| In this research,21varieties of South China Rice Core Germplasm in Huanghuazhan pedigree and RIL population derived from Huanghuazhan and SG-36were chosen as experimental subject. On the basis of pedigree re-sequencing, Illumina goldengate DNA chip system was developed to detect the whole genome high-throughput SNP markers and yield-related traits phenotype were studied systematically for four production quarter in two consecutive years. the results are as follows:Texianzhan25was the lowest in yield,5.92T/ha, Huanghuazhan’s ranked7with yield of7.42T/ha, Huangruanzhan was highest yield in the pedigree, which reaching8.38T/ha. Fengbazhan accounted minimum of2.21%, while the SG-36was maximum for18.06%in coefficient of variation. From the comparison of early and late years, Huanghuazhan and SG-36were significantly different on yield, Huanghuazhan got higher yield in early rice, while SG-36is more suitable for late rice cultivation. New varieties derived from Huanghuazhan inherited the high-yield characteristics and possess superior yield-related traits and gene combinations.Analysising the evolution of the yield and quality index, it can be found that the main genetic factors of yield rice improvement in core germplasm was the introduction of Teqing, which’s abundance of dwarf source to increase substantially in the green breeding improvement process, as the breeding goals change from high-yield to high-quality, the introduction of Changsizhan and Huasizhan increased the quality index significantly; while production declined rapidly. The yield and quality gradually balanced until Huanghuazhan.The core collection Huanghuazhan retains high-yield characteristics of Teqing and Jingxian89, and inherited quality blood from Changsizhan and Huasizhan, varieties derived from HHZ got differentiation on yield and quality subsequently. Comparison of gene segment from the core collection, the key changes in gene loci will produce more excellent new varieties adapt to the changing needs of breeding. By analyzing the re-sequencing data established on the basis of SNP maps, can be able to decipher these key features and the genotype interaction model, which will provide reliable theoretical guidance and practical solutions for Rice Yield Molecular Design Breeding.Stability of rice varieties was different vary yield-related traits, the stability of grain width and top leaf width were higher than the other traits, which’s stability coefficient were0.043and0.049; rice yield, with stability coefficient of0.178, was in the middle, the lowest traits was spikelets per panicle stability, with stability coefficient of0.935. Various varieties were quite different from yield-related traits on stability; yield stability coefficient was between0.023and0.35, of which Fengaizhan No.1accounted for the best and Shuanggui36the lowest. Schematic evolution from the pedigree of stability index showed that: the introduction of Changsizhan improved yield stability significantly in the pedigree. With the change of breeding objectives, stability index decreased, until the introduction of Molisimao, stability raise once again. The excellent varieties material screened by this study can be used as parental resources to cultivate new rice varieties with high stability of yield related traits, thus promoting the development of high and stable yielding rice breeding.In this research, recombinant inbred lines were built from significant difference in yield components of Huanghuazhan and SG36as parents for study on the phenotype in four continuous seasons. Through SNP markers genotype analysis of RIL population, we drawn a rice genetic linkage map which containing224polymorphic SNP markers and1575.08cM length. By using ICIMapping3.2software,186additive QTLs and174epistatic QTL of yield related traits were identified in four environments. Further analysis of QTL×Environment interaction found that171additive QTLs and124epistatic QTLs of yield related traits were identified, environmental factors impact on spikelets per panicle greater than grain type.The additive QTLs detected in this reseach covers almost all chromosomes, the reason maybe related with gene regulation the synthesis and accumulation of production distributed on almost all12chromosomes. there is consistency between the additive and epistatic QTL, some non-additive epistatic QTLs also involved in the formation of epistatic by modifying other genes work. The effects of detected epistatic QTLs were larger value, because of the epistatic QTL can improve the ability to detect relevant, which further illustrate the important role of epistasis in yield formation. Through further multi-environment tests (MET), analysing environment interaction effects, all additive QTLs were detected, indicating that the position of the marker interval yield-related traits are relatively stable, accurate and credible, including8QTLs appeared in three consecutive seansons and3interval contain five or more QTL,(SNP407-408, SNP503-504and SNP706-707), which has significance guidance for marker-assisted breeding. |
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