. The results of interaction between planting density and nitrogen application showed that the yield of A3B2 was the highest,reaching 8. 33 x 103kg/hm2 ,followed by A3B3 intercropping! 8. 13 X 10* kg/hm2 ". However, the grain length, length-width ratio and transparency of A3B2 interaction were the lowest among all treatments,and the whole milled rice rate ranked the third,with poor comprehensive characters. Although the yield of A3 B3 was the second, the brown rice rate was the highest, the whole milled rice rate was the second, the grain width was the smallest,the length-width ratio was the highest,the transparency level was the highest,and the comprehensive characters were the best. 'Conclusion] Under the optimum planting density of 3.0 X 105 hole/hm2 !2 seedlings per hole) and nitrogen application rate of 210.0 kg hm2 (A3B3 combination) ,Guiyu 8 can obtain higher yiel(d of unhusked rice,ideal appearance and processing quality of rice. [ABSTRACT FROM AUTHOR]

[Objective】The present paper aimed to study the effects of different moisture treatments on soil water and salt changes and yield of mechanically harvested cotton during boll stage. ' Method (The experimental plot was used in the key laboratory test base of modem water¬saving irrigation corpus of Shihezi university and the water-saving irrigation test station of Shihezi university. Three water gradients were set up by pit test method, and each treatment was repeated three times. At the end of each growth period, the indexes of soil water content, soil salt content and yield were determined, and the effects of diferent water treatments on soil water and salt change and yield of mechanically har¬ vested cotton were analyzed. ' Result】 The results showed that in W2 (the lower limit of bud period was 60 ' , the lower limit of flowering and boiling period was 70 ' ), the water holding capacity of 0 - 60 cmsoil layer in the root layer of water treatment could reach 63. 28 ', which was suitable for crop growth. The range and the salt leaching effect were ideal, forming a desalting desalination zone, and the cotton field yield wa 5482.38 kghm2 , which wa 12.07 ' -30.39 ' higher than otlier treatments, and the water use efficiency wa 1.30 kgm3, which wa also the best. ' Conclusion 】The effects of different water treatments on the change of water and salt and cotton yield were significant, water treatment of W2 (lower limit of bud stage was 60 lower limit of flowering and boll stage was 70 ') was a more reasonable water control strategy [ABSTRACT FROM AUTHOR]

