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POSSIBILITIES OF IMPROVEMENT IN COTTON, GOSSYPIUM HIRSUTUM L., THROUGH HYBRIDIZATION

Kalwar, Muahmmad Shaban (1998) POSSIBILITIES OF IMPROVEMENT IN COTTON, GOSSYPIUM HIRSUTUM L., THROUGH HYBRIDIZATION. PhD thesis, Sindh Agriculture University, Tando Jam.

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Abstract

Investigations were conducted during 1984 and 1985 seasons to mine the gene action of parents, i. e. Th 1174, Th 1100, H 59 1, In and Gregg 25, and 20 crosses in F1 and F2 generations, oped by a 5 parent complete diallel cross, for framing gression programme for improving quantitative characters of n, Gossypium hirsutum L. Each generation was raised in two onment i. e. with and without fertilizer to know the impact of rent environments and seasons on pattern of gene action. The s studied were plant height, number of sympodia, bolls per plant, weight, ginning percentage and seed cotton yield per plant. Analysis of combining ability showed that plant height was tioned by additive, nonadditive and plasma genes in F1, generation, t was also noted that all the above mentioned gene actions were y influenced by the environments, while in F2, exhibited that this was governed by additive genes only. In case of sympodia in F1, ation there was effect of additive as well as non additive genes, as only non additive gene effect was detected for this trait in neratioin. Number of bolls per plant and boll weight were rally controlled by additive genes, while only additive gene action was ayed in F2 generation. So far GCA effects are concerned, parent H 59 1 displayed rally positive and significant GCA effects in both generations and ns, while TH 1100 exhibited generally significant additive ts for both generations in 1984 season only for all the traits. e, H 59 1, is recommended to be included in hybridization programmed improving seed cotton yield. Three crosses i.e. TH 1174 x TH 1100, H 59 1 x HG 6 IN and H 591 gg 25 were identified as the best specific combiners for almost he traits. These hybrids also showed consistency regarding SCA ts in both generations and season. Therefore these crosses can ed in producing hybrid seed/promising varieties. When gene action, analysed by Hayman’ s approach, is considered, s observed that it remained changing with season and environment t number of sympodia per plant for which over dominance type of action remained constant in both environments and seasons. While remaining traits it varied from partial dominance to over ance in different environments and seasons. From Wr, Vr graphs, ion of varieties on regression line and r values indicated that plant height was controlled by dominant genes and Gregg 25 had most of the dominant genes. While TH 1100 had most of the sive genes. For number of sympodia it was observed that in E I th seasons it was conditioned by recessive genes and in E II, it nfluenced by dominant genes. In E I, TH 1174 had maximum dominant and TH 1100 and H 59 1 had most of the dominant genes and TH 1100, H 1174 had the maximum recessive genes. Number of bolls per plant controlled by recessive genes except in E II of 1984. Gregg 25, 1 and TH 1174 had the maximum dominant genes and TH 1100, HG 6, H 59 1 and HG 6 IN had most of the recessive genes in E I and of both the seasons. Nonsignificant negative r of Wr+Vr and tal values exhibited that there was more or less equal effect of ant and recessive genes in conditioning the boll weight. In E I, IN and H 59 1 and in E II, Gregg 25 had the dominant genes in s, while TH 1174 had most of the recessive genes in both onments and seasons except E II of 1984 which TH 1100 occupied lace. Highly significant negative r value suggested that ginning ntage was governed by dominant genes. In E I, HG 6 IN and TH 1100 and in E II, Th 1100 possessed maximum dominant genes, while, 25 possessed the recessive genes in excess in all environments seasons except E II of 1984 in which H 59 1 had the maximum sive genes. Negative r revealed that seed cotton yield per plant conditioned by dominant genes. The varieties which possessed um dominant genes were H 59 1 (E I of 1984), TH 1174 (E II of seasons) and TH 1100 (E I of 1985), the varieties having maximum sive genes were TH 1174 (E I of 1984) and HG 6 IN (E II of 1984, oth environments of 1985).

