Genetic Analysis And Gene Mapping Of Several Traits Related To Yield Of A Super-long Pod Line In The Re-synthesis Brassica Napus L.

The pod length, the number of seeds per pod and the 1000-seed weight are important economical traits, They play very important roles in the formation of yield. In this research, the P1, P2, F,, F2, B, and E2 generations of a resynthesis super-long pod "H218" and a natural pod "Westar" were constructed to study the inhertance of several traits related to yield (pod length, No. Of seeds per pod and 1000-seed weight), and the QTLs controlling three traits were located by using SSR markers. The main results were summarized as follows:1. Between two parents, the pod length and the 1000-seed weight had significant differences and the number of seeds per pod had no differences, so there was no need to study its inheritance. The value of F, with the pod length was intervient between the two parents and tended to "Westar" .while that of the 1000-seed weight exceeded the value of two parents.2. The genetic models of the pod length and the 1000-seed weight estimated were accorded with single addictive-dominant models and the main genetic effects were addictive effects.3. The results of estimation on genetic components and paramerters in the pod length and the 1000-seed weight indicated that the parents "Westar" playing predominance.4. The formula of Castle-Wright was used to calculate the gene numbers(K) controlling the two traits , the values of K were 13. 7588 and 3. 002 respectively, which meant that there were at least fourteen pairs of alleles affecting the length of pod and three pairs of alleles controlling the weight of 1000-seed.5. The broad heritability and the narrow heritability of the pod length, the number of seeds per pod and the 1000-seed weight were calculated. With the broad heritability , the value of the three traits were 0.6226,0.5158,0.2699; and with the narrow heritability, the value of the three traits were 0. 4384, 0. 325 and 0.1136.6. A SSR genetic map of Brassica napus L. was constructed with F> population It was devided into 19 linkage groups, including 76 markers and covering 1654. 5cM and everage distance was 21cM.7. Identification of QTLs for the pod length, the number of seeds per pod and the 1000-seed weight, 7 QTLs with mini effects were checked out. Among them there were 3 QTLs controlling pod length with 18.5%, 9%and 5.3% variation contribution ratio respectively. For the number of seeds per pod, 1 QTL was detected . The 1000-seed weight was controlled by 3 QTLs mapped on linkage group 1,12 and 17, and they could explain variations 2.5-12%.