指数施肥对美国山核桃幼苗根系形态的影响

摘要

An exponential fertilization trail was conducted to assess the effects on different nitrogen levels on the root morphology (root length, root surface area an, root volume and root biomass)of pecan seedlings.The results show:(1)The root length,root surface area,root volume and root biomass of pecan seedlings were decreased with the increase of N supply. Effect of N total 100 mg for a plant was best to pecan seedlings,by the end of the study,the root length,root surface area, root volume and root biomass of pecan seedlings were(4 882±356)cm,(830±66)cm2,(12.29±0.19)cm3,(3.84±0.11) g, which were 1.53,1.55,1.79,and 1.59 times of the CK treatment,respectively.(2)The specific root length of the pe-can seedlings was decreased with the increase of the amount of nitrogen.(3)The fertilization rate of 100-200 mg for a plant was best to the growth of root morphology of pecan seedling.%为探究施肥对美国山核桃幼苗根系形态的影响和适宜施氮量,以1年生美国山核桃实生苗为试验材料,运用指数施肥法,探讨不同施氮量对美国山核桃根系形态(根长、根表面积、根体积、根生物量和比根长)的影响.结果表明:(1)美国山核桃根系形态指标随着施氮量的增加呈现递减趋势,N100处理的所有指标取得最大值;N100处理的总根长、根表面积、根体积、根生物量分别达到(4882±356)cm、(830±66)cm2、(12.29±0.19)cm3、(3.84± 0.11)g,分别为对照组的1.53、1.55、1.79、1.59倍.(2)美国山核桃幼苗比根长随着施氮量的增加而减小.(3)最有利于美国山核桃幼苗根系生长的施氮量为100~200 mg· 株-1.