玉米杂种优势与杂交后胚中ATP酶活性和RNA酶活性及蛋白质含量的关系

通过对若干个玉米杂交及其亲本自交授粉后1天、3天、7天、10天胚中ATP酶活性、RNA酶活性及蛋白质变化的比较来探讨杂种优势产生的生化机理。结果表明,30个组合的玉米授粉后一天,有90%组合杂交胚中ATP酶活性超过双亲或母本自交胚中ATP酶活性。授粉后3天杂交胚中ATP酶活性多数低于双亲自交胚中的ATP酶活性,看来这一表现与自交授粉后胚中合子细胞分裂较迟缓有关。以上四个时期授粉后,杂交胚中RNA酶活性介于双亲之间或低于双亲,这可能与杂交胚中核酸分解的速度较慢有关。杂交胚中蛋白质含量变化不同时期各组合间表现不同,杂交后胚胎发育初期胚中蛋白质的变化不一定是总的数量的增加,而是某些蛋白质或酶的变化。

THE RELATIONSHIP BETWEEN MAIZE HETEROSIS AND ATPase AND RNAase ACTIVITIES, PROTEIN CONTENT IN THE EMBRYOS AFTER HYBRIDIZATION

Determinate changes of ATPase activities in certain combinations of maize hybrid and perential inbred embryos on the 1st, 3rd, 7th and 10th days to explore biochemical mechanism expressed by heterosis. The results obtained show that ATPase activities in hybrid embryos of 90% of 30 combinations on the 1st day after pollination are greater than those in parents or mother inbred embryos. ATPase activities in hybrid embryos of most combinations on the 3rd day after pollination are less than those in parents inbred embryos. And thus it can be seen that this expression may be related with slow division of zygote cells in the inbred embryos. For above 4 periods after pollination RNAase activities in hybrid embryos are between or less than those in parents embryos,which may be related with slower speed of nuclear acid resolutin. Changes of protein content in hybrid embryos seem to be different for different combinations. We believe that protein changes in the embryos after hybridization at early embryogeny stage are uncertain about the increase of total amounts of protein, maybe result from changes of protein and enzymes.