[Objective (The present paper aims to explore the effects of planting density on photosynthesis and yield of cucumber in the Si¬chuan Basin. ' Method】 Cucumber ‘ Chuanlv No. 11 ’ taken as material，five cultivation densities were set up. The chlorophyll content，leaf area，photosynthetic gas exchange parameters，chlorophyll fluorescence parameters and yield indicators of different leaf positions of cucumber in different density were determined. ' Result】 The effect of planting density on the photosynthetic apparatus of different parts of cucumber was also different. The lowering of net photosynthetic rate of cucumber plants from bottom to top was caused by non-stomatal factors，non- stomatal and stomatal factors，and stomatal factors. There might be a photosynthetic compensation mechanism; As the density of cucumber decreased，the yield per plant increased gradually，but the yield per 667m2 gradually decreased. ' Conclusion】 The study reveals the effects of different cultivation densities on different leaf positions of cucumber and provides a theoretical basis for the selection of cucumber planting density in spring in Sichuan basin. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to clear the effects of different biological agents on tomato growth. [Method] This study designed field split plot experiment and adopted biometrical method to research the effects of Bacillus subtilis agent(30 kg·hm-2), Trichoderma humatum agent(22.5 kg·hm-2), Yufeng ‘99’agent(30 kg·hm-2), Zhongnonglyukang agent(45 kg·hm-2) on tomato growth, yield, quality and soil physico-chemical properties in 2017-2018, and the application effects were compared and analyzed with the conventional chemical fertilizer(2179.5 kg·hm-2) simultaneously. [Result] There were obvious promotion effects on tomato growth, yield and quality when four biological agents applied. The tomato height increased by 10-26 cm and the stem diameter increased by 0.6-3.0 cm compared with the control. The fruit yield was increased significantly under different biological agents application, which was 1.22-1.53 times higher than that of the control and was 34.33 %-53.65% higher than that of the chemical fertilizer treatment.Besides, the incidence rate of umbilical rot and gray mold diseases of tomato were significantly reduced. The external and internal quality of tomato were improved in each agent application treatment, comparing with the chemical fertilizer treatment, the fruit color uniformity and maturity were increased significantly, and comparing with the control, the fruit Vc content increased by 14.40%-49.94 %, the sugar content increased by 8.68 %-37.85 %, and the titratable acidity reduced by 28.89%-56.76%.Meanwhile, these biological agents application through drip irrigation had significant effect on physico-chemical properties, compared with the chemical fertilizer treatment, the organic matter content increased by 30.43 %-83.48 %, and the soil pH and conductivity decreased slightly, which reduced the occurrence of soil salinization, and compared with the control treatment, the organic matter content increased by 66.67%-134.44 %, and the available nitrogen, phosphorus and potassium also increased significantly. These data showed that the four biological agents could improve soil fertility. [Conclusion] This stuly indicated that the four biological agents could promote tomato growth, reduce diseases and improve yield and quality, the order of the promotion effects was as follows:yufeng‘99’agent> Zhongnonglyukang agent> Bacillus subtilis agent> Trichoderma humatum agent, which was closely related to component and mechanism of different biological agents and the effects of agents on soil microenvironment. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to analyze the effect of water regulation on the growth and development of rice and irrigation water use efficiency. 【Method】Three water gradients were set at tillering stage to control water content. At the end of each growth period, the indexes were sampled and measured. 【Result】Water regulation at tillering stage had significant effect on rice growth and irrigation water use efficiency under two cultivation methods. W1 and W2 treatments had little effect on rice plant height, and W3 treatment reduced plant height seriously under water stress. Water regulation at tillering stage has obvious influence on the final tiller number, which shows that the average number of tillers under mulching cultivation is 17.44 per hole, and the average number of tillers under bare land cultivation is 17.60 per hole. W2 treatment can maintain a higher leaf area at the later growth stage, which is more conducive to the accumulation of photosynthetic products and the formation of final yield of rice. Under the condition of film mulching and bare land cultivation, the utilization rate of irrigation water of W2 treatment was the highest, which was 0.64 and 0.46 kg/m~3 respectively. 【Conclusion】Appropriate water stress at tillering stage of drip irrigation rice is beneficial to rice growth and development and then to increase yield. From the perspective of drip irrigation rice to improve irrigation water use efficiency and yield, W2 water treatment of drip irrigation rice film mulching cultivation mode can be used as a more appropriate control measure based on the experimental conditions. [ABSTRACT FROM AUTHOR]

【Objective】The present paper aimed to explore the application effect of ’gather soil ridging + narrow strains with broad-rows’ cultivation mode in Sichuan Basin, and provide scientific guidance and theoretical basis for peach ochard establishment in Sichuan Basin and southern shallow hills in the future. 【Method】This study compared the effects of different cultivation modes on the growth, yield, quality and economic benefits of peach cultivars ’Xiahui No.6’. 【Result】The results showed that the diameter of trunks, main branches, lateral branchs, length of regenerated branches, number of roots less than 0.50 cm, chlorophyll content of leaves, fruit soluble solids and total sugar content and solid acid ratio, yield per plant for ’gather soil ridging + narrow strains with broad-rows’ were markedly higher than for the control group after planting 39 months; However, there was no significant difference in the appearance quality and output value of peach fruit per unit area under two different cultivation modes. 【Conclusion】’Gather soil ridging + narrow strains with broad-rows’ and combined with tree pruning can effectively extend canopy, improve plant light conditions, enhance the peach plant growth, improve the quality of the fruit flavor, which is a practical and efficient cultivation mode for southern peach orchard. [ABSTRACT FROM AUTHOR]

