《植物生理学报》 2015, 51(1): 88-92

糯玉米胚乳淀粉粒粒度分布形成的酶学机理

伊祖涛¹, 张海艳^1,2,*

¹青岛农业大学农学与植物保护学院/山东省旱作农业技术重点实验室, 山东青岛266109; ²山东省小麦玉米周年高产高效生产协同创新中心, 山东泰安271018

通信作者：张海艳；E-mail: hyzhang608@126.com；Tel: 0532-86080447

摘　要：

以7个糯玉米品种为材料, 测定其籽粒发育过程中淀粉粒粒度分布及淀粉合成相关酶活性的变化, 分析两者之间的关系。结果表明, 随着籽粒发育, 糯玉米淀粉粒平均粒径逐渐增大, 可溶性淀粉合成酶(SSS)和淀粉分支酶(SBE)活性呈单峰曲线变化。籽粒发育前期, 小淀粉粒(≤7.4 μm)所占体积较大; 随着籽粒发育, 小淀粉粒所占体积减少, 大淀粉粒(>7.4 μm)所占体积增多; 籽粒发育后期, 大淀粉粒所占体积较大。相关分析表明, SSS和SBE活性与大淀粉粒体积增大速率和平均粒径增大速率均呈显著或极显著正相关。因此, SSS和SBE是影响糯玉米胚乳淀粉粒粒度分布形成的主要酶, SSS和SBE活性越高, 淀粉粒平均粒径越大, 大淀粉粒所占体积越多。

关键词：糯玉米; 淀粉粒粒径; 粒度分布; SSS; SBE

收稿：2014-11-06   修定：2015-01-04

资助：国家自然科学基金(31101100)、山东省科技发展计划(2014GNC111001)、作物生物学国家重点实验室开放课题(2013KF05)和山东省旱地作物水分高效利用科研创新团队。

Enzyme Mechanism of Starch Granule Size Distribution Formation in Waxy Corn Endosperm

YI Zu-Tao¹, ZHANG Hai-Yan^1,2,*

¹College of Agronomy and Plant Protection, Qingdao Agricultural University/Shandong Key Laboratory of Dry Farming Technique, Qingdao, Shandong 266109, China; ²Cooperative Innovation Center of Efficient Production with High Annual Yield of Wheat and Corn, Tai’an, Shandong 271018, China

Corresponding author: ZHANG Hai-Yan; E-mail: hyzhang608@126.com; Tel: 0532-86080447

Abstract:

In this study, seven varieties of waxy corn (Zea mays var. sinensis) were used to determine starch granule size distribution and starch synthetic enzyme activity and analyze their correlation. The results indicated that with kernel development, mean diameter of starch granule increased, and soluble starch synthase (SSS) and starch-branching enzyme (SBE) activities showed single peak curve. During early period of kernel development, the volume percentage of small starch granule (≤7.4 μm) was large. Then, the volume percentages of small and large starch granules decreased and increased, respectively. During late period, the volume percentage of large starch granule (>7.4 μm) was large. Correlation analysis indicated that SSS and SBE activities were positively (highly) significantly correlated with the increasing percentages of large starch granule volume and mean diameter. Therefore, SSS and SBE are the key enzymes to affect starch granule size distribution formation of waxy corn. The higher SSS and SBE activities are, the larger mean diameter and volume percentage of large starch granule are.

Key words: waxy corn; starch granule diameter; size distribution; SSS; SBE