Genetical model analysis on main economical characters of fine fibre cotton G. Hirsutum L

Two new fine fibre lines were crossed with three high-yield varieties, Lumian 14, Zhongmiansuo 16 and Acala 4-42 in G. hirsutum L. in 5 x 5 diallel design up to 25 crosses. Wr/Vr regression formulae were established according to F1 data of the 9 characters by Hayman's method. Adequacy of additive-dominance model was tested, and 5 inheritance parameters i.e. D, H1, √H1/D, hN2 and hB2 were estimated. The results showed that the additive-dominance model was adequate for the fibre length, fibre strength, Micron, yield of unginned cotton, yield of ginned cotton, boll weight and bolls per plant, in which interaction between non-allelic genes was not significant. The additive effects were very important in genetical variations of the 3 fibre quality characters, i.e. fibre length, fibre strength and micron, by the graphic solution. And, the average degrees of dominance (√H1/D) of the three fibre quality characters indicated incomplete dominance in their F1 generation. Some increment genes concerned to the fibre length, micron and yield of ginned cotton were dominant, and others were recessive, which were different in different locus. Both hN2 and hB2 of the 3 fibre quality characters were higher