水稻 遠緣交雜集團에 있어서 主要 形質變異

Study on the Variation of Major Characters in Remote Crosses of Rice (Oryza Sativa L.)

This study was conducted to obtain the basic information on the variation of major characters in remote crosses of rice. The heading date in the cross between Akihikari and Milyang 23 was controlled by major gene showing transgressive segregation for late parent in the F₂ population. The gene action for heading date in the cross between Akihikari and Milyang 23 or IR 36 would be different according to parents. Overdominance effect was observed for culm and panicle length in the F₁ generation, variation of panicle length in the F₂ population showed transgressive and continuous segregation. The F₂ segregation of five remote crosses for shattering habit showed a 9 : 7 ratio where easy shattering was dominant. The genes controlling shattering habit would be considered two pairs of dominant complimentary genes. Number of genes estimated in the F₂ population of five remote crosses showed 2-5 genes for culm length, 1-6 genes for percent of sterile grains, 1-8 genes for number of grains per panicle and 2-4 genes for days to heading. Dominance effect was very high for culm and panicle length.