Item Type:Thesis (PhD)
Uncontrolled Keywords:Investigations were conducted during 1984 and 1985 seasons to mine the gene action of parents, i. e. Th 1174, Th 1100, H 59 1, In and Gregg 25, and 20 crosses in F1 and F2 generations, oped by a 5 parent complete diallel cross, for framing gression programme for improving quantitative characters of n, Gossypium hirsutum L. Each generation was raised in two onment i. e. with and without fertilizer to know the impact of rent environments and seasons on pattern of gene action. The s studied were plant height, number of sympodia, bolls per plant, weight, ginning percentage and seed cotton yield per plant. Analysis of combining ability showed that plant height was tioned by additive, nonadditive and plasma genes in F1, generation, t was also noted that all the above mentioned gene actions were y influenced by the environments, while in F2, exhibited that this was governed by additive genes only. In case of sympodia in F1, ation there was effect of additive as well as non additive genes, as only non additive gene effect was detected for this trait in neratioin. Number of bolls per plant and boll weight were rally controlled by additive genes, while only additive gene action was ayed in F2 generation. So far GCA effects are concerned, parent H 59 1 displayed rally positive and significant GCA effects in both generations and ns, while TH 1100 exhibited generally significant additive ts for both generations in 1984 season only for all the traits. e, H 59 1, is recommended to be included in hybridization programmed improving seed cotton yield. Three crosses i.e. TH 1174 x TH 1100, H 59 1 x HG 6 IN and H 591 gg 25 were identified as the best specific combiners for almost he traits. These hybrids also showed consistency regarding SCA ts in both generations and season. Therefore these crosses can ed in producing hybrid seed/promising varieties. When gene action, analysed by Hayman’ s approach, is considered, s observed that it remained changing with season and environment t number of sympodia per plant for which over dominance type of action remained constant in both environments and seasons. While remaining traits it varied from partial dominance to over ance in different environments and seasons. From Wr, Vr graphs, ion of varieties on regression line and r values indicated that plant height was controlled by dominant genes and Gregg 25 had most of the dominant genes. While TH 1100 had most of the sive genes. For number of sympodia it was observed that in E I th seasons it was conditioned by recessive genes and in E II, it nfluenced by dominant genes. In E I, TH 1174 had maximum dominant and TH 1100 and H 59 1 had most of the dominant genes and TH 1100, H 1174 had the maximum recessive genes. Number of bolls per plant controlled by recessive genes except in E II of 1984. Gregg 25, 1 and TH 1174 had the maximum dominant genes and TH 1100, HG 6, H 59 1 and HG 6 IN had most of the recessive genes in E I and of both the seasons. Nonsignificant negative r of Wr+Vr and tal values exhibited that there was more or less equal effect of ant and recessive genes in conditioning the boll weight. In E I, IN and H 59 1 and in E II, Gregg 25 had the dominant genes in s, while TH 1174 had most of the recessive genes in both onments and seasons except E II of 1984 which TH 1100 occupied lace. Highly significant negative r value suggested that ginning ntage was governed by dominant genes. In E I, HG 6 IN and TH 1100 and in E II, Th 1100 possessed maximum dominant genes, while, 25 possessed the recessive genes in excess in all environments seasons except E II of 1984 in which H 59 1 had the maximum sive genes. Negative r revealed that seed cotton yield per plant conditioned by dominant genes. The varieties which possessed um dominant genes were H 59 1 (E I of 1984), TH 1174 (E II of seasons) and TH 1100 (E I of 1985), the varieties having maximum sive genes were TH 1174 (E I of 1984) and HG 6 IN (E II of 1984, oth environments of 1985).
Subjects:Agriculture & Veterinary Sciences(a) > Agriculture(a1)
ID Code:295
Deposited By:Mr Ghulam Murtaza
Deposited On:01 Jul 2006
Last Modified:04 Oct 2007 21:00

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