Differences in soil physical, chemical and biological properties between paddy–upland and continuous upland rotations will influence nutrient relations and crop growth. With the aim of estimating rapeseed yield perfo...Differences in soil physical, chemical and biological properties between paddy–upland and continuous upland rotations will influence nutrient relations and crop growth. With the aim of estimating rapeseed yield performance in response to fertilization in rice–rapeseed(RR) and cotton–rapeseed(CR) rotations, on-farm experiments were conducted at 70 sites across Hubei province, central China. The economically optimal fertilizer rates of winter oilseed rape in different rotations were determined. Field experiments showed that previous crops significantly influenced seed yields. Without N fertilization,seed yields were significantly lower for the RR rotation than for the CR rotation. The average yield increase ratio and agronomic efficiency associated with nitrogen(N)fertilization in the RR rotation were 96.6% and 6.56 kg kg- 1, significantly higher than those in the CR rotation. No seed yield differences were detected between the two rotations under phosphorus(P) and potassium(K) fertilization. In contrast to the CR rotation, N fertilizer played a more vital role in maintaining high seed yields in the RR rotation owing to the lower indigenous soil N supply. Compared with local N fertilizer recommendation rates for the RR rotation, on average an additional 18 kg N ha- 1was recommended according to the economically optimal N fertilizer rate(EONFR). In contrast, the EONFR was 14 kg N ha- 1lower than the locally recommended N fertilizer rate for the CR rotation. There were no differences between the two rotations for the average economically optimal P and K fertilization rates. Consequently, the average EONFR of winter oilseed rape could be reduced if cotton rather than rice preceded the winter oilseed rape.展开更多
基于"3414"试验设计,研究了沿淮低洼地玉米施肥效应和土壤供肥能力。结果表明,玉米施用氮、磷、钾肥的增产率分别为78.0%、3.7%和16.7%,施用每kg氮、磷、钾肥增产量分别为11.9、2.9、5.3 kg。氮、磷、钾肥对玉米产量的影响表...基于"3414"试验设计,研究了沿淮低洼地玉米施肥效应和土壤供肥能力。结果表明,玉米施用氮、磷、钾肥的增产率分别为78.0%、3.7%和16.7%,施用每kg氮、磷、钾肥增产量分别为11.9、2.9、5.3 kg。氮、磷、钾肥对玉米产量的影响表现为N>K>P。玉米全株分析表明,其籽粒和茎叶氮、磷、钾养分含量分别为12.692、.56、2.84 g kg-1和5.982、.40、18.46 g kg-1,玉米100 kg经济产量所需氮、磷、钾养分量分别为1.77、0.46、2.02 kg。通过数学模拟获得玉米肥料效应方程,并计算出氮(N)、磷(P2O5)、钾(K2O)肥最佳经济施肥量分别为299.1、99.0、175.3 kg hm-2。在本次试验条件下,氮、磷、钾肥利用率平均分别为29.5%、14.8%、35.0%。试验结果还表明,本次玉米试验期间,土壤氮素供应能力较低,磷素供应能力较高,钾素供应能力中等。当季土壤氮、磷、钾养分供应量分别为55.51、1.1、65.4 kg hm-2,土壤氮、磷、钾养分校正系数分别为30.9%1、10%和44.8%。展开更多
基金supported by the National Natural Science Foundation of China(41401324)the earmarked fund for China Agriculture Research System(CARS-13)+1 种基金the Fundamental Research Funds for the Central Universities(2013QC045)the Program for Changjiang Scholars and Innovative Research Team in University of China(IRT1247)
文摘Differences in soil physical, chemical and biological properties between paddy–upland and continuous upland rotations will influence nutrient relations and crop growth. With the aim of estimating rapeseed yield performance in response to fertilization in rice–rapeseed(RR) and cotton–rapeseed(CR) rotations, on-farm experiments were conducted at 70 sites across Hubei province, central China. The economically optimal fertilizer rates of winter oilseed rape in different rotations were determined. Field experiments showed that previous crops significantly influenced seed yields. Without N fertilization,seed yields were significantly lower for the RR rotation than for the CR rotation. The average yield increase ratio and agronomic efficiency associated with nitrogen(N)fertilization in the RR rotation were 96.6% and 6.56 kg kg- 1, significantly higher than those in the CR rotation. No seed yield differences were detected between the two rotations under phosphorus(P) and potassium(K) fertilization. In contrast to the CR rotation, N fertilizer played a more vital role in maintaining high seed yields in the RR rotation owing to the lower indigenous soil N supply. Compared with local N fertilizer recommendation rates for the RR rotation, on average an additional 18 kg N ha- 1was recommended according to the economically optimal N fertilizer rate(EONFR). In contrast, the EONFR was 14 kg N ha- 1lower than the locally recommended N fertilizer rate for the CR rotation. There were no differences between the two rotations for the average economically optimal P and K fertilization rates. Consequently, the average EONFR of winter oilseed rape could be reduced if cotton rather than rice preceded the winter oilseed rape.
文摘基于"3414"试验设计,研究了沿淮低洼地玉米施肥效应和土壤供肥能力。结果表明,玉米施用氮、磷、钾肥的增产率分别为78.0%、3.7%和16.7%,施用每kg氮、磷、钾肥增产量分别为11.9、2.9、5.3 kg。氮、磷、钾肥对玉米产量的影响表现为N>K>P。玉米全株分析表明,其籽粒和茎叶氮、磷、钾养分含量分别为12.692、.56、2.84 g kg-1和5.982、.40、18.46 g kg-1,玉米100 kg经济产量所需氮、磷、钾养分量分别为1.77、0.46、2.02 kg。通过数学模拟获得玉米肥料效应方程,并计算出氮(N)、磷(P2O5)、钾(K2O)肥最佳经济施肥量分别为299.1、99.0、175.3 kg hm-2。在本次试验条件下,氮、磷、钾肥利用率平均分别为29.5%、14.8%、35.0%。试验结果还表明,本次玉米试验期间,土壤氮素供应能力较低,磷素供应能力较高,钾素供应能力中等。当季土壤氮、磷、钾养分供应量分别为55.51、1.1、65.4 kg hm-2,土壤氮、磷、钾养分校正系数分别为30.9%1、10%和44.8%。
