QTL Mapping Of Rice Protein Content In A Ril Population Of Rice And Analysis Of Eating Quality

Rice is the staple food of half of the world’s population. Rice endosperm mainly provides starch and protein.(The protein content of rice is generally around7%). Rice protein is a protein of high biological value, equivalent to that of eggs, milk. Rice protein is low antigenic protein, suitable for a wide range of food groups, especially for babies. Therefore, cultivating high protein content of rice varieties which provide excellent resources for rice food processing is the main direction of breeding.ml19(a variety with high protein)、Koshihikari (a variety with good eating quality) and recombinant inbred lines which were constructed by the cross between them were used to identify quantitative trait loci (QTLs) controlling rice protein content、studied protein accumulation in different period、analysised of eating quality of rice and screened high quality rice seed、used tightly linked markers to detect restoring gene and examined the coincidence rate between the field experimental results and molecular identification results,this result could be provided base for marker-assisted selection fertility restoring genes. The major results were as follows:(1)A whole genome linkage genetic map containing101markers was constructed by QTL IciMapping V3.2, with total length of823.59cM on whole12genomes. The average distance between makers is8.15cM. Four minor QTLs distributing on the four chromosomes were detected on chromosome1,6,8,10, respectively.(2)The accumulation curves of rice protein showed that the fastest accumulation period was between15～25d, appeared a stable period between25-30d, there was another period of rapid accumulation after30d. The gluten and gliadin of both of the two rice materials accumulated fast between20-25d. The difference is that m119(a variety with high protein) have another fast accumulation period between30-35d,while the protein accumulation curve of mzl l(a variety with low protein) leveled off after25d.(3)Using recombinant inbred lines materials analysised of eating quality of rice and screened high quality rice seed, The correlation analysis and stepwise regression analysis results showed that:protein content, amylose content, rate of the whole white rice had a greater influence on the eating quality of rice. Sensory evaluation results as follows:After repeated experiments, identified12rice strains that with good sensory integrated value,further analysised of the appearance characteristics and physical,chemical characteristics of the12rice strains, the results showed that:The protein content of strain354was as high as12.4%, The protein content of strain771was11.5%,the bud embryo rate of strain702was31.58%,these rice strains are all with high nutritional value and good eating quality, these should be as the key work of breeding, after further work needs to be applied to the production as soon as possible.(4) No significant difference was found between the molecular identification results by InDel-Rfla and the field experiment of38test cross materials. It could be used for marker-assisted selection for restorer gene Rf-1in rice.This study lay a foundation for rice germplasm resources innovation and new variety breeding...