Analysis Of Genetic Diversity In Brassica Juncea Czern. Et Coss

In this research, botany character, the agronomic characters, the inbred line relation as well as the SSR analysis of 34 Brassica juncea varieties, which are from different countries, different area and different background were studied. The analysis of Brassica juncea mutual blood relationship attempts to carry on the appraisal to our country Brassica juncea heredity diversity, excavates the special germplasm and the advantageous gene, for well preserve and the use of Brassica juncea germplasm resources, and provides the theory basis for the improvement of Brassica napus variety.1. Through conducting the research on growth characteristic and the botany shape characteristic of the tested variety, the results indicated that: the difference of different varieties, region, and subspecies is significant to the growth characteristic as well as the botany shape aspect, the concrete manifestation is in the period of duration length difference, a longer growing period of the material is high-strain-Chuan Huang, yellow hot mustard, B.juncea, Xiahe Port pin, Gansu wild rape, for 114 days; a shorter growing period Jingtai yellow material rapeseed, rapeseed Jingyuan Huangâ…¡, for 102 days. There were also large differences in flowering period, flowering period is the longest Brown mustard, for 50 days; flowering as soon as possible is Longxi Tong'an gold mustard for 30 days.while for the botany shape characteristic mainly displays in the leaf, the stem, flower's color, the character, seed's color and character, especially between the home and the overseas variety, also between the big leaf mustard subspecies and the small leaf mustard material.2. The analysis of agronomic traits of the tested materials discovered that there is remarkable difference among different variety and different subspecies, such as plant height branch spot, branch number, 1000-seed-weight, etc. The relevant analysis results showed that, height, branch number, the number of available pods, 1000-seed-weight display certain relevance with yield per plant.3. In this paper, the most of Brassica juncea are self-compatible, but Brassica juncea self-compatibility varied within a great range 0.25-9.73, This variation existed not only among the species but among sub-species. evaluated by the self-compatible indexes, among 34 experiment materials, two varieties are self-incompatible(01.00), eighteen varieties are high self-compatible (SC>4.00).4. 89 pairs of SSR makers were selected to screen on 34 Brassica juncea. There are 8 pairs of SSR markers with specific band and good polymorphism. Total 23 loci were detected. The cluster analysis showed that all the varieties were divided into 3 groups, each group separate into certain small subgroups, displays the rich hereditary basis and the multiplicity. Except Brown mustard alone clustered into one group and was inconsistent with the agronomic traits, other materials conform to their outside appearance.