Genetic Analysis On Yield-related Traits In Rice RIL Population Of Long Panicle And Big Grain

In recent year, raising yield potential in rice depends largely on morphological improvement and heterosis utilization.With the progress of science and technology and the development of breeding-related theories and methods, further insight into rice yield-related traits from different angle is a important subject to shape new ideal plant morphology of super high yielding rice, using theories and methods of mordern genetics. With the major genes plus polygenes mixed inheritance model of quantitative traits in plant and corresponding statistical methods, the genetic and correlation analysis was conducted about 28 traits of the recombinant inbred lines population (RILs, F₉), which is derived from MiYang46/FJCYD. The FJCD line was characterized by long panicles and big grains. The results were showed as follow.1. The analysis on the major genes plus polygenes mixed inheritance model indicated that among the yield and yield components traits, 1000-grain weight(1000GW) were controlled by a major genes and polygenes. Number of the spikelets of main panicle(NSMP), number of grains main panicle(NGMP), grain weight per plant(GWPP), rate of seed setting(RSS) and panicles number of per plant (PN) were all controlled by two pairs of major genes and polygenes. The major genes were recessive-epistatic, recessive-epistatic, complementary, additive and complementary effect. As to panicle length(PL) and branch(TB), PL was controlled by two pairs of genes with additive-epistatic effect and polygenes. Number of first branch(NFB), Length of first branch(LFB), number of second branch(NSB), length of second branch(LSB) and grain density(GD) were all controlled by two pairs of major genes and polygenes. The major genes were complementary, complementary, complementary, additive and additive-epistasis effect. Among grain traits, grain thickness(GT) and Grain width /grain thickness(GW/GT) were controlled only by polygenes. grain length(GL), Grain length/grain width(GL/GW) and Grain length /grain thickness(GL/GT) were controlled by two major genes and polygenes. The major genes were additive, additive and recessive-epistatic effect. Three pairs of major genes with additive-epistasis and polygenes played their roles in Grain width (GW). As to stem characters(SC), two pairs of major genes with additive-epistasis played their roles in plant height (PH). Two pairs of major genes and polygenes worked in culm length(CL), culm index(CI), stem diameter(SD), the lodging resistance of the basal culm(LRBC) and lodging resistance index (LRI). The major genes were recessive-epistatic, complementary, recessive-epistatic, recessive-epistatic and complementary effect. As to the canopy leaf characters(CLC), flag leaf area(FLA), penultimate leaf area(PLA), area of the third leaf from top(ATL) and grain-leaf ratio(GLR) were controlled by two major genes and polygenes. The major genes were additive, complementary, recessive-epistatic and additive-epistasis effect.