Search

【Objective】The present paper aimed to clarify the comprehensive soil fertility status of pitaya orchards in Hainan province, and the spatial distribution and changing trend of soil nutrients in pitaya orchards in Hainan province were analyzed and predicted by means of survey sampling and statistical methods, so as to provide the basis for scientific fertilization and soil management of pitaya orchards.【Method】60 soil samples were collected from pitaya orchards in the main producing areas of Hainan province.Soil pH, organic matter, available nitrogen, available phosphorus, available potassium, exchangeable calcium, exchangeable magnesium, available copper and available zinc were used as evaluation indicators.Inverse distance weight interpolation method（IDW） was used to analyze the spatial distribution of each index, and used the factor analysis method combined with IDW to evaluate and predict the comprehensive soil fertility of the pitaya orchards in the survey area.【Result】The orchard soil in the survey area was neutral and slightly acidic, and 50% of the soil samples, pH were lower than 6.5; The organic matter content was moderately low, and some areas of Ledong and Sanya were insufficient; The average value of alkaline hydrolysis nitrogen was only 79.17 mg/kg, and the soil in the survey area was relatively lack of alkali-hydrolyzable nitrogen; The content of available phosphorus and available potassium were both high, and the average available phosphorus was 119.06 mg/kg, far exceeding its environmental risk threshold（60 mg/kg）; Orchards in the survey area the content of trace elements in the soil was relatively abundant. The IDW prediction map showed that the content of trace elements in Dongfang and Lingshui was high, and the content of Ledong and Sanya was low; Based on the analysis of the comprehensive score IFI, the results of the comprehensive fertility prediction of pitaya orchards in the entire study area using IDW showed that the eastern part of the study area, the comprehensive soil fertility of the orchards in the eastern and western regions of the study area was relatively high, while the soil comprehensive fertility of the orchards in the central part of Ledong and Sanya was relatively low.【Conclusion】The pitaya orchards in Ledong and Sanya still need to increase the input of organic fertilizers or increase the application of lime to improve the soil pH and supplement the medium and trace elements; The orchards in the survey area need to increase the input of nitrogen fertilizer and control the application of phosphate fertilizer. [ABSTRACT FROM AUTHOR]

[Objective] The present paper aimed to study the impact of organic and inorganic combined application on the organic carbon composition, carbon bank management index and organic carbon functional group of tobacco planting soil in Wuxi county, so as to provide reference for improving the quality of tobacco planting soil and reasonable fertilization. [Method] Four treatments were set up under the condition of constant nitrogen input in field experiment: chemical fertilizer（CF）, chemical fertilizer with mushroom slag organic fertilizer（CMO）, chemical fertilizer with high carbon-based fertilizer（CHB）, and chemical fertilizer with biological organic fertilizer（CBO）. The effect of organic and inorganic application on soil carbon reservoir was studied by measuring total organic carbon and active carbon functional group structure using Fourier infrared spectrometry（FTIR）. [Result] （i） Compared with single organic fertilizer, the soil supplemented with organic fertilizer was slightly increased, and there was no significant difference between the treatments, significantly increased the output value on flue-cured tobacco leaf;（ii） The DOC, MBC content of the soil active carbon bank treated with organic fertilizer was significantly higher than that of single chemical fertilizer treatment. Among them, CMO treatment showed the largest increase in soil DOC content, thus being 67. 13%, 12. 84%, and 28. 54% higher than CF, CHB, CBO, respectively. CBO treatment showed the most increase in soil MBC content, with soil MBC content increasing 42. 32% compared to CF and CHB treatment showing 11. 43% higher soil EOC compared to CF;（iii）Among the three organic fertilizers, the DOC distribution of DOC, CMO, CBO, EOC, and the carbon bank management index of CHB treatment was significantly greater than CF and CMO;（iv） The structure difference of each treated organic carbon functional group was small, which mainly included phenols, aromatic hydrocarbons, olefins and mesamides. The relative peak area at 1634 cm-1 was associated significantly positively with soil MBC content, and that at 468 cm-1 was associated significantly negatively with soil TOC content. [Conclusion] Compared with single organic fertilizer, soil organic residue organic fertilizer significantly improved soil DOC and MBC content and high carbon-based fertilizer significantly improved soil EOC content and carbon bank management index. Short-term organic and inorganic distribution had little impact on organic carbon functional groups. However, the peaks at 1634 and 468 cm-1 were significantly associated with the soil TOC and MBC content. At the same time, organic-inorganic fertilizer significantly increased the yield and output value of flue-cured tobacco. [ABSTRACT FROM AUTHOR]

