木薯内源激素含量与块根淀粉积累关系研究

为探讨木薯内源激素（IAA、ABA、GA3、CYT）含量和块根淀粉积累的关系,分别对高低淀粉木薯品种不同时期块根、茎秆、叶片内源激素（IAA、ABA、GA3、CYT）和块根淀粉含量变化进行研究。结果表明：块根、茎秆、叶片中IAA含量变化趋势一致,在块根形成期达到最大值;块根、茎秆内ABA、GA3,叶片内ABA与块根淀粉含量呈极显著正相关关系,其中茎秆ABA、GA3主要是通过影响光合产物的装载和运输来促进块根淀粉的积累;在块根形成期和膨大期,高淀粉木薯品种‘辐选01’块根内CYT含量高且持续时间长。叶片中IAA、CYT、GA3与块根淀粉含量呈极显著负相关关系,随着块根成熟,这3种内源激素都有不同程度的上升趋势,可能与它抗衰老的能力有关。在块根膨大期,‘华南124’茎秆GA3含量极显著高于‘辐选01’,‘辐选01’块根、叶片ABA含量在生长后期显著高于‘华南124’,说明低淀粉木薯品种后期不易早衰,但地上部分生长过旺不利于块根淀粉积累。

Study on Endogenous Hormones Content and Its Relations to Tuberous Root Starch Accumulation in Cassava

The endogenous hormones (IAA, ABA, GA3, CYT) content in the root, stem, leaf and the change of root starch content of different starch content of cassava varieties at different periods were studied in order to explore endogenous hormones (IAA, ABA, GA3, CYT) content of cassava and its relation to tuberous root starch accumulation. The main results were showed as follow: the content of IAA in root, stem, leaf were similar which were peaked at the beginning of the root form. High significant and positive correlation between the content of ABA, GA3 in the root, stem, the content of ABA in the leaf and the contents of starch of tuberous root. ABA, GA3 in the stalks mainly facilitate the tuberous root starch accumulation through the influence of photosynthesis product loading and transport. In root formation and expansion period, the content of CYT in root tubers of the high starch cassava varieties 'Fuxuan01' was higher and longer duration that SC124. High significant negative correlation between IAA, CYT, ABA of the leaf and the contents of starch of tuberous root. As the root mature, this three endogenous hormones had the varying degree rise, which may be related to its anti-aging ability.In the Root tuber of maturity, the content of GA3 in stem SC124 was significantly higher than 'Fuxuan 01', the ABA content in root and leaf of 'Fuxuan 01' was significantly higher than SC124 at later growth stage. It showed that low starch cassava varieties was not easy to premature aging, but the excessive growth of the ground part was bad for tuberous root starch accumulation.