Regulation of Key Enzymes of Sucrose Biosynthesis in Soybean Leaves Effect of Dark and Light Conditions and Role of Gibberellins and Abscisic Acid

摘要: An important part in the understanding of regulation carbon partitioning within leaf is to investigate endogenous variations parameters related metabolism. This study diurnal changes activities sucrose-synthesizing enzymes and levels nonstructural carbohydrates intact leaves field-grown soybean plants (Glycine max [L.]) showed pronounced fluctuations sucrose phosphate synthase (SPS) activity. However, there was no distinct change activity fructose-1,6-bisphosphatase (F1,6BPase). SPS from grown controlled environments presented two peaks during light period. In contrast plants, F1,6BPase growth chamber-grown manifested one peak first half under both conditions, starch accumulation rates were highest early hours By end dark period, most depleted. A pattern abscisic acid (ABA) also observed all growing conditions. Either imposition water stress or exogenous applications ABA inhibited SPS-extractable increased following deficit but did not response treatment. Gibberellin application sucrose. Both gibberellic (10−6m) gibberellins 4 7 (10−5m) had an inconsistent effect on F1,6BPase. Correlation studies between suggest that these are coordinated their function, factors regulate them may be because they respond differently certain environmental physiological changes.