Studies On Inheritance Of Dwarf Characters In Indica Rice(Oryza Sativa L.)

For investigating the linkage group to which the semidwarf gene sd-t belongs, the crosses between Aitaiyin 2(ATY2), a variety of sd-t carrier in indica rice, and marker stocks as well as the trisomic lines of 1R36 were made. The results indicated that the sd-t gene was linked to the marker genes Prp-b(Purple pericap b)~ lg(ligueless)~ Wh(White hull). It was inferred that the sd-t gene was located on chromosome 4 according to the established relationship between chromosomes and linkage groups.For investigating the linkage group to which the semidwarf gene sd-n belongs , the crosses between Yizhilashuangai(YZLSH), a variety of sd-n carrier in indica rice, and marker stocks as well as the trisomic lines of 1R36 were made. The results indicated that the sd-n gene was linked to the marker genes Bh(Black hull)~ nl-i(neck 1eaf)~. gh-i(gold hull-i). gl(glabrous leaf) . It was inferred that the sd-n gene was located on chromosome 5 according to the established relationship between chromosomes and linkage groups.In order to improve the traits of semidwarf genes non allelic to sd-I, the test crosses between Nanjing 11 and the attained lines were carried out. There were ii lines carrying semidwarf genes non-allelic to sd-l in the selected 49 lines. We have gotton the mutant from irradiation in Xintaiai and the improved traits of the generation from crosses between Yizhila and Tianegu and crosses between sd-g near-isogenic lines and tall varieties.