[Objective] This paper aims to provide optimal fertilization guidance for high-yield cultivation of P. frutescens and promotion of new P. frutescens varieties. [ Method] The effects of nitrogen, phosphorus and potassium fertilizers on the yield of two new P. frutescens varieties ( Qisu 2 and Qisu 3) were studied by ternary quadratic orthogonal rotation design. The regression equation and model analysis were constructed to optimize the high-yield fertilization mode. [ Result] N was the most important factor influencing the yield of P. frutescens. However, the two varieties varied in response to P and K fertilization. The regression models of nitrogen (x1) , phosphorus (x2) and potassium (x3) of the yield (Y) are Y = 2219.384 + 405.410x1, +304.926x2 - 156.723x12 -78.676x22 - 214. 479x1x2, and Y =2048.806 + 319.535x1, +54.722x3 -63. 102x12 - 113. 664x22 +76.017x32 -69.069x1x2, respectively. The best fertilization ratio of N, P and K fertilizer was (286.022 ±25.288),(139.059 ±20. 819),(180. 000 ± 35. 860) kg/hm2 , and (338. 180 ± 16.617) , (80. 923 ±21.314) , (203.529 ± 24. 278 ) kg/hm2, respectively. The yield of P. frutescens could reach 2250 kg/hm2. [ Conclusion ] Compound application of NPK fertilizers functioned significantly in enhancing P. frutescens yield. [ABSTRACT FROM AUTHOR]

[Objective] The aim of this paper was to provide a theoretical relerence for the application of loss-control urea in rice production in yellow soil. [Method] Based on the same application rates of phosphorus and potassium fertilizer, the rice cultivar Leyou 58 was employed to explore the ellects of loss-control urea, with various adding amount of loss-control agent (1 %,2%,3%,4%,5%,6%), on rice yield, nutrients uptake and utilization. Meanwhile, no nitrogen and common urea fertilizer were taken as the controls. [Result] No regular changes of rice yield observed with increasing the dosage of loss-control agent, while the accumulation of nitrogen in rice grain, nitrogen, phosphorus and potassium in rice straw, and potassium in aboveground parts showed regular variation. At the same time, regular changes were also observed on rice nitrogen, phosphorus, potassium harvest index and potassium absorption efficiency. Compared with common urea treatment, six kinds of loss-control urea with the loss-control agent of 1 % -6 % could increase the rice yield in some degree, among which 1 % adding amount performed the best. The yield increasing rate was up to 12.22 %. The adding amounts of 1 % , 2 % and 6 % enables absorption of nitrogen, phosphorus, potassium by rice and accumulation in the rice seeds sufficiently to promote the yield and quality of rice. The adding amount of 3 % enhanced the accumulation of nitrogen, phosphorus and potassium in rice straw, increased the resistance and promoted the growth. [Conclusion] To sum up, the effect of urea with 1 % loss-control agent performed the best in rice production. [ABSTRACT FROM AUTHOR]

[Objective]The present paper aimed to ensure the water-saving effect of super absorbent polymers on mango cultivation, and guide the water-saving cultivation of mango. [Method]A field experiment was set up to compare the effect of 40 %, 60 %, 80 %, 100 % conventional irrigation quantity co-applied with super absorbent polymers(40P, 60P, 80P, 100P, respectively) on soil water content, fruit quality and yield of mango orchards, with conventional irrigation quantity as the control(CK). [Result] The results showed that 40P treatment significantly reduced the soil water content, fruit quality and yied, wihle improved fruit weight(P <0. 05). The treatments of 60P, 80P and 100P significantly increased the soil water content, whose fruit weight and yied were not significantly different from the control. 80P and 100P treatments could significantly improve the internal quality of fruits, while except for the soluble solid content of 60P treatment evidently higher than the control, no significant differences of 60P and CK in fruit internal quality were observed. The correlation analysis showed that there was a very significantly positive correlation between soluble sugar content and the contents ofβ-carotene and carotenoid(P <0. 01). According to the weight analysis result, sugar-acid ratio, solid-acid ratio and carotenoid content were important indicators for evaluating the comprehensive performance of mango fruit quality and yield. The principal components analysis demonstrated that the comprehensive performance of fruit quality and yield of 60P, 80P and 100P treatments was better than the control, that was, 40% of water could be saved by applying super absorbent polymers, while 80P treatment had the best comprehensive performance. [Conclusion]To summarize, in the actual production, 80 g super absorbent polymers can be applied to each mango tree, and irrigation volume can be appropriately reduced to obtain the best mango fruit quality and yield. [ABSTRACT FROM AUTHOR]

