蛋白质含量不同的大豆籽粒形成过程中内源激素活性的变化

ENDOGENOUS HORMONE ACTIVITIES DURING SEED DEVELOPMENT OF SOYBEAN GENOTYPES DIFFERING IN PROTEIN CONTENT

对蛋白质含量不同的大豆籽形成过程中内源激素活性变化的研究表明 :GA3活性在不同基因型大豆中存在着差异 ,但活性高峰期和总的变化规律在品种 (系 )间是相似的。高蛋白和中蛋白含量的品种在籽粒发育初期就表现出较高的 GA3活性 ,高蛋白和中蛋白品种的 i PAs和 IAA活性在籽粒形成过程中出现两个高峰期 ,而低蛋白品系的 IAA只出现一个高峰期。中蛋白品种的 i PAs活性在籽粒形成过程中明显高于其他类型的品种。而低蛋白品系的 IAA活性在籽粒形成过程中都明显高于高、中蛋白含量的品种。由此初步认为 ,内源激素活性变化与不同基因型大豆的蛋白质积累有关 ,单一 GA3活性和 IAA活性参与蛋白质积累的调节激素之间的平衡 ,尤其是 R5 期后 2 0天 IAA/i PAs的比值与成熟期籽粒蛋白质含量关系密切 。

Endogenous hormone activities during seed development of three soybean genotypes differing in protein content were investigated. The results show that there are significant genotypic differences in GA 3 activities during seed development, but activity peak and general trend are similar among cultuvars. GA 3 activities at early stages of seed development are evidently higher in high protein and middle-protein cultivars. There are also two peaks in iPAs and IAA activities during seed development in the middle and high protein cultivars, but only one peak of IAA activity in low-protein line. iPAs activites of middle protein cultivar are significantly higher than those of other two cultivars, but IAA activities of low-protein line at all stages during seed development are significantly higher than those of middle-and high-protein cultivars. It is conclude that hormones are involved in the accimilation of protein, and higher GA 3 activity is responsible for high-protein, higher IAA activity is responsible for low-protein, and the ratio of IAA/iPAs at 20 days after R 5 stage is negatively carrelated to protein content at maturity.