摘要
根据小麦成熟期籽粒淀粉组分的差异 ,用聚类分析的方法 ,将籽粒总淀粉含量相近、直链淀粉和支链淀粉含量存在差异的 9个小麦品种分为 3组 :低直链淀粉组、中直链淀粉组和高直链淀粉组。研究籽粒灌浆过程中 ,直链淀粉与支链淀粉比值 (直 /支比值 )的变化动态、淀粉合成相关酶活性的变化动态及其与淀粉组分积累的关系。结果表明 :高直链淀粉组的直 /支比值在花后 2 8d和 35d显著高于低直链淀粉组和中直链淀粉组 ,说明不同小麦品种直 /支比值的差异是灌浆中后期直链淀粉与支链淀粉积累速率的不同所致。在灌浆期 ,籽粒中淀粉粒结合淀粉合成酶 (GBSS)活性较低 ,同时灌浆中后期 ,腺苷二磷酸葡萄糖焦磷酸化酶 (ADPGPPase)、尿苷二磷酸葡萄糖焦磷酸化酶 (UDPGPPase)活性较低的品种(低直链淀粉组 ) ,籽粒直链淀粉含量较低。籽粒中较高的可溶性淀粉合成酶 (SSS)活性 ,在灌浆前期有利于直链淀粉和支链淀粉的积累 ,而在灌浆后期 ,则有利于支链淀粉的积累 ,不利于直链淀粉的积累。
Nine wheat cultivars with similar total starch content and different amylose and amylopectin content in mature stage were classified into three groups: low amylose, medium amylose and high amylose. The dynamic changes in ratio of amylose to amylopectin, and the activity changes of four enzymes in relation to starch biosynthesis and their relationships to the amylose and amylopectin accumulated during grain filling period were examined. The results showed that the ratio of amylose and amylopectin of wheat cultivars from group of high amylose was significantly higher than those of the other groups in the 28 d and 35 d after anthesis, and that the different ratio of amylose to amylopectin of variant wheat cultivars was caused by different amylose and amylopectin accumulation rate during middle and late stages of grain filling. Wheat cultivars, from group of low amylose, also with low granule bounded starch synthetase (GBSS) activity during filling stage and with low adenosine diphosphate glucose pyrophosphorylase (ADPGPPase) and uridinediphosphate glucose pyrophosphorylase (UDPGPPase) activity during middle stage and late stage of filling, produced less amylose in grains. High soluble starch synthetase (SSS) activity enhanced accumulation of amylose and amylopectin in the early stage of filling, but it would accelerate amylopectin accumulation and decelerate amylose accumulation in the late stage of filling.
出处
《作物学报》
CAS
CSCD
北大核心
2004年第6期525-530,共6页
Acta Agronomica Sinica
基金
国家自然科学基金项目 ( 3 9970 42 5 )
科技部生态农业技术体系研究与示范项目( 2 0 0 2BA5 16A12 )