[Objective] The purpose of this paper is to provide theoretical basis for efficient fertilization of pepper in yellow soil region of Guizhou province. [Method] Field test method was used to test the application of three slow-release fertilizers(stable fertilizer, nitro dualeffect fertilizer and controlled-release fertilizer) on pepper in the typical yellow soil area of Guizhou province, and to study their effects on yield, quality, nutrient absorption and fertilizer utilization of pepper. [Result]The yield of pepper increased by 14. 3 %-19. 4 % after applying three slow-release fertilizers, which was significantly higher than that of conventional fertilization and no fertilization. The amino acid content of pepper was 8. 9 %-22. 7 % higher than that of conventional fertilizer, and the crude protein content was 2. 4 %-10 % higher. The nutrient contents of pepper leaves, stems and fruits were improved as well as the agronomic efficiency, partial nitrogen productivity and apparent nitrogen utilization rate of pepper. [Conclusion] The application of three slow-release fertilizers significantly increased the yield of pepper, improved the quality of pepper and increased the fertilizer utilization rate of pepper. [ABSTRACT FROM AUTHOR]

[Objective] The purpose of this paper is to improve the yield and quality of Chinese bayberry and promote the development of green-efficient bayberry industry. [Method] Taking Biqi bayberry as test materials, the application of humic acid soluble fertilizer(HASF)was studied for higher yield and better quality fruit, while two field experiments were conducted in Fumin County and Panlong District, Yunnan Province. [Result] The results showed that the yield and fruit quality were improved by spraying HASF with 800-1000 times concentration at pre-flowering, young fruit and fruit enlarged stage, based on conventional fertilization. The average single fruit weight, yield and net income of bayberry of spraying HASF were significantly higher than those of spraying water(CK), with up to 27. 86 %-31. 54 %, 13. 0 %-13. 4 % and 13. 8 %-14. 2 %, respectively, and the contents of soluble solids and vitamin C(Vc) increased by 18. 4 %-19. 54 %and 18. 56 %-24. 9 %, respectively. However, compared with conventional fertilization, spraying water had no significant effect on fruit yield and quality. [Conclusion] The yield, quality and economic benefit of bayberry could be improved significantly by applying HASF. [ABSTRACT FROM AUTHOR]

【Objective】 This paper aimed to study the mechanism of the effect of high temperature during tuber formation on potato starch formation.【Method】 The test was designed using a single factor randomized block design with 3 treatments[ room temperature treatment(T1):(25±2)°C, local natural temperature(T2):(29 ±2)°C, and high temperature treatment(T3):(35 ±2)°C. In the potato tuber formation stage, the total starch, amylopectin and amylose content of tubers, ADPG-PPase, GBSSase, SSSase and SBEase activity, as well as yield and composition factors, were determined in the early, middle and late stages of potato tuber formation, tuber expansion, major starch accumulation and ripening harvest. 【Result】Compared with T1 treatment, T3 reduced total starch content, linear and amylopectin content by 33.70 %, 7.85 % and 35.88 %, respectively; T3 treatment of starch formation key enzymes ADPG-PPase, GBSSase, SSSase, SBEase activity than that of T1 decreased by 32.24 %, 27.90 %, 16.11 % and 42.74 %, respectively; Through path analysis, the effects of key enzymes of potato starch formation on starch formation in different growth stages were different.(i) High temperature was not conducive to the formation of potato tuber starch;(ii) High temperature during tuber formation reduced the activity of potato starch forming enzymes ADPG-PPase, GBSSase, SSSase and SBEase;(iii) The effect of high temperature on tuber production during the tuber formation period reached a significant level, reducing its economic benefits. 【Conclusion】The low temperature during potato tuber formation was conducive to the formation of potato tubers and the accumulation of starch in the later stage, which would provide a theoretical basis for the high-yield and high-efficiency cultivation and breeding of potato in the rain-fed areas of southern Ningxia. [ABSTRACT FROM AUTHOR]