【Objective】 This paper aimed to explore effects of reduced chemical fertilizer and soil texture on yield, quality and nitrogen（N）, phosphorus（P） and potassium（K） fertilizer utilization rate of flue-cured tobacco. 【Method】 Using flue-cured tobacco variety K326 as material, a field experiment was established in sandy soil, clay soil and heavy loam in Qujing tobacco production site, and six fertilization treatments were set up, i.e., T1（CK）（conventional dosage of N, P, K）, T2 and T3（deduced fertilizer N, P, K proportion by 10% and 20%, respectively）, T4 and T5（organic fertilizer replacing 10% and 20% chemical fertilizer, respectively） and T6（no manure or fertilizer）. 【Result】Compared with treatment T1（CK）, treatments T2, T3 significantly improved grade, yield, economical output and N, P, K use efficiency of tobacco leaves in sandy soil. Meanwhile, treatments T2, T3 increased contents of potassium, decreased total sugar, reducing sugar. The contents of total nitrogen, nicotine and water-soluble chloride in the middle and upper parts of leaves were not significantly affected; and the chemical composition was more balanced under T2 and T3. Compared with treatment T1（CK）, treatment T2 and T5 did not significantly improved growth of the tobacco plants in clay soil, but the proportion, yield, output and N, P, K use efficiency under T2 and T5 in tobacco leaves were significantly higher than that of T1（CK）, and the chemical composition of middle and upper position leaves was more balanced. Compared with T1（CK）, treatments T2, T3, T5 had no effect on tobacco plant growth in heavy loam, but improved the proportion of products, yield, output, N, P, K use efficiency of tobacco. Furthermore, the contents of total sugar, reducing sugar of middle and upper part leaves were increased under T2, T3 and T5. The total nitrogen, nicotine, potassium and water-soluble chloride were not affected by treatments. And treatments T2, T3 significantly improved the balance of chemical composition of tobacco leaves. Under the same N, P and K application rate, the N and P uptake and use of tobacco plants in different soils could be sorted as the following: Sandy soil>heavy loam>clay soil, and K use efficiency as the following: Heavy loam>clay soil>sandy soil. 【Conclusion】Based on the current N, P and K usage of tobacco in farmlands, the potential N, P and K proportion of chemical fertilizer reduction（CR） or replacement with organic fertilizer（ROR） in sandy soil was 10%. The N, P and K proportion of CR or ROR in clay soil was 10%-20%. The potential reduction of N, P and K fertilizer in heavy loam was 10%, and the potential proportion ROR was 10%-20%. [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 compare the effect of different passivation materials on Bletilla striata on the accumulation of Cd under cadmium stress, so as to provide theoretical support for promote quality of B. striata cultivated in soil polluted by Cd.[Method] A pot-culture experiment was carried out, taking B. striata as test material, using external sources with adding 1.5 mg/kg Cd to simulate heavy Cd contamination of soil, the pH of soil, effective Cd and Cd content in B. striata were analyzed and determined after applying different passivation materials（ 5% silicon-calcium fertilizer, 5% cattle manure organic fertilizer, 5% corn straw biochar, 5% phosphorous-containing substances, 5% silicon-calcium fertilizer+5% corn straw biochar, 5% cattle manure organic fertilizer+5% phosphorous-containing substances+5% silicon-calcium fertilizer+5% cattle manure organic fertilizer). [Result] Among different passivation materials, 5% cattle manure organic fertilizer and 5% corn straws biochar were effective in increasing the biomass in underground stem and whole plant of B. Striata. Compared with CK, the biomass of the underground tubers increased by 62.87% and 59.18%, respectively, and the whole plant biomass increased by 57.36% and 46.07%, respectively. The soil pH treated with cattle manure organic fertilizer+silicon-calcium fertilizer, silicon-calcium fertilizer + corn straw biochar and silicon-calcium fertilizer was higher than that of CK, which increased by 3.84, 3.70 and 3.67 units, respectively. The content of effective Cd in soil treated with silicon-calcium fertilizer, cattle manure organic fertilizer+silicon-calcium fertilizer, silicon-calcium fertilizer+corn straw biochar was lower than that of CK, which decreased by 92.86%, 89.29% and 87.50%, respectively. The content of Cd in root, tuber and leaf of B. striata was the lowest treated with cattle manure organic manure + ilicon-calcium fertilizer, as the decrease rate was 97.60%, 88.80% and 95.29%, respectively. The enrichment capacity of Cd in parts of B. striata were of root > tuber > leaf, and the enrichment capacity of Cd in parts B. striata was the lowest treated with cattle manure organic fertilizer+silicon-calcium fertilizer. [Conclusion] Applying 5% cattle manure organic fertilizer and 5% corn straw biochar have better effect in increasing yield of B. striata tuber. Applying 5% cattle manure organic fertilizer +5% silicon-calcium fertilizer, 5% corn stalk biochar +5% silicon-calcium fertilizer and 5% silicon-calcium fertilizer have better passivation effect on heavy Cd pollution, and applying 5% cattle manure organic fertilizer +5% silicon-calcium fertilizer has best blocking effect on Cd in parts of B. striata. [ABSTRACT FROM AUTHOR]

