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【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] 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 ] 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]

[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 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] 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 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]