春性和半冬性小麦苗期氮肥吸收效率的差异及其与根系性状的关系

Variations of Uptake Efficiency of Nitrogen Fertilizer and Its Relationship with Root Characteristics at Seedling Stage between Semi-winterness and Springness Wheat Varieties

为探明半冬性与春性小麦苗期氮肥吸收效率的差异及其与根系形态与生理性状之间的相关性,在盆栽条件下,选用半冬性、春性小麦品种各3个,研究了不同氮源(NH_4^+-N、NO_3^--N、NH_4^+-N+NO_3^--N三种类型)供应条件下小麦苗期(6叶期)根系性状的差异及其与氮素吸收能力的关系。结果表明,不同生态类型小麦苗期氮素吸收能力存在显著差异,植株总吸氮量和氮肥吸收效率表现为半冬性类型显著高于春性类型,不同氮源处理变化趋势基本一致。根系性状中,平均根长、根系总长、根系总吸收面积表现为半冬性类型高于春性类型,而根系活跃吸收面积和比表面积表现为半冬性类型低于春性类型,根系重量、氧化力则因供应的氮源不同,生态类型间存在差异。根干重、根系氮积累量与氮肥吸收效率显著相关,其他性状与氮肥吸收效率的相关性不显著。

With three semi-winterness and three springness wheat varieties as experimental materials,a pot experiment was conducted to investigate the root characteristics of uptake efficiency of nitrogen fertilizer（NfUE） of different ecological type wheats and its relationship with NfUE at seedling stage （6-leaf stage）. The differences of root traits and its relationship with nitrogen absorption capacity were determined under different nitrogen application eonditions（NH4^＋-N、NO3^--N and NH4^＋-N ： NO3^--N = 1 ： 1 ）. The results showed that the ability of nitrogen absorption among the different ecological type wheats was different. The amount of nitrogen absorption and nitrogen uptake efficiency of semi-win- terness wheat varieties was higher than that of springness wheat varieties under different nitrogensupplied conditions. The average root length, the total root length and the total absorption area of semi-winterness wheat varieties were higher than those of springness wheat varieties. However, the active absorption area and specific surface area of semi-winterness wheat varieties were lower than those of springness wheat varieties. The root weight and oxidation activity were different among dif- ferent ecological type wheat varieties because of different nitrogen application.