Analysis On Genetic, SSR Marker And Protein Expression Of Cold Hardiness In Winter Brassica Rapa

Winter rapeseed (Brassica campestris) has excellent cold hardiness, it is not only major oil crop, but it is winter and spring cover crop, and it causes great economic and ecological significance on agricultural production in the north areas.This study used two varieties of winter Brassica.Rapeseeds: super-cold Longyou6 and weaker-cold Tianyou8, obtained F₁ and F₂ generation through reciprocal cross. The two groups of F₂ generation were used for Basic research. Analyzed and research on genetic of cold hardiness in winter Brassica Rapa, SSR marker be relared to cold hardiness and protein expression of different cold hardiness varieties. The main results are as follows:1. Statistical separation ratio about the number of F₂ generation plants of Longyou6 and Tianyou8 by cold hardiness or not. The ratio of measurement values and the theoretical value used chi-square Suitability for testing, to checking separation ratio. The results showed that cold resistance of winter Brassica rapeseed was controlled by two the main genes, which expressed with R1 and R2. The two pairs of genes acted on the same characters, the effect was cumulative, and there was no recessive relationship between the allele. Separation ratio has deviation when weaker-cold varieties as female parent.Reciprocal cross ratio was different, it declared that the cold resistance heredity of winter Brassica rapeseed not only controlled by nuclear genes, but it connected with the cytoplasmic heredity.2. Using the primer of SSR molecular marker analysis of the 508 per plant of F₂ generation of Longyou6 and Tianyou8, and the results following: which totally got 7 molecular markers closely linked with cold hardiness Rf in winter Brassica rapa. Applying software of Mapdraw builds genetic map. 7 markers and linkage degree of cold hardiness from near to far were as follows: BRMS-050,Ol12-A04,BRMS-042-2,BRMS-036,Ra3-D02b,Na10-C06,Ra3-D04, Linkage distance was that: 4.09,5.83,9.49,12.73,12.96,16.88,24.61, Among them, the marks BRMS-050, Ol12-A04 was nearer to the cold hardiness gene Rf genes from the genetic distance, These marks can be used as reference of molecule marker assisted selection breeding in winter Brassica rapa.3. Analyzed on parental materials Longyou6 and Tianyou8 of winter rapeseed with two-dimensional electrophoresis of proteins (2-DE). When loading quantities were at 1000μg/IPG strips. Super cold varieties Longyou6 and weaker-cold varieties Tianyou8 were detected effective protein spots 1207 and 1053. Using Tianyou8 protein gel as the reference gel, Longyou6 in contrast, there were 76 differential protein spots, and in them, the expression of 49 protein level spots increased, 21 protein points decreased, increased 5 new protein spots and reduced 1 protein spots. The results showed that cold resistance of winter Brassica rapa Longyou6 related to the expression level of certain proteins, the varieties of strong cold hardiness had a high expression level of protein than weaker-cold varieties. Strong cold hardiness of Longyou6 also related to the specific protein expression.