[Objective] This paper aimed to seek the effect of different planting patterns, densities and the remaining fruit clusters on the growth, yield and quality of tomato. [Method] Taking ‘Fenyan I’ tomato as tested material, the experiments were designed with twelve treatments, including two pattern levels (2 rows for A1 planting; 1 rows for A2 planting), three density levels ( B1 planting density of 30 B2 plants per hm2; B2 planting density of 40 500 plants per hm2 ; B3 planting density of 54 B3 plants per hm2 ;)and two remaining fruit clusters (K1 with 3 fruit clusters; K2 with 4 fruit clusters). [Result] With the increasing of density and fruit cluster levels, the amplification of plant height was quick trend, the changes of plant stem diameter and leaf area were slow trend, the content of chlorophyll increased significantly, and the leaf stomatal conductance, transpiration rate and photosynthetic all increased then fall. The fruit shape index displayed no significant difference in tomato fruit, however, under the same planting pattern and density, the soluble sugar, organic acids, soluble solids, Vc, and sugar-acid ratio showed different trends with the increase in the remaining fruit clusters. The parameters such as chromaticity angle and color ratio in the luster parameters can reflect the change of color during the development of tomato fruit. Under the same planting pattern, the effects of different planting densities and the remaining fruit cluster on tomato yield, the average weight of single fruit and average yield of plot were all significantly different. [Conclusion] When the suitable production pattern and density for remaining fruit cluster in greenhouse was (2 rows for A1 planting; B2 planting density of 40 500 plants per hm2 ; K2 with 4 fruit clusters), the yield was the highest and 95047.2 kg/hm2. [ABSTRACT FROM AUTHOR]

[Objectives]The purpose of this paper is to explore the effect of water retention agent (SAP) on potato growth in high altitude area of Guizhou, and to provide references for high-yielding cultivation of potatoes and efficient application of water and fertilizer in Guizhou. [ Methods] A field experiment including water retention agent dosage is done. This research takes the ‘ Taro 5 ’ as the experimental material, five water retention agent dosages(0, 37.5, 52.5, 67.5, and 82.5 kg/hm2 ) is arranged to study the effect of SPA on the yield, potato character, nutrient quality and soil fertility of potato, to determine the appropriate amount of water retention agent in this area. [ Results] The results showed that the potato seedling rate after applying the water retention agent was up to 93. 37 % , the yield increased by 7.96 % - 13. 37 % compared with T1 treatment, and the yield of single plant was 6.81 % -45.45 % , and the yield of single plant increased by 34. 92 % -83.31 %. Application of super absorbent polymers could significantly improve the potato starch content by 2.49 -5.35 percentage compared with T1 treatment, but the nitrogen, phosphorus, potassium, moisture content and reducing sugar content had no obvious effect. In terms of soil nutrient changes, the contents of soil organic matter, total nitrogen, total phosphorus, available phosphorus and available potassium were increased by 4. 61 % -27.01 % , 0 -19.01 % , 7.83 % - 15. 65 % , 5. 73 % -22.49 % and 5.08 % -25.42 % respectively compared with T1 treatment. [ Conclusions] The recommended application of water-retaining agent 52.5 -82.5 kg/hm2 was beneficial to high yield and soil fertility of potato in the high altitude area of Guizhou. [ABSTRACT FROM AUTHOR]

[Objective]This paper studied the influence of different treatments on the growth, yield and quality of new shoots of the tea tree, and provided the theoretical basis for the pruning of adult tea tree in Yunnan Province. [Method] Using Yunnan big-leaf tea varieties 4 Fox-iang 1-11' as the material to do the field experiment, setting two different period treatments with light pruning in winter and spring after spring tea, and the picking period, mechanical composition, fresh leaf yield, water extract, tea polyphenols, amino acids, caffeine and other physiological indexes of tea shoots were compared and analyzed. [Result] The period to pick spring tea and summer tea with light pruning in winter were 11 and 8 days eariier than that with light pruning after spring tea, but the spring tea picking period was shorter than that of light pruning after spring tea. The yield of light pruning after spring tea was 11.26 % higher than that of light pruning in winter, and the difference was significant between the two treatments. Light pruning treatment after spring tea could improve the quality of fresh tea bud, and its normal bud leaf proportion was 100% , which with winter light pruning was at 73.4 %. The nonnal fresh tea bud proportion with light pruning treatment after spring tea was significantly higher than that with winter light pruning treatment. The content of polyphenols and caffeine of tea were significantly increased after pruning. Pruning after spring tea could improve the aroma and taste of spring baked green tea and sun-dried green tea, and the white fuzz of the dry tea was obvious. [Conclusion] The above showed that the light pruning after spring tea could improve the yield of fresh leaves and the quality of spring tea, and the growth of white fuzz form resistance structure, and was an agronomic; measure to increase the yield of Yunnan big-leaf varieties. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to discuss the effects of different selenium fertilizer concentration on waxy maize yield, selenium content and heavy metals content, to provide scientific references for applying selenium fertilizer of waxy maize. [Method] Taking different types of waxy maize (GTN611, GN615 and GHN609) as materials, by spraying different concentrations of water soluble selenium fertilizer (0.0, 0.5, 1.0, 1.5,2.0 g/L) in maize big trumpet period, to analyze the effects of selenium fertilizer on waxy maize yield, selenium content and heavy metals content. [Result] Spraying different concentration of selenium fertilizer was not significant to waxy maize yield and yield related traits. With the increase of selenium fertilizer concentration, different types of waxy maize varieties grain selenium content increased, the largest rise was GN615, that selenium content up to 0.265 mg/kg and 2.82 times than the contrast. Waxy maize varieties of cadmium and arsenic content were decreased with the increase of concentration of selenium fertilizer, the cadmium and arsenic content reduction of the GTN 61 1 were most distinct, the biggest drop was 52.94% and 77.78%, respectively. The correlations between waxy maize selenium and cadmium, arsenic were -0.5509 and -0.8530, reached significant and extremely significant negative correlation respectively. [Conclusion] Spraying exogenous selenium fertilizer had no obvious increase on waxy maize yield, but increasing concentration of exogenous selenium fertilizer could significantly increase the selenium content of different varieties of waxy maize grain, and reduce the content of cadmium, arsenic in the meantime. [ABSTRACT FROM AUTHOR]

