氮素亏缺对冬小麦根系生长发育的影响

Effects of Nitrogen Deficiency on the Growth and Development of Winter Wheat Roots

采用盆栽试验研究了不同生育阶段氮素亏缺对冬小麦根系生长发育及活力的影响。结果表明 ,越冬期和拔节期氮素亏缺不仅可以明显减小根长、根条数和根体积 ,而且可以减少根吸收总面积、活跃吸收面积、活跃吸收面积百分比、根比表面及根系活力 ,以越冬期更为显著。在冬小麦根系生长发育较为重要的苗期、越冬期和拔节期 ,前一生育期氮素亏缺 ,后一生育期常量或加倍供氮对根系可表现出一定的补偿效应。

The purpose of this paper is to describe the effect of nitrogen deficiency at different stages of winter wheat on its root growth and development. It was based on a pot experiment that was conducted in No.1 agriculture experiment station of Northwestern Sci-Tech University of Agriculture and Forestry from October, 1997 to June, 1998. The root length, number and volume , the total and active absorbing areas, the root vigor and other items were analyzed. The results indicated that nitrogen deficiency at tillering and jointing stages could make negative effect not only on the root length, number and volume but also on the total and active absorbing areas significantly. The percentage of active absorbing area over the total was declined. The root vigor was also inhibited. The inhibition of nitrogen deficiency at tillering stage was heavier than that at jointing stage. However, the bad impact of the stress at one stage could be compensated to a certain extent at the following stage by supplying normal or doubled amount of nitrogen.