山药珠芽生长过程中激素和糖类物质含量的变化

 测定了不同生长阶段的山药（Dioscorea opposita）珠芽内源激素IAA、ZR、DHZR、GA₃和ABA的含量，以及还原糖、可溶性糖、淀粉和干物质的含量，研究其变化规律。结果表明，珠芽生长期IAA和DHZR含量低，变化小。ZR的含量一直比DHZR高，且变化大，尤其在珠芽生长初期含量下降快。与其它激素相比，GA₃含量较高，生长初期呈上升变化，随后缓慢下降，当生长停止时其含量仍较高（1 220.7 ng · g^-1）。珠芽完全变褐前，ABA的含量在730.9 ~ 954.9 ng · g^-1间波动，在珠芽完全变褐至生长停止期间急剧上升。珠芽开始褐变前，还原糖含量迅速下降，以后变化较小。珠芽生长过程中可溶性糖含量呈曲线上升；淀粉和干物质含量呈直线缓慢上升，当珠芽成熟时可溶性糖、淀粉和干物质含量达到最高。山药珠芽的生长需要高水平的GA₃和ZR，当GA₃/ABA小于1时，珠芽趋于成熟；茎蔓枯黄珠芽才停止生长，糖、淀粉等物质的积累才终止。

Variation of Endogenous Hormone and Carbohydrate Contents in Growing Yam Bulbils

Contents of endogenous hormones IAA,ZR,DHZR,GA3,ABA,reducing sugar,soluble sugar,starch and dry matter in yam(Dioscorea opposita)bulbils were tested over developmental cycle.The results showed that concentration of IAA was low and varied gently,so did that of DHZR,while ZR content was higher than DHZR content throughout bulbil developing stage and changed more sharply especially at early stage.The content of GA3,compared with other hormone contents,was very high throughout bulbil developing stage,it maintai...