[Objective] Biopesticides application through drip irrigation systems is an important green pathway to prevent diseases in Xinjiang cotton fields, especially soil-spread diseases. The present paper was conducted to clear the suitable dosage of different biological agents to control cotton Verticillium wilt. [Method]The field split plot experiment was designed to research the effects of Bacillus suhtilis agent (15, 30 and 45 kg.hm-2), Trichoderma hunuitum agent (15, 18 and 24 kg.hm-2), Yufeng ‘99' agent (15, 22. 5 and 30 kg.hm-2), Zhongnonglvkang agent (30, 45 and 60 kg.hm-2) and horseradish agent (45, 60 and 75 kg.hm-2) on the prevention of cotton Vertilli-um will during 2016 and 2017.The control effect of Verticillium wilt, cotton growth, cotton yield and fiber quality were compared and analyzed by biometrical method. [Result]The five biological agents application could significantly reduce incidence and disease index of the cotton Verticillium will, and the average control effect reached 33.50% -74.94% . When the application amount of Trichoderma hunuitum a-genl was 18 kg.hm-2, the control effect was significantly higher than 15 anc I 24 kg.hm-2. There was no significant difference between different application amounts in horseradish agent treatment. The control effect had significantly positive correlation with application amount in other three agents treatments. There were obvious promotion effects on cotton growth when five biological agents were applied. The cotton height, width of inverse fourth leaf, branch number and boll number were increased in different levels under different agents application. The cotton height and width of inverse fourth leaf had no obvious changes and the number of branch and boll were increased with the application amount increasing. Meanwhile, these biological agents could significantly advance the maturity of cotton. The cotton seed yield showed an increasing trend and was increased significantly with the application amount except horseradish agent. The cotton fiber length and fiber breaking tenacity were improved slightly but the improvement effect was not significant in each agent application treatment. [Conclusion] Therefore, according to cotton disease control effect, cotton growth and yield performance, the proper application amount was suggested to be 30 kg.hm-2(Yufeng‘99'agent), 60 kg.hm-2 (Zhongnongl vkang agent), 45 kg.hm-2 (Bacillus subtilis agent) and 18 kg.hm-2 (Trichoderma humatum agent), and the dosage of horseradish agent needs to be further studied. [ABSTRACT FROM AUTHOR]

