Study On The Transduction Of Gm6 Gene Rice Gall Midge Resistance By Using The Sanming Dominant Genic Male Sterile As The Vector

Rice gall midge(orseolia oryzae) is an important pest of rice in Asia, in China, mainly in the southern mountainous areas, hilly areas widespread, intermittent rampant. Cultivate rice gall midge resistant variety is the most cost-effective prevention and treatment approaches, however, the existing resistant varieties less, just only conventional rice varieties and some restorers, in the hybrid rice combinations are also the majority of two-line hybrid rice. Gm-6 is a rice gall midge resistance gene, it is the only one against four biotypes of gall midge in China gene. So, we try to designing a breeding methods on the basis research of the previous and the laboratory, by using the new rice germplasm of sanming dominant male sterile gene as the vector, and associate traditional breeding with modern molecular breeding to transduct the gall midge gene Gm-6 into the target parents using molecular marker-assisted selection(MAS). And, we hope to improve the target parents and find some new combinations with superior quality, high yiele and strong resistance by test-crossing. The main results in this experiment were as follows:1,In this experiment, Yuanfeng B was used as the recipient, Yuanfeng B with a high rate of milled rice,blast resistance and other excellent traits. The superior combinations of Yuanfeng 401, Yuanfeng 998, Yuanfeng Ming 86 by preparing of Yuanfeng A and Yuanfeng B, have been through Guangxi province, Zhangzhou City to the identification, have broad application prospects; Kangwenqingzhan with the Gm-6 as the donor; and the Sanming dominant genic male sterile with the specific traits as the vector. Many maintaining materials with Gm-6 gene were obtained by intercross, backcross, inbred and MAS. Of the materials, the improved Yuanfeng B which in BC5F2 generation has 5 lines homozygous and in BC6F2 generation has 5 lines homozygous. And they performed excel enough maintaining ability to Yuanfeng A. And the agronomic traits of improved Yuanfeng B are not significan-tly different from that of the original Yuanfeng B. All above sufficiently tested that experiment of improving Yuanfeng B was successful.2,Recevied a new breeding method by using sanming dominant genic male sterile as the vector in Gm-6 gene transduction. The sanming dominant genic male sterile was used as the female parent and with the target gene as the male parent were obtained the F1 hybrid plants; Molecular markers to detect by the F1 containing the target gene as male parent and the target plants as the male parent were obtained the rapprochement F1 hybrid plants; Molecular markers to detect by the rapprochement F1 progeny containing the target gene of the sanming dominant genic male sterile as female parents and the target parent as the male parents were backcrossed and obtained BC1; Followed by backcrossing to obtain the backcross BC4, BC5, BC6 et al; when backcrossed to BC5 or BC6 plants, were obtained the homozygous by molecular markers contained with target gene by selfing, So as to achieve improved recipient parent trait gene. This study has the advantage of ensuring the authenticity of the hybridization process and ensuring the accuracy and efficiency, and reducing the workload of breeding, to save time, labor, and efficient purpose.