温度对两系杂交早稻灌浆成熟期籽粒淀粉合成代谢的影响

[目的]为了明确温度对两系杂交早稻灌浆成熟期籽粒淀粉合成代谢的影响。[方法]以两系杂交早稻株两优611和陆两优996为材料,研究了温度对两系杂交早稻株两优611和陆两优996灌浆期籽粒中直链淀粉积累、ADPG焦磷酸化酶（ADPG-PPase）和可溶性淀粉合成酶（SSS）活性的影响。[结果]高温条件下株两优611和株两优996灌浆前期籽粒中ADPG-PPase和SSS活性高,直链淀粉积累快,粒重增长快,持续时间短,抽穗10 d后ADPG-PPase和SSS活性迅速下降,抽穗16 d后淀粉积累趋于停止。适温条件下籽粒中AD-PG-PPase和SSS活性变化缓慢,抽穗13 d后达到其活性高峰值,直链淀粉积累慢,持续时间长,抽穗19 d后籽粒中仍有少量淀粉积累,粒重较高温条件下高。[结论]2个不同类型品种中适合作米粉原料的陆两优996在高温条件下籽粒中直链淀粉含量较适温条件下高,高温有助于高直链淀粉含量品种陆两优996籽粒直链淀粉的积累。

Effect of Temperature on Starch Biosynthetic Metabolism in Developing Grains of Tow-line Hybrid Early Rice during Grain-filling Stage

[Objective] The aim was to confirm the effect of temperature on starch biosynthetic metabolism in developing grains of two-line hybrid early rice.[Method] Tow-line hybrid early rice Zhuliangyou 611 and Luliangyou 996 were chosen as materials,the studies on the effects of temperature on amylose accumulation,the activities of ADPG-PPase and soluble starch synthase(SSS) in developing grains of Zhuliangyou 611 and Luliangyou 996 during grain-filling stage were carried out.[Result] The activities of ADPG-PPase and SSS,the speed of amylose accumulation and grain weight were high at the early stage of grain filling under high temperature condition,but the activities of ADPG-PPase and SSS in grains decreased quickly 10 days later after heading,and amylose accumulation was almost stopped 16 days later after heading.Under proper temperature condition,the activities of ADPG-PPase and SSS changed slowly,and the time of reaching peak of the 2 enzymes activities was 13 days later after heading.The amylose in grains was still accumulating slowly 19 days later after heading,and the weight of grain was higher than that under high temperature condition.[Conclusion] Under the high temperature condition,in 2 different rice varieties(Zhulianggyou 611 and Luliangyou 996),Luliangyou 996 had higher amylose content than that under proper temperature condition,high temperature was helpful to increase amylose content of Luliangyou 996.