不同直链淀粉含量水稻籽粒淀粉积累及其相关酶的活性变化研究

The research on the accumulation of grain starch and change of related enzymes activity in rice with different amylose contents

以4个不同直链淀粉（AC）含量水稻品种为研究材料,研究籽粒淀粉积累规律及其相关酶的活性变化,并分析了两者之间的相关性.结果表明直链淀粉积累速率、支链淀粉积累速率、颗粒结合型淀粉合成酶（GBSS）和可溶性淀粉合成酶（SSS）活性均呈单峰曲线变化.所有水稻品种直链淀粉含量在花后5～15 d增幅最大;支链淀粉含量在花后5～20 d有一个极显著增加的过程,B6优4761增幅最大.Logistic方程拟合淀粉积累过程发现,直链淀粉积累量的高低主要取决于最大积累速率的高低,而最大积累速率出现的早晚和活跃积累天数的长短决定了支链淀粉积累量的高低.高AC含量品种菲优188直链淀粉积累量、积累速率及GBSS活性最大值显著大于其它水稻品种;糯稻品种成糯88在花后15 d的支链淀粉积累量和积累速率最大,但其籽粒SSS活性较低.灌浆后期,高AC含量品种菲优188的籽粒千粒重明显大于其余水稻品种.相关分析表明,所有水稻品种籽粒淀粉积累速率均与GBSS、SSS活性呈正相关,说明籽粒淀粉积累量的高低还受到GBSS和SSS活性的影响.

Four rice varieties with different amylose contents were used to study the pattern of grain starch＇s accumulation and the activity of related enzymes,and the correlation between the pattern and activity was analyzed.The results showed that accumulation rate of amylase and amylopectin,granule bound starch synthase（ GBSS） and soluble starch synthase（ SSS） changed in the pattern of a single peak curve during grain filling. The growth of amylose content reached to the maximum in 5—15 days after flowering in all rice varieties,and was highest in Feiyou188,lowest in Chengnuo88. The content of amylopectin increased significantly in 5—20 days after flowering（ P〈0. 01） and was highest in B6you4761. The accumulation courses of both amylopectin and amylose were well fitted to the logistic equation. The simulation of accumulation process discover that the maximum accumulation rate appears with higher maximum accumulation amount of amylose; and the accumulation amount of amylopectin is positive correlated with the an earlier appearance of the maximum accumulation rate and a longer active accumulation days.The accumulation amount and rate of amylose,GBSS activity in Feiyou88 with a high AC content were significantly higher than other varieties. The amylopectin accumulation and accumulation rate in Chengnuo 88 reached to the highest within 15 days after anthesis,but its SSS activity in grain was low. The 1000-grain weight of Feiyou88 was higher than that of other varieties during end filling stage. Correlation analysis indicates that there is a positive correlation between accumulation rate of grain starch and the activity of GBSS and SSS in all rice varieties,which illustrates that activity of GBSS and SSS affect the accumulation of grain starch.