水稻植株对于土壤氮和肥料氮的吸收同化和分配

STUDY ON THE ABSORPTION, ASSIMILATION AND PARTITIONING OF SOIL N AND FERTILIZER N BY RICE CROP

用^(15)N示踪法研究水稻植株对于土壤氮和肥料氮的吸收、同化和分配,着重分析稻谷干物质和含氮量的来源。结果表明:氮肥提高植株营养体的物质积累、增强上3叶和根系的生理功能;从抽穗至成熟阶段,上3叶的同化物运转于稻谷的,由对照的27％～30％增加到40％～56％,氮从29％～32％提高至32％～37％;植株吸收的氮(土壤氮和肥料氮)占稻谷中的激发氮占3l％～39％,这二部分氮高的稻谷产量也高。

The pot experiments were carried out to investigate the absorption, assimilation and partitioning of the soil N and fertilizer N labeled with ^(15)N by the rice crop. The results indicated that the N fertilizer applied at planting time increascd the absorption and assimilation of N by the roots and the top three leaves.During the grain filling period the assimilates transferred from the top threc leaves to the grain increased from 27%～30% to 40%～56% as compared with the check treatment and N increased from 29%～32% to 32%～39%. The 'priming effect' of fertilizer on soil N was significant so that the amount of grain N from the priming effect was 31%～39%.