不同绿豆品种籽粒形成过程中淀粉积累特性

Starch accumulation characteristics of different mung bean varieties during grain formation

关键词:  绿豆  淀粉合成  淀粉合成相关酶  直链淀粉  支链淀粉

Key words:  mung bean  starch synthesis  amylosynthease  amylose  amylopectin

摘要:

为探究绿豆籽粒灌浆过程中淀粉积累的特性，选用‘绿丰2号’、‘安绿7号’、‘冀0816毛-3’和‘安康绿豆’4个绿豆品种为材料，对开花后绿豆籽粒形成过程中淀粉代谢相关酶活性及直链淀粉、支链淀粉和总淀粉的积累变化进行测定，用Logistic方程拟合淀粉积累过程，并进行相关分析。结果表明，绿豆籽粒形成过程中，直链淀粉、支链淀粉及总淀粉积累量均不断增加。随着籽粒灌浆，4个绿豆品种的淀粉合成相关酶腺苷二磷酸葡萄糖焦磷酸化酶(AGPase)、颗粒结合淀粉酶(GBSS)、可溶性淀粉合成酶(SSS)和淀粉分支酶(SBE)均呈先上升后下降趋势。籽粒淀粉积累符合Logistic方程。曲线拟合分析显示，大粒型绿豆‘安绿7号’和‘冀0816毛-3’最大淀粉积累速率均出现在花后8~11 d，小粒型绿豆‘绿丰2号’和‘安康绿豆’最大灌浆速率均出现在花后15~18 d。相关分析表明，绿豆籽粒中AGPase酶活性与淀粉积累速率呈极显著正相关。AGPase是绿豆淀粉合成的关键酶，绿豆淀粉的合成与积累主要由AGPase控制。

Abstract:

To uncover the relationship between the accumulation of starch components and starch metabolism during mung bean grain filling, four mung bean cultivars, ‘Lvfeng 2', ‘Anlv 7', ‘Ankang' and ‘Ji0816Mao-3', were used in the study. The accumulation and changes of amylose, amylopectin and total starch as well as the changes of enzyme activities related to starch metabolism during the grain formation of mung bean after flowering were measured. The starch accumulation process was fitted by Logistic equation and the correlation was analyzed. The results showed that the accumulation of amylose, amylopectin and total starch increased continuously during the process of mung bean grain formation. The starch synthase AGPase, GBSS, SSS and SBE of four mung bean varieties showed a trend of increasing at first and then decreasing at the grain-filling stage. The dynamics of starch accumulation in the seeds of all cultivars can be fitted by Logistic equation. The maximum starch accumulation rate of ‘Anlv 7' and ‘Ji0816 Mao-3' appeared in 8-11 d after anthesis, while the maximum filling rate of ‘Lvfeng 2' and ‘Ankang' appeared in 15-18 d after anthesis. There was an extreme significant positive correlation between AGPase enzyme activity and starch accumulation rate. In conclusion, AGPase is the key enzyme of mung bean starch synthesis and the accumulation of total starch in mung bean is mainly regulated by AGPase.