Analysis Of Outcrossing Characteristics And The Genetic Potential Of New Cytoplasm Male Sterile Lines In Rice

This paper introduced the results of three aspect about the outcrossing characteristics and Genetic similarity and combining ability of 10 New CMS Lines, the potential use value of these New CMS Lines based on those results also have been evaluated. The main results showed:1、In the present research, some agronomic traits and outcrossing characters of 10 New CMS Lines(909A、910A、911A、912A、913A、914A、915A、916A、917A、918A) and 1 control material(D44 A) have been investigated, the results indicated that : every CMS Line’s sterile degree was 1, all of the CMS lines have complete sterility and stable. Each CMS line’ difference varied greatly in outcrossing characters, but in performance of agronomic traits, those materials were all general. 911A、915A、916A、917A had obvious blossom peak at 12:00, all the CMS lines had no fresh flowers open after 16:30. The range of spikelet opening time of 11 CMS lines was 1.45~3.62 h, the order of all materials in the sequence of decending was 914A、913A、915A、CK、918A、917A、916A、911A、912A、909A、910A; the range of opeing angle of spikelet was 18~29.06°, the order of all materials in the sequence of decending was CK、914A、915A、911A、918A、916A、917A、913A、912A、909A、910A. In the respect of stigma exserted rate and outcrossing setting rate, 914A、915A、918A were better than others, each of their stigma exserted rate was more than 70% and each of their outcrossing setting rate was more than 11%.2、To understand the genetic diversity of 20 parent material of rice((909A、910A、911A、912A、913A、914A、915A、916A、917A、918A; Minghui63、Minghui86、Fuhui838、Shuhui527、Mianhui725、Enhui58、Miyang46、R189、R894、Shuhui162), this study used 84 pairs SSR primers to amplificate those materials’ DNA by using of the SSR marking technique, 64 pairs of primers displayed well in polymorphisms, detected a total of 314 polymorphic locus, an average of 4.91 alleles. The value of allelic polymorphism information content(PIC) ranged from 0.375~0.887, an average of 0.698. The molecular phylogenetic trees constructed by UPMGA based on genetic similarity coefficients among 20 parents materials showed that the Recovery system materials and Male sterile line materials divided into two categories at the genetic similarity coefficients is 0.57, and also the results indicated the 10 New CMS lines have a narrow genetic background and low heterogeneity.3、13 male sterile lines(909A、910A、911A、912A、913A、914A、915A、916A、917A、918A、919A、Jin 23A、D44A)and 10 restorer lines(Minghui63、Minghui86、Fuhui838、Shuhui527、Mianhui725、Enhui58、Miyang46、R189、R894、Shuhui162) were used to create 130 F1 hybrids by the way of incomplete dialect cross( NCⅡ). The studies included the simple correlation anlysis among 11 agronomic characters(plant height、panicle length、days to heading、1000 grain weight、effective panicle per plant、single plant yield、filled grain per panicle、total spikelets per panicle、outcrossing setting rate、grain density per panicle and flag leaf length) and the analysis of combining ability. The main results were as followings:(1)The results of this part of the research showed all restorer lines’ mean squares of GCA(general combining ability) were bigger than sterile lines’, and all of the 11 traits we investigated affected by restorer lines’ GCA effect and combine SCA effect at significant or extremely significant level, three traits including the filled grain per plant, 1000 grain weight, plant height which affected by sterile lines’ GCA effect at significant level and others at non-significant level. There were extremely significant or significant levels of GCA and SCA with the filled grain per plant, 1000 grain weight, plant height. There were extremely significant or significant levels to GCA and SCA, which were both affected by restore lines, with the days to heading, single plant yield, total spikelets per plant, outcrossing setting rate, flag leaf length, panicle length, grain density per panicle, effective panicle per plant. In this study, most agoronomic traits were affected by both of additive gene effects and non-additive gene effects, The additive gene effects were principal in days to heading, outcrossing setting rate, 1000 grain weight, flag leaf length, panicle length, grain density per panicle, plant height, while the non-additive effects was greater in single plant yield, total spikelets per plant, filled grain per plant, effective panicle per plant and so on.Anyway, most traits were influenced more greatly by restores lines than by sterile lines.(2)The results of we investigated about the agoronomic traits of 130 hybrids and the effect values of SCA and GCA showed that GCA and SCA are independent to each other. The effect of GCA of the same traits were different and the effect of GCA of the same material but different traits were also different. The SCA effect has non-significant relation to the actual performance of hybrids, SCA effect was not absolutely determined by GCA effect, but there existed a positive correlation between GCA and hybrids’ actual performance of agoronomic traits, the parent GCA effect was better, the chance of high SCA effect value and hybrids’ actual performance were bigger.Considering the combining ability effect value and hybrids’ actual performance, 5 steriles(910A,913 A,915A,918 A,919A) had a better performance than others.4、The 913 A, 915 A, 918 A were three good CMS Lines in breeding application for their fine comprehensive characters.