Study On Synthetical Characters And RAPD Analysis Of Early-maturing Mutant In Brassica Napus

Brassica napus is one of the important oil crops in China. It is a good crop for rotation in theory,but late-maturing varieties usually influence the growth of other spring crops. In southern of China,cloudy and rainy weather also results in declining of yield and quality of rapes. Breeding and selection for early-maturing varieties are an important part of genetics and breeding of Brassica napus. Molecular marker techniques applicated in Brassica napus have been improved in recent years. Because of its advantages, RAPD(Random amplified polymorphic DNA),one of molecular marker techniques,is widely adopted by researchers. The major reasearch contents included:(1)To study the stability of premature characters and the influence of the different of growth period and sowing date to agronomic and quality characters of Brassica napus, varieties RG-8,FuYou No.4 and RG-8M were investigated. (2)This research used variety RG-8 and its early-maturing mutant(RG-8M) as the materials to study the difference between them at molecular level and screen the RAPD marker linked to the date of maturity by RAPD technology. The major results were shown as follows:(1)Through analysis of variance,the most growing characters of three materials had significant difference or extremely significant difference among sowing times,materials and the interaction of them. With the delay of sowing time,the whole growing period was shortened gradually. The growing period of RG-8M was significantly shorter than RG-8 and FuYou.No4.(2)Through analysis of variance,the most agronomic characters of three materials had significant difference or extremely significant difference among sowing times,materials and the interaction of them. Compared to yield per plant of FuYou.No4 which is local main cultivar,that of RG-8M was low,but it was higher than that of RG-8.It showed that RG-8M was more suitable for local production environment than RG-8.In FuZhou,when the sowing date was October 22,the yield was the highest.(3)Through analysis of variance,the most quality characters of three materials had significant difference or extremely significant difference among sowing times,materials and the interaction of them. The growing period of RG-8M was shortened,but some quality characters were better than that of RG-8 and FuYou.No4.When the sowing date was October 22,the quality of Brassica napus is best.(4)By RAPD technology,we prove the difference at molecular level between RG-8 and RG-8M.PCR results of 1 single primers which was named after S265 showed polymorphisms.the specific DNA fragment which is 686bp in length could only be amplified in RG-8.(5)Sequencing and alignment analysis of 686bp fragment revealed it was contact with the nucleotide sequence of Brassica rapa and sequence identity was 95%;the protein was contact with the amino acid sequence of Arabidopsis thaliana shikimate kinase-related and the sequence identity was 66%.