Abstract

                                A (7 x 7) parent diallet cross in G. arboreum L. was studied over four locations to estimate gene effects for seed and fibre characters. Ginning out-turn, seed index and lint index were observed to be controlled by both additive and non additve types of gene action whereas halo-length was predominantly controlled by additive gene action. Moderate to high heritability estimates in the range of 57-90% for ginning out-turn and 46-99% for halo-length were observed in different experiments. Seed index and lint index showed relatively low heritability estimates and the gene effects controlling these traits were not consistent in different experiments. One to two gene groups exhibiting dominance controlled ginning out-tum and lint index. In general, the gene effects were influenced to a considerable extent by environmental variation for all the traits except halo length for which gene effects were relatively stable. Implications of the study for designing appropriate breeding procedures with a view to improve ginn- ing out turn and halo length is discussed.

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