[Objective] In order to explore the effects of low nitrogen stress on the growth and soil nutrients of tartary buckwheat in the hilly and gully regions of the Loess Plateau, the present paper determined plants and soil characteristics of tartary buckwheat with different nitrogen stress among the whole growth period It could provide a scientific basis for the optimal management of farmland nitrogen fertilizer in the loess hilly and gully region. [Method] The study took different nitrogen buckwheat (Heifeng No. 1, HF, intolerant to low nitrogen, Diqing Tartary Buckwheat, D Q, tolerant to low nitrogen) as the research objects, and set 3 levels of nitrogen application as follows : 0 kg/hm² (NO, no nitrogen treatment), 80 kg/hm² (Nl, low-nitrogen treatment), 160 kg/hm² (N², normal nitrogen treatment). Plant indexes (plant height, stem thickness, leaf area) and soil characteristics (soil water content, pH, organic matter, alkali-hydrolyzed nitrogen, available phosphorus, available potassium, total nitrogen, total phosphorus, total potassium) were determined during the whole growth periods. [Result] (i) Cultivar, nitrogen treatment and the interaction between the two had extremely significant effects on tartary buckwheat plants (P < 0. 01). Under Nl treatment, the plant height, stem thickness and leaf area of DQ in the seedling stage were 9. 7 %, 10. 5 %, and 17. 7 % higher than that of HF. The plant height and stem thickness of DQ in the flowering stage were 9. 5 % and 7. 4 % higher than that of HF. The stem thickness and leaf area of DQ were 5. 4 % and 3 6. 2 % higher than those of HF. (ii) The cultivars, nitrogen treatments and the interaction between the two had a significant impact on soil nutrients (P < 0. 01). After the growth period, the soil nutrient indexes of the two cultivars were lower than those of the sowing period, but soil organic matter, available nitrogen, available phosphorus, available potassium, total nitrogen, and total potassium of DQ were higher than those of HF under Nl treatment of98. 8%, 11. 6%, 44. 7%, 11. 6%, 80. 41%, 4. 2%, respectively. [Conclusion] The DQ (low nitrogen tolerant) has better water conservation and green manure benefits than HF (intolerant to low nitrogen) as its larger leaf area and stem thickness could buffer the direct erosion of rainfall on the ground and resist wind to prevent plant lodging. In addition, the rhizosphere soil nutrient content of DQ was higher than HF after being harvested which could reduce the fertilizer consumption in the next season and was also more conducive to the sustainable development of agriculture. [ABSTRACT FROM AUTHOR]

[Objective] In order to explore the effects of low nitrogen stress on the growth and soil nutrients of tartary buckwheat in the hilly and gully regions of the Loess Plateau, the present paper determined plants and soil characteristics of tartary buckwheat with different nitrogen stress among the whole growth period It could provide a scientific basis for the optimal management of farmland nitrogen fertilizer in the loess hilly and gully region. [Method] The study took different nitrogen buckwheat (Heifeng No. 1, HF, intolerant to low nitrogen, Diqing Tartary Buckwheat, D Q, tolerant to low nitrogen) as the research objects, and set 3 levels of nitrogen application as follows : 0 kg/hm² (NO, no nitrogen treatment), 80 kg/hm² (Nl, low-nitrogen treatment), 160 kg/hm² (N², normal nitrogen treatment). Plant indexes (plant height, stem thickness, leaf area) and soil characteristics (soil water content, pH, organic matter, alkali-hydrolyzed nitrogen, available phosphorus, available potassium, total nitrogen, total phosphorus, total potassium) were determined during the whole growth periods. [Result] (i) Cultivar, nitrogen treatment and the interaction between the two had extremely significant effects on tartary buckwheat plants (P < 0. 01 ). Under Nl treatment, the plant height, stem thickness and leaf area of DQ in the seedling stage were 9. 7 %, 10. 5 %, and 17. 7 % higher than that of HF. The plant height and stem thickness of DQ in the flowering stage were 9. 5 % and 7. 4 % higher than that of HF. The stem thickness and leaf area of DQ were 5. 4 % and 3 6. 2 % higher than those of HF. (ii) The cultivars, nitrogen treatments and the interaction between the two had a significant impact on soil nutrients (P < 0. 01). After the growth period, the soil nutrient indexes of the two cultivars were lower than those of the sowing period, but soil organic matter, available nitrogen, available phosphorus, available potassium, total nitrogen, and total potassium of DQ were higher than those of HF under Nl treatment of98. 8%, 11. 6%, 44. 7%, 11. 6%, 80. 41%, 4. 2%, respectively. [Conclusion] The DQ (low nitrogen tolerant) has better water conservation and green manure benefits than HF (intolerant to low nitrogen) as its larger leaf area and stem thickness could buffer the direct erosion of rainfall on the ground and resist wind to prevent plant lodging. In addition, the rhizosphere soil nutrient content of DQ was higher than HF after being harvested which could reduce the fertilizer consumption in the next season and was also more conducive to the sustainable development of agriculture. [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]