The Research On The Aspartic Proteinase And Anther Tapetum In Physiological Male Sterility Wheat

With the widely use of heterosis helps improve the production and quantity of wheat. Chemically-induced by SQ-1 male sterility(CIMS) system in wheat, one type of the male sterility that is used in hybrid wheat(Triticum aestivum. L.), now is widely used due to the fact that CHA allows the production with a great quantity of parental combinations. SQ-1 as a new type of wheat gametocide can lead to male complete sterility and without any side effects on the stamens of wheat. Thus, SQ-1 has been applied to produce hybrid seeds on a large scale in China. However, the mechanism of inducing wheat male sterility by SQ-1 is not very clear now. This experiment aims at exploring the relationship between tapetum degradation in anther and pollen abortion in CMS of wheat. In this article, based on the results about tapetum degradation that have been done in our lab, and using physiologically male sterility induced by chemical hybridizing agent SQ-1 and corresponding normal lines of complete fertility as experimental materials in wheat, we did follow experiments. The ultrastructure of tapetum was analyzed via transmission electron microscope, the APs expression was analyzed through Real-time PCR. And the activity of aspartic proteinase was analyzed by SDS-Gelatin-Page. Now, here are the results.(1)The tapetum of anther was degraded in two materials and in physiological male sterile lines, it pre-degraded comparing with normal one at mononuclear stage. At tetrad stage there was no degradation in both two materials and less organelle was obsezved in physiological male sterile lines. At the early mononuclear stage the tapetum degraded in these two materials, and in physiological male sterile lines the degradation was much worse. When come to the late mononuclear stage the tapetum in normal wheat continued to degrade and the one in physiological wheat degradates completely.(2) By comparison with normal tetrad and the performance of fluorescence Real-time PCR,the research obtained relative expression of APs gene from tetrad to trinucleate stage of anther. The expression of one APs gene was firstly up regulated and then decreased reaching its highest expressions at mononuclear stage and the expression of APs in physiological male sterile lines was higher than the expression in normal wheat.(3) The activity of aspartic proteinase analyzed showed that the expression of APs activity increased at first and then dropped, reaching its highest point at binucleate stage. On the other hand the activity of APs in physiological male sterile lines was much higher than it was in normal wheat in all stages.