Fine Mapping And Candidate Regions Determinen Of BnMs4Gen Can Restore The Fertility Of Recessive Male-Steril In Brassica Napus

Chen Fengxiang reported that, the fertility of9012AB is composed by two pairs of recessive genes overlap (Bnms3ms3, Bnms4ms4) and a epistatic inhibition gene (Bnrfrf), when epistatic gene homozygous recessive (Bnrfrf) can inhibit the sterility controlled by Bnms3ms3ms4ms4, then the plants being fertile.736512A and9012A has the same genetic patterns.Zu Feng used the share molecular markers and backcross inbred laboratory, and linkage disequilibrium analysis of perceived control736512AB fertility BnMs4and Bnrf are likely to be multiple alleles. Dong Faming did genetic analysis using9012AB and its temporary maintainer line T45to hybrid and conventional varieties test cross with sources of different material, proposed the new genetic model of9012AB. The two articles draw a common conclusion, the fertility of9012AB actually controlled by2nuclear genes (BnMs3and Bnrf), the BnMs3locus has2alleles, fertility gene BnMs3and male sterile gene Bnms3, and the Bnrf locus has3alleles, fertile gene BnMs, sterile gene Bnms and recessive epistatic gene Bnrf. What is close linkage gene or multiple allele’s genes still need further research. To further elucidate the relationships between these genes, fine mapping and candidate regions determinen of BnMs4and Bnrf is very necessary. This experiment use the736512AB as material, adopt the map-based cloning method, using a variety of development molecular markers coming from Brassica napus, fine mapping and candidate regions identified of the recessive genic male sterile restoring gene BnMs4, the main results and conclusions are as follows:1) Predecessors has identified the BnMs4to a genetic distance of1.0cM and2.4cM by two sides.On the basis of these reseach I develop and design a number of molecular markers, such as CL14, CL15, CL16, H3-2, DD29,34BJ4, they are more close to BnMs4,and locked it to0.20cM and0.1OcM by ssr103YH and CL14.2) Using an improved group from736512AB (including6060individuals), position the BnMs4to a genetic distance of.1.57cM and0.1OcM3) Using a group coming from years of hybrid by near isogonics line of736512AB (including1993individuals), position the BnMs4to a genetic distance of.0.20cM and0.15cM4) Comparing sequencing found that the Bnms4has a6bp deletion mutation in a SSR site, and there are many differences between BnMs4and Bnms4in the level of cDNA 5) Screening of a BAC library for shotgun sequencing gets some partial information of genes near to the BnMs4.5) Use the closest molecular markers by two sides locked the gene to67k range and predict five candidate genes.