The Research On Heterosis Utilization Of New-type B.napus.L

The 66 new-type of B.napus lines was created by using the method of interspecific cross between early mature B.napus varieties (039, E144) and especially early mature B.campestris Haoyou 11 of Tibetan Plateau by Academy of Agriculture and Forestry of Qinghai University. Main aspects studied include: (1) the deference between the new-type of B.napus lines and their female parents in agronomic characters and quality characters. (2) The restore lines and the maintainer lines in the new-type of B.napus lines. (3) The strong crosses and good parents in the combining ability analysis. In addition, the relation between the genetic distance and heterosis was studied in this paper. The main results are the following:(1)The growth period, yield traits, oil content, constituent of fatty acid and rape stem weevil resistance in these new-type of B.napus lines were studied in this paper. The result indicated that there were more excellent characters in the new-type of B.napus lines than that in the B.napus female parents: growth period less than 100 days in Xining, oleic acid content above 70%, saturated fatty acid content less than 5%, better yield traits, higher oil content, stronger resistance to rape stem weevil than that of the B.napus female parent. The new-type of B.napus lines will be provided for breeding of B.napus as new germplasm resource.(2) The 21 restore lines of Polima cms were obtained from the 66 new-type of B.napus lines, and the ratio is 31.82%; the 11 maintainer line were also fined, the ratio is 16.67. The results indicated that the frequency of restore gene and maintainer gene was higher in the new-type of B.napus lines.(3)In this experiment, the arrangement of the general combining ability effect in yield per plant of the three female parents is as follow: 770B>8B>860B, and the 10 male parents: 59>38>67 >49>52 >39>57 >1102>54>1160. In the special combining ability effect, the results indicated that the best cross in the yield per plant is 770B×59, and the next is 860B×38,8B×39,860B×59,860B×39,770B×39,8B×54,770B×57,8B×52,8B×1102. The general analysis of the general combining ability effect and special combining ability effect shows that the crosse 770B×59 was more ideal than others, and the yield per plant of the cross was 1st in the 30 crosses. Their ultra standard superiority was more than 50%.(4) The relation between quantitative characters genetic distance and heterosis index studied in this paper showed that there was no clear relation between them. From the result of cluster analysis, the interspecific cross between B.napus and B.campestris confirmed the effective method for expend genetic resource.