Relationship between endosperm cell proliferation and seed formation in maize of different types | 不同类型玉米品种籽粒胚乳细胞增殖与籽粒建成的关系

Chinese. 研究不同类型玉米品种籽粒胚乳细胞增殖与籽粒充实期相关性状的关系。以紧凑型玉米品种(先玉335和郑单958)和平展型玉米品种(长城799和农大364)为试验材料，于授粉后3，5，7，10，15，20，25，30，35，40，45，50，55，60 d取果穗中部籽粒，观测胚乳细胞数目、单粒质量、灌浆速率、淀粉含量、籽粒淀粉磷酸化酶和蔗糖转化酶活性等指标的变化动态，并分析不同玉米品种籽粒胚乳细胞增殖动态与籽粒灌浆期相关生理指标的关系。随着灌浆期的延长，不同玉米品种籽粒胚乳细胞数、单粒质量、淀粉含量均呈“S”型曲线增长，籽粒胚乳细胞数在授粉后20 d基本稳定。胚乳细胞数与单粒质量、淀粉含量和灌浆速率均呈极显著正相关；籽粒充实期的生理状态影响着籽粒灌浆，淀粉磷酸化酶和蔗糖转化酶活性在灌浆期呈现单峰曲线，但峰值出现时间因品种而异，紧凑型玉米酶活性最高点出现时间要晚于平展型玉米；籽粒胚乳细胞数与这两种酶活性均呈显著相关。玉米籽粒中胚乳细胞数与胚乳细胞的充实状态、籽粒单粒质量、灌浆速率、淀粉含量、淀粉磷酸化酶蔗糖转化酶活性均呈显著正相关；要提高玉米产量，应在灌浆前期提高胚乳细胞增殖速率和灌浆速率，保证光合产物快速充分地运送到籽粒中去，使籽粒淀粉积累达到最佳状态，进而达到高产。

English. The proliferation process of endosperm cell and its relationship with the correlative properties of grain in filling stage were studied. The upright maize varieties Xianyu 335 and Zhengdan 958 and the common maize varieties Changcheng 799 and Nongda 364 were chosen as the experiment material. Central kernels were collected after the pollination stage, endosperm cell number, kernel weight, filling rate, starch content, starch phosphorylase and invertase were determined, and the relationship was analysed. The endosperm cell, grain weight and starch content kept increasing in the entire grain-filling period and the increase appeared like an “S” shape. The endosperm cell number of corn grain was determined on the 20th day after pollination. The endosperm cell number had significantly positive correlation with grain weight, starch content and the filling rate of kernels. The filling rate of kernels was evidently affected by physiological activity of kernels. The activities of invertase and starch phosphorylase appeared a single peak during the filling period, and the peak in upright maize occurred later than the common maize varieties. The endosperm cell had significantly positive correlation with the activities of invertase and starch phosphorylase. The endosperm cell number had significantly positive correlation with the kernel weight, filling rate, starch content, starch phosphorylase and invertase. In order to improve high-super yield, we must enhance the rate of endosperm cell proliferation and the filling before the filling period, and ensure the transportation of photosynthetic production to kernels quickly and repletely.