糯玉米颖果的发育及营养品质分析

Analysis on Caryopsis Development and Nutrient Quality of Waxy Corn

为明确糯玉米颖果的发育规律,采用常规测定方法研究糯玉米颖果的鲜重、干重变化及其淀粉、蛋白质、可溶性糖、脂肪的积累动态,借助扫描电镜观察淀粉粒的形态。鲜食糯玉米最适宜的采收期为授粉后25～30天;颖果中的淀粉含量前期增加较快,授粉20天后增加缓慢;蛋白质含量先急剧降低后缓慢增加;可溶性糖含量先升高后降低;脂肪含量总体上呈上升趋势。籽粒鲜重与淀粉含量和蛋白质含量分别呈极显著正相关(r=0.915**)和负相关(r=-0.961**),淀粉含量与蛋白质含量呈极显著负相关(r=-0.985**)。角质胚乳淀粉粒排列紧密,积压呈"足球状";粉质胚乳淀粉粒排列疏松,呈多面体状。

The caryopsis development in waxy corn was studied. Waxy corn was harvested at 25-30 days after pollination suitably. Starch content increased rapidly at early period and slowly from 20 days after pollination. Protein content decreased rapidly and then increased slowly. Soluble sugar content increased and then decreased. Fat content showed a rise tendency as a whole. Fresh weight was positively correlated to starch content （r=0.915^＊＊） and negatively correlated to protein content （r=-0.961^＊＊）. Starch content was negatively correlated to protein content（r=-0.985^＊＊）. Starch granule of cutin endosperm arranged tightly and showed a ＂football＂ shape. Starch granule of powder endosperm arranged loosely and showed a polyhedron shape.