花后不同时期高温处理下小麦籽粒的淀粉合成及相关酶基因表达

EFFECT OF HIGH TEMPERATURE DURING DIFFERENT GROWTH STAGE AFTER ANTHESIS ON STARCH SYNTHESIS AND RELATED ENZYME GENE EXPRESSION IN WHEAT GRAINS

为探讨弱筋小麦籽粒淀粉合成对花后高温的响应机制,以弱筋小麦扬麦15为试验材料,研究花后不同时期35℃高温处理对籽粒淀粉积累、淀粉合成酶(AGPase、GBSS、SSS、SBE)活性以及淀粉合成酶基因(AGPase1、GBSSI、SSSIII、SBEI)表达的影响。结果表明:小麦花后不同时期经35℃高温处理后,其籽粒淀粉积累量、淀粉合成酶活性以及淀粉合成酶基因相对表达量均呈现下降趋势,各处理下降的幅度均表现为:花后5～7d>花后10～12d>花后15～17d>花后20～22d>花后25～27d,且花后5～7d高温处理下降的幅度最大。4种淀粉合成酶基因中,GBSSI和GBSS对温度最为钝感,SSSIII和SSS对温度最为敏感。

The grain of Yangmail5 was employed to analysis the responses of starch synthase gene （ AGPasel, GBSSI, SSSIII, SBE1）expressions, the activities of starch synthases （AGPase, GBSS, SSS, SBE） , and starch accumulation of grain heat-treated at the level of 35℃ during different growth stage after anthesis. Results showed that the decrements of these parameters among different high-temperature treating periods followed the order of 5 -7 DAA 〉 10 -12 DAA 〉 15 -17 DAA 〉 20 -22 DAA 〉 25 - 27 DAA. The inhibitive effects were more significant under 5 -7 DAA. GBSSI and GBSS were insensitive to high temperatures, while SSSIII and SSS were sensitive to high temperatures.