[Objective] This paper aimed to select the optimal nutritious liquid for cucumber cultivation in greenhouse. [Method] Cucumber Boma 626' was used as tested materials, and random single factor was adopted in the test. Compared with the contrast group, the experiment three nutritious solution formula (including nutritious liquid for garden test, and Shanqi and Shandong liquid) was designed, the different concentration gradients (one second of nutritious liquid was used during seedling period, two thirds of nutritious liquid was used during flowering period and standard nutritious liquid was used during fruiting period) was used, and the effects of different nutritious solution liquid on the growth, fruit quality, output and water use efficiency of cucumber were studied. [Result] All the different formula nutritious solution could promote the growth of cucumber, improve fruit (]uality and increase the yield of cue umbo-. Of which the study group using garden test standard indicated the obvious changes compared with contrast group, its plants was 13.99 % higher than that of contrast group; Root vigor increases 4. 95 % - 36. 19 % ; The effective photosynthetic leaf area and chlorophyll content increased and Pn by 12. 55 % -22. 09 % compared with the target yield (CK). This treatment was beneficial to the accumulation of sugar in fruit, significantly reduces the nitrate content by 11.33 % and increased the yield of 11.77 % , reducing total fertilization 30. 65 % , improving soil microbial environment, increasing the number of bacteria 23. 43 % , increasing the catalase and urease activity of 46. 33 % , 68.06 % , promoting available nutrient content, increasing the available phosphorus by 31.99 % , and water productivity was 108. 24. [Conclusion] The nutritious solution for garden test shows the best effect, which not only can promote the growth of cucuml)er nutrition but also help to improve fruit yield and quality, the solution is recommended to be widely used. [ABSTRACT FROM AUTHOR]

【Objective】This paper aimed to investigate the effects of biochar on cotton yield and phosphorus use efficiency in different raw materials. 【Method】Four treatments[control(CK), cotton straw biochar(BC1), corn cob biochar(BC2) and chicken manure biochar(BC3) ]were designed, and each treatment had two levels of phosphorus(P2 O5) : 0, 175 kg·hm-2, expressed in P0 and P1. The effects of different biochar on cotton yield and phosphorus use efficiency were studied. 【Result】Compared with the control, three kinds of biochar application could improve soil total phosphorus content. Under the level of P0, BC1, BC2 and BC3 respectively compared with CK increased by 3.3 %, 5.6 %, 8.9 %, and the level of P1, CK were increased by 7.9 %, 8.9 %, 11.7 %. The application of three biochar could increase dry matter weight and yield of cotton. Under the condition of no phosphorus, the yield of cotton treated with BC1, BC2 and BC3, compared with CK, increased by 3. 7 %, 7. 5 % and 11.4 %, respectively. Under P1 conditions, the cotton yield compared with CK increased by 17 %, 16 % and 20 %, respectively. BC1, BC2 and BC3 could significantly increase apparent utilization rate of phosphate fertilizer, which respectively increased by 28 %, 167 % and 202 %, compared with CK. 【Conclusion】The application of biochar from different raw materials could significantly increase cotton yield and phosphorus utilization, among which the biocarbon from chicken manure was the most important. [ABSTRACT FROM AUTHOR]

【Objective】This paper aimed to provide a theoretical basis for rational planting of tobacco in Guizhou yellow soil. 【Method】A field experiment was conducted with two plant patterns of rotation and continuous cropping in Zunyi city in the year of 2016 and 2017, and total amount of nitrogen, phosphorus and potassium were consistent within a rotation period. Root morphology, yield and nutrient utilization of rotation and continuous were determined and soil nutrition was analyzed after flue-cured tobacco harvested. 【Result】Compared with continuous cropping of tobacco, root length, total surface area, total volume was obviously increased by 5601.1 cm, 1976.3 cm2 and 59.17 cm3 under rotation cropping of rice and tobacco, the average diamond was decreased by 0.17 cm. The yield and output of tobacco of the continuous pattern were 1098 kg·hm-2 and 28 548 yuan·hm-22, respectively, lower than that under the rotation cropping pattern. The absorption of N and K under rotation cropping were higher than continuous cropping. Soil pH at 0-20 and 20-40 cm were decreased after crop harvested, and the soil alkali hydrolyzable nitrogen, available phosphorus, available potassium, nitrate nitrogen and ammonium nitrogen were increased in continuous cropping of tobacco. 【Conclusion】The nutrients uptake, yield and economic benefits of tobacco under rotation of rice and tobacco were better than continuous cropping of tobacco, so we should pay attention to the rotation of tobacco and rice or other crops to increase yield and output, thus to promote sustainable development of tobacco industry. [ABSTRACT FROM AUTHOR]

