Study On The Characteristics, Heterosis, Combining Ability And Quality Of Three Newly-developed Sterile Lines

In this paper, the breeding characteristics, outcrossing, combining ability and heterosisof three newly-developed CMS lines was investiged. The result was as follows:1. Each CMS line showed the similar plant type, stable agronomic trait, abortedcompletely, the sterile plant rate was100%, typical abortive rate was more than99.8%,stained abortive rate was less than0.2%, spherical abortive rate was0.23A showedmoderate growth period, common plant type, but with a strong tillering ability;270A and11Ashowed lengthy growth period, better plant type, but with a common tillering ability.2. Each CMS line showed good outcrossing.270A showed the longest floweringduration, the highest stigma exsertion rate(SER) with84.1%and outcrossing rate with69.3%;23A showed the highest flowering percentage and the lowest indehiscent spikeletrate.3. Study on general combining ability(GCA) in yield component trait of these threeCMS lines showed as follows: Absolute plant(AP):23A>270A>11A; Panicle length(PL):23A>270A>11A; Seed setting rate(SSR):270A>23A>11A; Thousand kernelweight(TKW):23A>270A>11A; Yield per plant(YPP):270A>11A>23A.The study onspecial combining ablity(SCA) in yield component trait of the hybrid combinationsshowed as follows: WufengA/Changhui851showed the highest SCA of AP,270A/Changhui851showed the highest SCA of filled grain number per panicle(FGPP) and grainnumber per panicle(GNPP),23A/R319showed the highest SCA of SST and TKW,270A/R319showed the highest YPP.4. In the aspects of the heterosis, the hybrid combinations developed by23Aas femaleparent showed stronger transgressive heterosis(TGH) in PL and TKW, the hybridcombinations developed by270A as female parent showed stronger SOP in SSR;23Ashowed stronger competitive advantage(CA) in PL and TKW,270A showed stronger CA inSSR. the hybrid combinations developed by270A or23A as female parent were better thanthe hybrid combinations developed by11Aas female parent in heterosis.5. The rice quality traits of the CMS lines and hybrid combinations as follows: in theaspects of milling process quality,11A and23A were better than270A; On appearancequality, chalky rice rate(CRR) and chalk rice grade(CRG) of all the hybrid combinationswere influenced by restorer lines, PL and length to width ratio(T/W) of the hybridcombinations developed by270A or23A as female parent were influenced by CMS lines;On cooking and eating quality, the hybrid combinations developed by270A as femaleparent showed mediocre, the hybrid combinations developed by23A as female parent weresofter, the hybrid combinations developed by11Aas female parent were harder.