| Rice appearance quality trait is mainly referred to grain length (GL), grain width (GW), ratio of length and width (L/W), chalkiness (CH), degree of white core (DWC), milling rice (MR) and transparence (TR). Appearance quality trait is one of the most important elements which affect commercial values directly. Credible results on genetic research of appearance trait will beneficial to breeding research. Recently, appearance trait research has made progress because of the improvement of molecular marker. We made attempt to obtain both genetic and Quantitive Traits locus (QTLs) information of appearance trait of elite rice Jiafuzhan by using SSR, and the result will be helpful to molecular marker- aided selection (MAS)A RIL population derived from Guangluai 4×Jiafuzhan was constructed, the number of RIL individuals is 435. The grain of F6 is the target of our research, and the result of phenotyping investigation showed that super-parents phenomena only existed in GW and WE. The average value of CH is 62.9%, which similar to Guangluai 4. All the appearance quality traits belong to quantitative traits. Correlation analysis among appearance traits indicates that GL and L/W, GW and L/W get very significantly correlation. r2 values are 0.7970**and-0.8033** respectively. Correlation between CH and GW is also very significantly positive, r2 value is 0.5445**. Correlations between WE and GL, WE and GW, WE and CH are all very significantly positive, r2 value is 0.5620**,0.5071**和0.5680** respectively. The result indicated that Jiafuzhan is high quality indica with relative high yield.Polymorphism analysis was conducted between GuangLuAi4 and Jiafuzhan, an elite indica rice variety, with 559 SSR markers. 201 SSR markers are polymorphic, with a ration of 35.95% and 157 SSR were chosen to construct linkage map. The genetic map consists of 127 SSR markers, with a total length 1015.7cM and an average distance of 8 cM. 35 QTLs were detected in total, 8 for GL, 6 for GW, 8 for L/W, 5 for CH and 8 for WE, which could explain the total variance 74.69%, 69.27,%, 73.56%, 47.68% and 49.62% respectively. Mapping result shows that there are 4 regions on linkage map including 25 QTLs, which are RM462-RM600 on chromosome 1, RM16-RM5475 on chromosome 3, RM169-RM440 on chromosome 5 and RM566-RM189 on chromosome 9 respectively. In these regions, the two flanks of RM411 on chromosome 3 confer the phenotypes of GL, GW, L/W and WE, which explain variance 31.72%, 13.34%, 18.25%, 13.81 % respectively and could increase GL, L/W effectively. RM289-RM598 on chromosome are the loci of GW, L/W, CH and WE that explain variance 16.13%, 6.19%, 27.35%, 13.20% and could decrease GW, CH at quite high degree. The genotype from Jiafuzhan could increase GL and L/W, but decrease CH. There are many QTLs in these two loci and could explain high variance relatively.In conclusion, we can take advantage of these two loci in rice breeding with aim to improve appearance quality trait of rice.
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