| In the improvement on Brassica, the heredity variability of interspecies has been effectively utilized by the breeders , however, it is imperative to enlarge the gene pool. Rocketsalad(E. sativa Mill) has strong adaptability, and has many good character such as drought-resistance, enduring infertility, disease-resistance, enduring salt-aphis and so on. In order to achieve the good genetic transfer between the two different race , the writer of this paper has carried out a systematic research into the compatibility, the recognition of reaction between stigma and pollen, the hybrid ovary and embryo culture and the identification of genuine and sham hybridization seeds of Brassica and Rocketsalad. The results show:(1) High incompatibility is showed in the crossing of Brassica with Eruca sativa Mill. Adopting the conventional sexual hybridization means between Brassica and Rocketsalad in reciprocal, the compatibility is the highest in male sterility material, which indicates the sterile cytoplasm effect of the distant hybridization compatibility in rapeseed male sterility, followed by Brassica napus and Rocketsalad. The lowest being in other Brassica and Rocketsalad. Those results show the high or low of hybrid compatibility has very close relationship with the parents' genotype and the kinship in the distant hybridization. Utilizing the chemical substances that can overcome selfhybridization incompatibility to handle stigma is helpful in enhancing crossing compatibility of two parents but only to a very limited extent. So only when we depend on the contemporary bio-technique can the good genetic transference be achieved between the two different race.( 2 ) By observing the two Rocketsalad pollen attachment and germination to stigmas of the five rapeseeds and the recognition reaction between the pollen tube and the stigma in the fluorescent light microscope, the writer attempts to find the obstruction preceding fertilization in distant-crossing. Results reveal that with the rapeseed adoption of the pollen, the pollen delays adhering to the stigma and germinating, it' s hard for the pollen tube to extend, thus such intergenus phenomena as distorting and swelling arise. Moreover, the mamma cell produces such intense callus reaction that it prevents the unusual source pollen tube from going to the stigma. Owing to parents' native genotype differences, discrimination reaction differs considerably. The sequence from the highest to the lowest in sticking velocity is 681A , 571 lodging-resistance, Xiangyou 15, 742 Te , Xinjiang uncultivated rape.( 3 ) During the ovary culture, the ovary growth amount is the largest, the amount of embryos and seedlings is the most in the treatments of ovaries excised 6 ~8 days after pollination . Relevantly, the average forming embryo amount and forming seedling amount per horn-fruit are the highest. By using the hormone culture medium of difference concentration and associations hormone, including non-hormone, to handle the material, the hybrid embryos of the Xiangyou 15 and Rocketsalad con be both obtained, and the association of 1.0 Mg/L NAA+0.5 Mg/L 6-BA has the best effect. When two kinds of hormones are employed separately, they can enhance forming embryo amount and forming seedling amount of the Xiangyou 15 and Rocketsalad. When two kinds of hormones are employed together, the growth hormone has an obvious accelerating effect on Xiang-You 15. The low concentration of cytokin has an accelerating effect on the growth hormone, however, the high concentration of cytokin has an inhibitive effect, and the more the concentration is, the more inhibitive effect there is, forexample, the result of 1.5 Mg/L NAA+2. 0 Mg/L 6-BA is the same as non-hormone.(4) During the embryo culture, the growth hormone and cytokin have obvious accelerating effect on its development, but the effect isn' t obvious while attached component (casein ) is employed alone, however, the effect is better when it is employed with growth hormone.(5) The ovary and embryo culture can both attain some forming seedling... |
