Inheritance studies for yield characteristics and earliness of pink bollworm - Resistant arboreum cotton

摘要

[Some germplasm lines of cotton, Gossypium arboreum L., that show resistance to pink bollworm (Pectinophora gossypiella) also carry agronomic properties, were crossed or combined to enhance derived germplasm lines. The objective of this study were todetermine (1) the agronomic performance of two pink bollworm resistance lines (HD 136 and HD 167) and two pink bollworm susceptible line (RG 8 and H 481), (2) gene effects for seed cotton yield, yield components and tarliness index, and (3) heterosis over better parent and over check variety (HD 167). Generation mean analysis of four parents a nd their three crosses grown at Hisar during 1990-91 revealed that HD 167 is the best source of resistance but late in maturity. Another aline RG 8 (146,96 g/plant) had a very high yield potential than that of HD I67 (80 g/plant). It was observed from 3-parameter analysis of pink bollworm damage that dominance component (h) was higher in magnitude than additive component whereas in case of earliness index additive component was more important. Duplicate type of epistasis was observed for seed cotton yield and number of bolls per plant. Desirable heterosis over better parent and over check variety was observed for bollworm damage, bolls per plant (HD 167×-H 481).