【Objective】This paper aimed to study the characteristics of nitrate nitrogen accumulation in tropical soil and its relationship with pH and chilli yield under different fertilization treatments. 【Method】‘Hunan Chilli 17 ’was taken as experimental materials. Chilli was subjected to seven fertilizer treatments[no fertilizer( CK),single application of chemical fertilizer( CF),chemical fertilizer plus straw application( CFS),chemical fertilizer plus organic fertilizer( CO),75 % of chemical fertilizer plus organic fertilizer( TCO),50 % of chemical fertilizer plus organic fertilizer( HCO),single application of organic fertilizer( OF) ]. 【Result】The amount of nitrate nitrogen and its accumulation amount in soil profile could be improved by applying organic fertilizer,chemical fertilizer or organic and chemical fertilizer combined application and increased with fertilizer application rates; There was extremely significant effect of different fertilization treatments on nitrate nitrogen accumulation amount in soil profile from 0 to 100 cm( P < 0. 01). With the same fertilization level of chemical fertilizer,the amount of nitrate nitrogen accumulation could be reduced by applying organic fertilizer or straw. Different fertilizer treatments had different effects on the transfer ability of nitrate nitrogen in tropical soil,the application of chemical fertilizer could accelerate nitrate nitrogen to the deep soil leaching,while the rational application of organic fertilizer and straw could slow nitrate nitrogen to the deep soil leaching. Besides,in 0-20,0-40,0-60,0-80,0-100 cm soil profiles,the amount of nitrate nitrogen accumulation had a extremely significant positive relationship with chilli yield( r > 0. 6961,P< 0. 01),and the amount of nitrate nitrogen accumulation in soil had an important effect on chilli yield. 【Conclusion】The rational application of organic fertilizer and straw could reduce nitrate accumulation and leach migration in the soil. [ABSTRACT FROM AUTHOR]

【Objective】The present paper was conducted to explore the effect of the mixture compound of thidiazuron and ethephon on dehydration effects, yield and quality of spring maize.【Method】The Xianyu 335 and Xinxin 2 were treated with thidiazuron and the mixture compound of thidiazuron and ethephon at dough stage, with water as control. 【Result】Compared to the control, the mixture compound of thidiazuron and ethephon decreased the kernel moisture content of maize at the mature stage of Xianyu 335 and Xinxin 2 by 6.32% and 5.72%respectively, reduced leaf antioxidant enzyme activity and accelerated the leaf aging. The maturation time of Xianyu 335 and Xinxin 2 advanced for 5 and 6 days, respectively. Mixture compound of thidiazuron and ethephon could significantly increase yield, and Xianyu 335 and Xinxin 2 achieved the yield of 12 899.15 and 12 413.77 kg/hm2, 13.44% and 10.50% higher than the control. Thidiazuron and ethephon had no effects on quality of maize. Correlation analysis showed that seed moisture content was closely related to yield, and the correlation coefficient reached-0.87. 【Conclusion】The effects of accelerate dehydration rate of maize grain, reduce the kernel moisture content of maize at the mature stage and enhance the yield by mixture compound of thidiazuron and ethephon is remarkable. This research provides a theoretical and experimental basis for maize production. [ABSTRACT FROM AUTHOR]

【Objective】 The present paper aims to study the crown pruning methods of Guangxi low-yield and low-efficiency tea garden according to their present planting situation and varieties，and provide a tree crown reconstruction reference for them in the future. 【Method】 Four different tree crown reconstruction methods of light pruning，deep pruning，heavy pruning and collar pruning were conducted and their influences on quality，main biochemical components and yield of tea were analyzed and compared in present work. 【Result】 Among four metliods， the fresh leaf yield of collar pruning method was the highest，which was 1298. 6 kg，followed by 1234. 9 kg of heavy pruning method， no significant difference of yield was found between those two methods， and yield of both methods were above that of CK； the quality of spring green tea and black tea of heav pruning was the best with a comprehensive score above 90，and the cumulative yield of heaving pruning was the highest when reaching the high-yield period after reconstruction 【Conclusion】 The heav pruning method capable of fully restoring the growth of tea trees and reaching the high-yield period with a highest cumulative yield in a short time was able to increase free amino acid， theine，water extract in fresh leaves，giving spring green tea and black tea a mellow taste and wonderful aroma. [ABSTRACT FROM AUTHOR]