我国不同年代玉米品种生育全程根系特性演化的研究

Evolution of Root Characters during All Growth Stage of Maize Cultivars in Different Eras in China

对我国 2 0世纪 5 0、70和 90年代玉米品种的根系生理特性演化趋势研究表明 ,我国不同年代的品种根系特性存在显著差异 ,主要表现在根系的吸收和合成功能上。在生长发育前期 ,随着品种年代的进展 ,根系活跃吸收面积、单株根条数以及根系SOD和CAT活性显著增加 ,且不同年代的品种间差异显著 ;在生长发育后期 ,随着品种年代的进展 ,高层节根数量和单株伤流液量明显增加 ,根系合成氨基酸的能力增强 ,对元素Zn、B、Mn、P、Mg、Ca和K的吸收速率明显增大 ,单株根干重和冠根比 (C R)

The root characters of maize cultivars which came from 50's, 70's and 90's in China in different eras was evaluated in this study. The results showed that the vigor of the root system was distinct remarkably in different eras. During the earlier growth stage, the active surface area, the activity of SOD & CAT of root system and the number of root per plant all increased clearly with the improvement of cultivars, and the above root characteristics of the cultivars in different eras was extremely different. During the later growth stage, the number of root in top position and the quantity of wounding flow per plant all increased obviously with the cultivar developed, the synthetic ability of amino acid and the absorbing rate of Zn, B, Mn, P, Mg, Ca and K increased greatly, the dry weight of root per plant and ratio of canopy/root(C/R) also increased distinctly.