Studies On Rapid Indentification Method Of The Self-Incompatibility Of Cabbage

There are lots of advantages to breed by hybrid vigor ,for example, disease resistance, freezing resistance, prolific production .regular mature .Using self-incompable lines to produce crossing breed is an necessary method for Cruciferae vegetables, however, rapid identification of self-incompatibility is a basic step. It is important to accelebrate pace of breeding process. In the experiment, 12 individual plants of each system among three systems of cabbage inbred lines which had different index of affinity were selected as experimential materials. Self-incompatibility was identified respectively by three methods-the method of determinating the index of affinity; the method of observing the number of pollen tubes of stigma after pollination by fluorescence microscopy, and the method of identifying the specific band in polycrylamide gel isoelectric focusing. Besides, culture medium of pollen germination was screened, too. The main results were as follows:It can be used to identify the high self-incompatible lines, partial self-incompatible lines and self-compatible lines by observing the number of the pollen tubes of stigma in 24 hours after flower-stage pollenation. There were less 5 pollen tubes passing throught individul-plant stigma of high self-incompatible line, less 10 pollen tubes passing throught individul-plant stigma of partial self-incompatible line, and more 15 pollen tubes passing throught individul-plant stigma of partial self-compatible line in 24 hours of flower-stage pollination. The method is easy applied for rapid identifying the self-incompatibility of cabbage.The result on indentification method of self-incompatibility by observing the bands of polycrylamide gel isoelectric focusing showed: polycrylamide gel isoelectric focusing can be used exactly to indenfy high self-incompatible lines of cabbage. Specific bands which were speculated to be the S-locus specific glycoproteins at PI8.5-9.1 were observed for the individul-plant stigma of the high self-incompatible line .The best composition of Brassica oleracea pollen germinating culture medium: the content of sugar, boric acid, agar is respectively 16.62%, 126.04ppm, 1%.Index of affinity had prominent positive correlation with the number of pollen tubes, however had not prominent positive correlation with the specific bands for the individul-plant stigmas of the self-compatible line.The studies on index of affinity for different methods of pollenation showed: the different positions of the flowering branch caused different index of affinity . Generally, the fruiting index of self-crossing was low and stable at the middle and lower branchs of plant and high at the upper branchs. Besides, it was affected by the flowering age. The index was high during the bud stage of the flowering, the highest index appeared in 1~2days beforeflowering.Afferwards, it reduced gradually in the flower stage desclinning.