Comparison On Genetic Effect Of S₅～n Alleles From Different Wide Compatibility Varieties In Rice(Oryza Sativa L.)

In order to study the genetic effect of wide compatibility gene S5n from different wide compatibility varieties(WCVs) in rice (Oryza sativa L.) , near isogenic lines with S5n from different varieties were crossed with indica-japonica test varieties representing different ecotypes. By the fertility of the hybrids, the genetic effect of S5n from the different original WCVs in identical geneitc background and that of S5n from an identical original WCV in different geneitc background were compared. At the same time, in order to compare united effect of several wide compatibility genes with the effect of a single wide compatibility gene S5n , the primordial wide compatibility variety Dular containing several WCGs and near isogenic lines containing S5n from Dular and genetic background from nanjing 11 and Ballila, respectively, was crossed with indica-japonica test varieties. The results were as follows:1. The near isogenic lines containing the S5n allele from different original WCVs . and genetic background from japonica variety Balilla were crossed with 20 indica-japonica varieties representing different ecotypes, the results indicated that genetic effect of S5n from different wide compatibility varieties was not completely same, and that the compatibility power and compatibility spectrum of near isogenic lines carrying S5n from different donors were different. The compatibility power and compatibility spectrum of the near isogenic lines containing S5n from 02428 , Huanuo and Woaiga were higher and wider than that of the near isogenic lines containing S5n from Dular, CPSLO17 and Ketan Nangka.2.The performance of pollen and spikelet fertilities of F] between near isogenic lines of different donor and test varieties proved that pollen fertility and spikelet fertility2.The performance of pollen and spikelet fertilities of FI between near isogenic lines of different donor and test varieties proved that pollen fertility and spikelet fertility of the indica-japonica hybrid were controlled by different genetic system, and 85 locus only influenced the fertility of female gametes of F1 hybrids.3. In different genetic background, the genetic effect of near isogenic lines containing S5n from a wide compatibility variety was not different.4. The compatibility power and compatibility spectrum of Dular were better than that of near isogenic lines containing S5n from Dular. This result proved that united effect of several wide compatibility genes in Dular was indeed better than genetic effect of a single wide compatibility gene S5n from Dular.