地黄适宜磷肥用量及基追比例的研究初探

Initial Studied on Optimal Phosphorus Application Rate and Ratio Between Basal and Topdressing for Rehmannia glutinosa Libosch Production

适宜的磷肥用量及基肥和追肥比例不仅可以提高地黄的产量,改善品质,还能增加药农的收入。通过两年的田间试验,总结地黄干物质积累及磷素需求特征,研究磷肥总量及基追比例对地黄生长和收获期产量的影响。结果表明无论是地黄总生物量还是磷素吸收量,积累高峰均出现在地黄拉线期至块根膨大期。增加磷肥施用量,特别是拉线期磷肥施用比例,能明显促进地黄根叶比,增加收获期产量。表明在当前生产条件下,地黄优化磷肥用量为72～88 kg P2O5/hm2,拉线期基肥和追肥比例应为1∶1,可提高产量。

Optimal phosphorus （P） management and ratio between basal and topdressing can not only increase root yield of Rehmannia glutinosa Libosch at harvest, improve its quality, but also increase famers＇ income. Two years＇ on- farm field experiments was conducted to summarize the characteristics of dry-matter accumulation and P demand, to study the influence of optimal total P fertilizer quantity and ratio between basal and topdressing fertilization on the growth and yield of Rehmannia glutinosa Libosch. Whatever dry-matter and P uptake, the accumulation peaks occurred from root elongate to root enlargement periods. Increasing the P fertilizer amount, especially P fertilization at root elongate phase, could significantly promote the roots/leaves ratio, and increase root yield at harvest. We understand that under present production conditions, the optimal P fertilizer amount is 72 -88 kg P2OJhm2 , and the ration between basal and topdressing fertilization should be 1：1 at root elongate phase.