优质蛋白玉米籽粒超微结构与品质性状的相关研究

以两个优质蛋白玉米（QPM）群体（T34QPMC3和陕综5号／O2C0）为试材，采用胚乳硬质度0，1，2，3，4五级分类法，对籽粒进行分析、观察．结果表时：胚乳硬质度越高，籽粒物理性状越好，蛋白质品质越差；硬质度越低，籽粒物理性状越差，蛋白质品质越好．在半硬质胚乳奥帕克-2玉米中，胚乳硬质度、籽粒密度的差异主要表现于胚乳内部组织，而胚乳边缘组织无差异．胚乳内部组织结构的疏密排布、淀粉粒形状、均匀住、角质化程度决定了籽粒物理性状的优劣；胚乳内部组织中基质蛋白形态、密度以及与淀粉粒结合紧密程度决定了优质蛋白玉米胚乳营养品质．

CORRELATION BETWEEN ULTRA-MICROSTRUCTURE AND NUTRITION QUALITY IN OPAQUE-2 MAIZE GRAINS

Two quality protein maize populations(T34QPMC3 and Shanzong 5/O2C0)and five classes(0, 1, 2, 3, 4)of endosperm hardness were used for ultra-microstructure study and chemical analysis of their grains. The results indicated that the harder the endosperm was, the better the physical characters were and the poorer the protein quality of grains was. Under the Opapue-2 background, the differences of grain denseness and endosperm hardness mainly expressed in internal endosperm tissue. Kernel physical characters were decided by cell distribution, shape, homogeneity and texture of starch grains in internal endosperm tissue. Nutrition quality was decided by the distribution, density and morphology of matrix protein, and the compacted degree between starch grains and matrix protein.