摘要： 为了明确鲜食型甘薯干物质及养分积累分配规律与施氮之间的关系,以鲜食型甘薯(YS25和LS9)为试材,通过盆栽试验研究了不同施氮量对鲜食型甘薯干物质及氮、磷、钾养分积累与分配特性的影响。结果表明,在同一生育期内随着施氮水平的提高,两鲜食型甘薯品种藤蔓干物质及N、P₂O₅、K₂O的积累量均随之增加,而薯块干物质及N、P₂O₅、K₂O的积累量却表现出先增加后降低的趋势,且过量施氮会降低其在薯块的分配率。随施氮量的增加,两鲜食型品种甘薯形成100 kg薯干需吸收的养分量也逐渐增加,且K₂O> N> P₂O₅。总体来说,LS9的N、P₂O₅、K₂O生产效率及干物质生产效率较高,YS25的养分生产效率及干物质生产效率较低,说明LS9为养分生理利用高效率品种,YS25为养分生理利用低效率品种。两鲜食型甘薯品种的养分生产效率和干物质生产效率对施氮的反应基本一致,即施氮显著降低其养分生产效率和干物质生产效率。

关键词: 氮, 鲜食型甘薯, 干物质, 养分, 积累与分配

Abstract: To clarify of the relationship of nitrogen application with dry matter and nutrient accumulation and distribution of fresh-eating sweet potato,the effects of different nitrogen levels on characteristics of dry matter and N,P₂O₅ and K₂O accumulation and distribution of fresh-eating sweet potato have been studied in the pot experiment.The cultivars of fresh-eating sweet potato(LS9 and YS25)were selected as experimental material.The results showed that the accumulation of dry matter and N,P₂O₅,K₂O of YS25 and LS9 shoot were increased with the increase of nitrogen fertilizer application in the same developing stage,while those of YS25 and LS9 root-tuber were increased at first,and then decreased,and their distribution rates of root-tuber were decreased with nitrogen supply.The amounts of nutrients which needed for the formation of 100 kg dried sweet potato of LS9 and YS25 were increased gradually with the increase of amount of N applied,and that was K₂O> N> P₂O₅.In generally,the varieties of LS9 had higher production efficiency of N,P₂O₅,K₂O and dry matter,while YS25 had lower production efficiency of nutrients and dry matter.It showed that LS9 and YS25 had higher and lower physiological use efficiency of the nutrients separately.Responses of production efficiency of nutrients and dry matter of fresh-eating sweet potato (YS25 and LS9) to nitrogen application were almost consistent,namely production efficiency of nutrients and production efficiency of dry matter of N,P₂O₅ and K₂O of sweet potato were decreased by nitrogen application.

Key words: Nitrogen, Fresh-eating sweet potato, Dry matter, Nutrient, Accumulation and distribution

中图分类号: 

• S143.1