不同氮肥用量对大白菜‘早熟五号’生长及氮磷钾积累的影响

Effect of Different N Levels on Growth and Accumulation of N,P and K in Leaves of Chinese Cabbage‘Zaoshu No.5'

以大白菜‘早熟5号’为试材,利用盆栽试验,研究了不同氮素用量对其生物量、植株氮磷钾质量分数及积累量的影响。结果表明:在生长期,地上部单株鲜(干)质量均成倍增大,N3处理的鲜(干)质量均为最大值,但至收获期,单株鲜(干)质量,氮、磷、钾质量分数和积累量在不同处理间的差异并不显著,鲜质量每株介于41.0~49.8g,氮、磷、钾质量分数为25.5~26.4、3.4~3.6、27.1~29.2mg·g^(-1),氮、磷、钾积累量每株介于61.6~66.8、8.3~9.1、66.2~73.8mg;随着施氮量的增加,氮肥农艺利用率和氮素吸收效率均显著降低。因此,在大白菜生产中以每盆2.0g的纯氮用量(N3处理),理论N素83.4kg·hm^(-2)为宜。

With Chinese cabbage of ＇Zaoshu No. 5＇ as material, the effect of fertilizers at different N levels on biomass, accumulation of N,P,K in leaves Chinese cabbage were studied by pot experiments. The results showed that fresh （dry） weight of the upper ground part increased exponentially, and the highest level was found in N3 treatment during the growing period, however, it was not significantly different among different treatments at the harvest time. For all treatments, fresh weight was between 41.0- 49.8 g per plant, mass fraction of N, P, K was 25. 5- 26.4,3.4- 3.6, 27. 1-29.2 mg · g^-1 , and the accumulation of N, P, K was 61.6 - 66.8, 8. 3 - 9. 1, 66.2 - 73. 8 mg per plant, respectively. With the increase of the nitrogenous fertilizer, the agronomic efficiency and nitrogen uptake efficiency decreased significantly. Therefore,the amount of pure nitrogen as 2. 0 g in a basin （N3 treatment） ,theoretical N 83. 4 kg · hm^- 2 was appropriate.