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Rice mutants mainly from natural mutation and artificial mutagenesis, natural mutation and artificial mutagenesis is to create new germplasm, breeding new varieties of important ways. In this paper, six copies of the genetic material of rice mutant analysis and gene mapping, where D77, D83, D86, D91 and ygl98 the yellow leaves mutations material obtained through the EMS mutagenesis; 802A is a natural mutation male sterile materials, indica strains Shuhui Shuhui 881 hybrid 527 and F8 groups found. The main findings are as follows: yellow green mutant D77, D83, D86 and D91 of the entire growth period showed yellow leaves, plant morphological and agronomic traits similar photosynthetic pigments little difference. And compared to the wild-type parental 10079, D77, D83, D86 and D91 of chlorophyll and carotenoid content were decreased by 47.1% and 40.4%; plant height, spike and grain weight average of the grains were reduced by an average of 6.7%, 8.9%, and 10.2%, leaf width increased by an average of 13.3%. TEM observation showed, D77 mutant chloroplast most irregular shape, some of the chloroplast was distorted shape, grana lamellae stacked pile decline in number of loosely arranged. Genetic analysis showed that, D77, D83, D86 and D91 mutant trait by one pair of recessive genes. Respectively D77 / Zhejiang Fu 802, D83 / Zhejiang Fu 802, D86 / Zhejiang Fu 802 and D91 / Zhejiang Fu 802 F2 mapping population of molecular markers for localization, the results show that, D77, D83, D86 and D91 were carried mutations located in the short arm of chromosome 2 near the SSR marker RM110, InDel mark Ch2-27 and Ch2-32, with an average genetic distance of 1.5 and 1.6 cM. D77, D83, D86 and D91 hybridized with each other, all the leaves F1 plants were similar with both parents, showing yellow leaves, it can be considered D77, D83, D86 and D91 mutant gene allelic relationship, a new rice yellow green mutant gene. Yellow green mutant ygl98 entire growth period also showed a yellow-green. Compared with the wild type, ygl98 mutant chlorophyll and carotenoid content were decreased by 45.3% and 45.6%, respectively, effective panicle and seed setting rate decreased by 14.4% and 10.7%, plant height reduction of 7.4%. TEM observation showed that, ygl98 mutant chloroplast irregular shape, there are many empty chloroplast vesicle-like structure, reducing the number of thylakoids per grana by only a handful of thylakoid stack stacked together. Genetic analysis showed that, ygl98 mutant trait by a recessive nuclear gene. Use (ygl98 / Zhefu 802) F2 mapping population as the mutated gene was located on the long arm of chromosome 3 between I3 and I4 InDel markers, genetic distances were 0.07 and 0.19 cM, the physical distance between two markers is approximately 44.2 kb, this area contains eight ask predicted genes. Genome sequence analysis, ygl98 mutant enzyme encoded magnesium ion chelating OsChlD Ch1D subunit gene coding region at nucleotide 1522 (located in exon 10), G mutation of nucleotide bases A, resulting coding Section 508 protein sequences of alanine (Ala) mutated to threonine (Thr). The gene has been reported in rice yellow leaves Chlorina-1 gene allele, but a clear distinction between mutant phenotype, Chlorina-1 mutant in 2 to 3 weeks seedlings began to appear yellow green, yellow green and the trait only in the seedling stage performance, and ygl98 mutants have shown throughout the growing period for the yellow leaves, which may be OsChlD genome sequence caused by different mutations. Anthers of male sterile mutant 802A thin, dry, cracking, milky white appearance, with typical abortive pollen mainly belonging to the ordinary types of male sterility. Meanwhile, the mutant also showed glume thinner, twisted, flag leaf shorter, narrower, internal volume, panicle panicle and other features. Our previous findings suggest that, 802A male sterility trait from one pair of recessive nuclear gene controls to 802A / Ⅱ-32B F2 and 802A/02428 F2 to locate groups using SSR markers for gene mapping, discovery RM3513, RM6266 with the sterility gene linkage between genetic distance of 0.6 cM and 3.9 cM. In order to locate the target gene, developed a new five polymorphisms have an affinity for the insertion / deletion (InDel) mark, namely S1, S2, S3, S4 and S5, genetic linkage mapping analysis showed that the mutated gene is located on S2 and S5 between genetic distance of 0.6 and 0.3 cM, and S3 and S4 with InDel markers in 167 F2 sterile plant were separated. S2 and S5 markers defining the mutant gene in a region of about 244K, the region contains AC147427, AC145383 and AL713930 other three BAC. And have so far been reported in rice male sterility gene comparison, that the 802A mutant gene is carried by a new rice recessive genic male sterility gene, tentatively named ms92 (t).
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