Identification Of The Derivative Progenies Derived From Cabbage-Chinese Cabbage Allotriploid And Cabbage

In this study, the BC₁ and BC₂ plants derived from the progenies of reciprocal crosses between cabbage-Chinese cabbage allotriploid （CCA,2n=3x=28） and diploid cabbage（CC,2n=2x=18） and their selfing progenies were used as studying materials. Through cytological and SSR analysis, two primary trisomics of cabbage, two tetrasomics of cabbage, one euploid translocation line of cabbage-Chinese cabbage and two aneuploid translocation lines of cabbage-Chinese cabbage were obtained. This study will provide the basic testing materials in genetics and breeding of cabbage and will help to establish the translocation lines of Brassica .The results are listed as follows:1. Through cytological and SSR analysis, two primary trisomics of cabbage,two tetrasomics of cabbage were obtained from the BC₁ and BC₂ plants derived from the progenies of cabbage-Chinese cabbage allotriploid backcrossing with and to diploid cabbage, and their selfing progenies plants. And the obtained primary trisomics of cabbage were primary trisomic-1 and primary trisomic-8 of cabbage, and their corresponding tetrasomics.2. Through identifying the chromosome number of the selfing and backcrossing progenies of the primary trisomic-1,trisomic-8 of cabbage, the transfer rates of female and male gametes of extra-chromosome were clarified.The female gamete transmission rates of extra-chromosome are 16.11% and 34.74%, respectively; the male of gamete transmission extra-chromosome rates were 13.89% and 6.17% respectively. The female gamete transmission rates of extra-chromosome are higher than that of male gamete.3. The meiosis behavior of PMCs in the primary trisomics of cabbage tetrasomics of cabbage was observed. The results indicated that the chromosome configurations at diakinesis for the primary trisomic of cabbage plants are mainly showed 8Ⅱ+1Ⅲ, extra chromosome exist in trivalent chromosome. The chromosome configurations at anaphaseⅠare mainly showed 10-9, and chromosomes are mainly distributed with 10-9-10-9 at anaphaseⅡ. For the tetrasomic of cabbage plants, the chromosome configurations at diakinesis are mainly showed 10Ⅱ. The chromosome configurations at anaphaseⅠare mainly showed 10-10,and chromosomes are mainly distributed with 10-10-10-10 at anaphaseⅡ.4. The phenotypic analysis indicated that there are differences in characteristics of plant growth, plant height, bolting, leaf shape, leaf color, leaf Characteristics and flower organ when compared the diploid cabbage plants. Especially, the tetrasomic-8 of cabbage plant grows weakly, is adhered of less waxes on leaf surfase than its parent, and its stamen was abnormal. The pollen amounts, pollen uniformity and pollen viability in tetrasomic in tetrasomic are significantly lower than in diploid cabbage.5. Through cytological and Indel marker analysis, one euploid translocation line of cabbage-Chinese cabbage and two aneuploid translocation lines of cabbage-Chinese cabbage were obtained from these the BC₁, derived from the progenies of cabbage-Chinese cabbage allotriploid backcrossing with and to diploid cabbage, and their selfing progenies plants. It showed that the introduced chromosome segment of the translation lines come from linkage group 07 in Chinese-cabbage. And the introduced chromosome segments of aneuploid translation lines come from linkage group 02 in Chinese-cabbage.6. The observation of PMCs meiosis behavior of cabbage-Chinese cabbage aneuploid translocation lines plant showed that: there are many chromosome separation behaviors with unstable genetics.7. The phenotypic analysis of cabbage-Chinese cabbage aneuploid translocation lines indicated that the plant height of aneuploid translocation lines is short,the branching ability is weak, the waxes on leafy surface are more,and the pollen amounts, pollen uniformity and pollen viability are decreased significantly when compared with their parents. And budding and flowering time are seven days later than in parent.