Improvement PTGMS To Rice Blast Resistance By Molecular Marker-Assisted Selection And Anther Culture

Rice is one of the most important crops in the world, as staple food of one third of the people. Rice blast, caused by the fungus Magnaporthe griseais, is one of the most destructive diseases, and makes much loss to rice production. R6, a broad-spectrum blast resistance gene, was introduced into Y58S and Guangzhan 63 S by the combination of molecular marker-assisted selection and backcrosses from donor 194-3, obtained BC3F1 and BC3F2 population. Selected the fertile and half of sterile plants, which with the R6 genes for anther culture, and generated doubled haploid (DH) lines. This paper tried the method for improvement the blast resistance of two-line photo-thermo sensitive genic male sterile lines by anther culture and MAS. The results are as follows:1. Four different culture mediums were made up by changing the proportion of hormones. The results showed that culture medium Y3 was most suitable for the anther culture in the background of Y58S, and the ratio of callus induction was 15.08%; the ratio of green plant was 2.89%. But, Y2 was most suitable for the anther culture in the background of Guangzhan 63S, and the ratio of callus induction was 12.25%; the ratio of green plant was 2.62%. After KT was supplemented into the callus induction medium, the ratio of browning during the early culture period was increased significantly. Although anther browning favored microspore in development and vigor, caused the ability of pollen callus induction reduce, it was not the key factor2. In 2009, three DH lines, YLH1, YLH3 and YLH7 which had R6, were obtained by anther culture and molecular marker-assisted selection. It showed that the resistance to leaf blast and neck blast of the three DH lines more significant increase than that of Y58S under natural field condition. YLH1 showed sterility degree was 100% in natural field in Wuhan and Yuanan from June to September, and YLH3 and YLH7 were fertile. The resulted provide at the background of y58, R6 performed significant increasing in blast resistance.3. Examined agronomic characters for the hybrid F1, derived from crossing YLHlto 008, 009-1,009-2,011,012 and 9311, It was showed these crosses compared with Y Liang you 1 hao (CK) ahead heading for about 9 days. The difference in agronomic characters between YLH1/011 and YLH/9311 to Y Liangyou 1 hao (CK) was not obvious. The tiller per plant, spikelets per panicle and yield of YLH1/9311 was superior to CK. The spikelets per panicle and kernel weight of YLH1/011 was superior to CK.4. In 2010, obtained five DH line with R6, in which YHP2, YHP4, YHP6 were derived from Y58S genetic background materials, and YHP10, YHP11 were derived from Guangzhan 63 S genetic background materials. It showed that YHP4 and YHP6 were fertile, YHP2 was half of sterile, YHP10 and YHP11 were sterile under Hainan ecological conditions in winter.