不同铵硝比的氮素营养对菠菜产量和可溶性草酸含量的影响

【目的】采用水培试验，研究了不同铵硝比的氮素营养对菠菜产量和可溶性草酸含量的影响。【方法】用5种不同铵硝比的氮素营养处理菠菜幼苗，36d后采集样本，观察不同铵硝比的氮素营养对菠菜产量和草酸含量的影响。【结果】（1）从铵硝比100:0到0:100，随着营养液中硝态氮比例的增加，菠菜地上部鲜重不断增加，铵硝比为0:100时，菠菜的产量最高，地上部单株鲜重平均值为6.2g，分别是铵硝比为25:75和100:0处理的1.2倍和5.9倍；（2）随着铵硝比的降低，菠菜茎叶中可溶态草酸的含量是逐渐降低的，在铵硝比为25:75时，菠菜茎叶中草酸含量最低，之后又呈现上升趋势。营养液中硝态氮占全氮的百分数和菠菜茎叶中可溶态草酸含量之间呈现出显著的二次曲线相关。【结论】铵硝比越低，菠菜产量越高；铵硝比为25:75时，菠菜茎叶中草酸含量最低

Effects of NH4+-N/ NO3--N ratios on Yield and Soluble Oxalate Content of Spinach (Spinacia oleracea L.)

【OBJECTIVE】The objective of this investigation was to study the effects of NH4+-N/ NO3--N ratios on the yield and soluble oxalate content of spinach fresh shoot. 【METHOD】Spinach seedling was treated with different ratios of NH4+-N/ NO3--N，the yield and soluble oxalate content of spinach fresh shoot were observed after 36 days. 【RESULTS】Results showed that (1) from NH4+-N/ NO3--N ratio of 100:0 to the ratio of 0:100, spinach shoot fresh weight gradually increased with the increase of the percent of NO3--N in the total nitrogen. Spinach supplied with NO3--N as its sole nitrogen source had the highest yield; (2) with the decrease of the NH4+-N/ NO3--N ratio, the soluble oxalate content of spinach shoot gradually decreased. As the NH4+-N/ NO3--N ratio of 25:75, the soluble oxalate content was the lowest, with the ratio further smaller, the oxalate content was reversed to increase. There was a significant quadric relationship between the percent of in the total nitrogen and soluble oxalate content of spinach shoot. 【CONCLUSION】The yield of spinach was increasing with the NH4+-N/ NO3--N ratio increasing, the oxalate content was the highest when the ratio of NH4+-N/ NO3--N was 25:75