Allele Gene Type Of Rc Controlling Pericarp Color For Weedy Rice In China

Weedy rice (Oryza sativa f. Spontanea) and Asian cultivated rice (Oryza sativa L.) belong to the same genus Oryza AA genome type, does not exist reproductive disorders. Weedy rice has become the third malignant weed in some of the temperate countries. And compared to Barnyardgrass, Leptochloa, etc.,there is no effective weedy rice control measures and weedy rice herbicide. Weedy rice generally distinguished from cultivated rice with its characteristic red pericarp, so it is also called red rice. The most important regulator of red pericarp proanthocyanidins accumulate gene is Rc. Now it is lack of systematic research on the type of weedy rice Rc allele in China. Therefore our accurate identification of weedy rice red pericarp gene type, has important theoretical and practical significance in detection and monitoring for the spread of weedy rice.In this study, we investigated one of the hardest hit province by weedy rice:Jiangsu, then sequenced the whole 6429bp Rc gene of weedy rice and Ludao,Tangdao in 10 counties of Jiangsu, Sequences were integrate with existing166 Rc sequence in international databasesfor sequence analysis, the results showed that:(1) Jiangsu Province weedy rice types are red pericarp Rc wild-type allele, there is no one dominant homozygote sequenced sample carry 14bp deletion rc domestication allele characterized revertant type; (2) Jiangsu weedy rice Rc nucleotide diversity(Ï€=0.19) lower than the overall cultivated rice (Ï€=1.40) and cultivated rice japonica (Ï€= 1.40) and indica (Ï€= 2.25), also lower than the common wild rice (Ï€= 1.90), but higher than the U.S. weedy rice (Ï€= 0.07). Weedy rice has a H14 unique haplotype frequency (share 59.1%), can be distinguished from wild rice and cultivated rice, sui generis and stable inheritance; (3) Global rice gene sequence evolution of Rc network diagram and phylogenetic tree shows Jiangsu weedy rice are nearest to Wild Rice, with cultivated rice and red local cultivars distantly related, indicating Jiangsu weedy rice Re gene may be derived from wild rice. The Re gene of Lianyungang Ludao and Tangdao in Anhui evolution attributable to ordinary cultivated rice, their red pericarp has not any contact with weedy rice.Then, we croped 11 provinces, in total 156 species,2430 weedy rice samples of China in Nanjing Jiangpu experimental farm, extract leaf DNA and design identification mark RED4 across Rc gene 14bp deletion site in exon 7, and polyacrylamide gel electrophoresis, as well as Rc direct sequencing among 11 provinces of 33 homozygous dominant weedy rice to identify their Rc gene aelle genotype. Meanwhile selected Guangdong, Liaoning and Jiangsu three of the most serious occurrence of weedy rice provinces rc/rc homozygote recessive, Rc/Rc dominant homozygotes and Rc/rc heterozygotes of 10 rice samples for Rc gene length (6429bp) and flanking regions-2000kb,-1000kb,-200kb,800kb,2000kb location of five fragments sequenced directly, in which all Rc/rc heterozygous clones picked after five clones were sequenced to measure Rc homologous gene on chromosome haplotypes.The results showed that:(1)red pericarp weedy rice which cause harm in our country are Rc wild-type, there is no one dominant homozygote sequenced sample carry weedy rice domestication 14bp deletion allele characterized rc revertant type; (2) were tested 2430 weedy rice sample, white weedy rice and heterozygous respectively occupy 5.4% and 5.2% margin;(3) Jiangsu white weedy rice WRL-952 gene in Re 800kb and 2000kb position downstream of detected both weedy rice and homologous sequences; Guangdong white weedy rice wrl-2267 also in the upstream-1000kb has weedy rice detected homologous sequence, while heterozygous WRL-1725 and WRL-2257 by cloning and sequencing proved exist two locally cultivated rice and weedy rice homologous sequences, which shows that our white weedy rice (RED4 recessive homozygotes)comes from the local weedy rice and cultivated rice gene exchange.