The Molecular Breeding Of Aromatic Rice And The Preliminary Study The Molecular Mechanism Of The Formation Of Fragrance

Rice is major food crops in China, with the improvement of people live standards, the requirement of high-quality rice become more and more higher. Because of its unique aroma, fragrance rice occupies the important position in the international rice market, their price is as 2-3 times high as the normal rice. The international fragrance rice mainly comes from India and Thailand, so cultivating new fragrant rice with high-quality has an important value and significance. However, there are many deficiencies in conventional breeding, with rapid development of molecular biology, molecular marker can been utilize in breeding, This paper reviews latest development in fragrant rice breeding and molecular mechanism of flavor formation, meanwhile we breed a new fragrance rice variety that is fit for planting in shanghai area.In this paper, Betaine aldehyde dehydrogenase 2 (badh2/Badh2) of Aroma Rice W-Xiang 99075 and non-Aroma Rice 261S are cloned and analyzed by biology software Vector NTI, The results indicate that there are an obvious difference in the second intron, the fourth intron, seventh exon between two rice variety,according to this difference we designed a set of specific functional molecular marker M7 by permier primer 5.0.And then by functional molecular marker-assisted selection we cultivate the new two-line fragrant infertility 261S, using flavor rice W-Xiang 99075 as male parent and Non-Aroma 261 S as female parent.Meanwhile According to previous studies results, considering the Betaine aldehyde dehydrogenase 2 gene(badh2/Badh2) that directly related with rice fragrance, we also designed a pair of functional molecular marker M2. M2 applies to the fragrant rice genotype analysis and molecular marker-assisted breeding that have mutation in the second exon of badh2.On this basis, we analyzed shanghai region's main fragrant rice varieties by the two specific functional molecular markers M7,M2,the fragrance rice are divided into three categories:firstly the second exon mutation type; secondly seventh exon mutation type; thirdly other mutation type.By molecular biological methods we cloned and analyzed Aroma Rice Nanhai318 badh2 sequence, the results we could find no mutation in the coding or promoter regions that would be predicted to alter the BADH2 protein or its expression, while in the second and fourth introns occurred the same mutation as the other two type fragrance rice.This research obtained four types hybrid lines by Nanhai318 hybrided with four variety rices 08-07 fragrant rice (seventh exon),Su-hu-xiang qing (second exon),Nipponbare and Zhonghua respectively.Through the complementary test we explore the role of badh2 in the aroma formation of the Nanhai318 rice, at the same time we also built the complementary vector that lay the foundation for the further research of aroma formation mechanism.