| 26 indica rice restorer lines containing Lepidopteran-resistance gene crylAb/Ac and 11 indica rice restorer lines containing Lepidopteran-resistance gene crylC* developed were used as male parents.11 indica photo-thermo-sensitive genic male sterile lines and one cytoplasm male sterile line were used as female parents. NCII mate model was used for madding crosses by p X q. Two set experiments were conducted. Ten agronomic traits including yield per plant and yield compernents were investigated and analyzed for general combining ability of parents and specific combining ability of hybrids. The Bt protein contents of ten restorer lines and seven crosses were tested. The rice grain quality of restorer lines and their hybrids were analyzed.1. The general combining ability (GCA) of all traits is significant at 0.05 levels. Except for the panicles per plant and the panicle length, specific combining ability (SCA) of all other traits is significant at 0.05 levels. And the additive effect is more important than the dominant effect for influencing the genetic variation of the population.2. Although GCA was independent from SCA for each trait in parent lines, each agronomic trait can be influenced by both GCA and SCA. However, the parent lines which have higher GCA have not always the same high level of its SCA. The combination which performed well has at least one parent line of high GCA whatever its level of SCA.3. The Lepidoteran-resistant restorer lines with better GCA and SCA of main agronomic traits in combining ability analisis were WH836, Huakanghui304, Huakanghui305, Huakanghui310, Huakanghui345, TY8526, TY8532 and TY8533. The male sterile lines with better GCA and SCA of main agronomic traits were Hua201S, Hua328S, JufengA, Guangzhan63S-2, TianyuanS and XinhuaS.4. Some superior heterosis combinations have been selected preliminary through combining ability analysis and test crosses. The 20 chosen combinations are as follows:Hua893S/WH836,Hua891S/WCY838,Hua893S/WCY838,Hua893S/Huakan ghui464,Hua328S/WCY838,Hua893S/Huahuilhao,Hua891S/Huahuilhao,Hua891S/ Huahui212,JufengA/Huahui212,Hua328S/Huahui212,Hua328S/Huakanghui331,Hua 893S/Huakanghui331,Guangzhan63S-2/TY8526,Guangzhan63S-2/TY8530,Hua888S /TY8531,TianyuanS/TY8532,Guangzhan63S-2/TY8532,Guangzhan63S-2/TY8533,T ianyuanS/TY8536, Guangzhan63S-2/TY8536.5. The result of Bt protein assessment showed that it not has significant difference between hybrid F1 plants and their parent lines in Bt expression, of which the result elucidate that some related genes can be expressed stably in hybrid progenies. And field examination of stem borer resistant ability showed that both the hybrids and their parent lines have high resistance against Lepidopteran including striped stemborer (Chilo suppressalis), yellow stemborer (Tryporyza incertulas) and leafforders (Marasmia patnalis and Cnaphalocrocis medinalis).6. The results of agronomic traits measurement showed that there are no significant difference between the introgressed lines and their donor lines. Meanwhile, the negative correlation was significant at 0.01 level between Cry1C* expression and spikelet number of seed per panicle,number per plant,yield/plant and percentage of seed-setting in period of tillering. And the positive correlation was significant at 0.01 level between Cry1C* expression and spikelet number of seed per panicle,number per plant,yield/plant and percentage of seed-setting in period of jointing.7. The result of grain quality analysis for 20 superior heterosis combinations showed that some of them achieved A level of national standard.8. The result of grain quality correlation analysis showed that there are correlation ships in different degree between each two grain quality traits as which means that we must take into consideration of the influence to other traits while choosing a certain trait.
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