الفهرس 
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Abstract
The present investigation was conducted in Agronomy Department-Faculty of agriculture –Tanta University and Sakha Agricultural Research Station, A.R.C., Egypt, during three growing seasons, 2019, 2020 and 2021. The main objectives of the present investigation were carried out to: Using pedigree selection method to improve some of economic traits for two crosses of Egyptian cotton. - selection some genotypes which have less effect for late planting date . Two crosses of Egyptian cotton were used in this study: Karshenky 2 ( R 101) × Giza94 and Suvin ( D101 ) x Giza 96. In the first season, F2 of the two crosses and their original parents will be grown in non-replicated rows. All plants will be self-pollinated. The top 5% among F2 superior plants will be selected for each of the studied traits (yield and yield component characters). In the second season, all superior plants will be grown with original parents and the F3 plants will be selected such as in F2 . In the third season, the selected families F4 will be grown with original parents under two planting dates. Three replicates will be grown in Randomized Complete Block Design (RCBD). Studied traits : 1) Earliness characters and plant height trait : 1- First fruiting node ( F.F.N. ) 3 - Days to first open boll ( DFB ) 2- Days to first open flower ( DFF ). 4 - Plant height ( P.H. ) 2) Yield and yield component traits: 1- Seed cotton yield ( S.C.Y. ) / plant. 4 - Boll weight ( B.W. ). 2- Lint yield ( L.Y. ) / plant. 5 - Seed index ( S.I. ) ( g ). 3- Lint percentage ( L % ). 6 - Lint index ( L.I. ) ( g ). 3) Fiber properties: 1- Fiber fineness ( micronaire value ). 3 - Fiber length ( F.L. ) ( mm ) 2- Fiber strength ( g / tex ). 4 - Uniformity ratio ( U.R ). The obtained results could be summarized as follows: • Pedigree selection • Means, range, phenotypic, genotypic coefficients of variation, phenotypic and genotypic variances: Means, ranges, phenotypic, genotypic coefficients of variation, phenotypic, genotypic variances and heritability in broad sense of all the studied traits in F2 and F3 generations in population I and population II . The results showed that means of most studied characters were increased in F3 after one cycle of pedigree selection. The ranges for all characters in F2 generation were wider than in F3 generation. Phenotypic variances for all studied characters were highly significant. The results indicated that high variation within every population allowed achieved improvement inter population in most selected characters. The first fruiting node, lint yield, seed cotton yield, lint index, boll weight, Micronaire value, seed index and lint index exhibited the highest phenotypic and genotypic coefficients of variation estimates in F2 generation because of the large amounts of differentiation between the two parents. Means, range, phenotypic, genotypic coefficients of variation, phenotypic, genotypic variances and heritability in broad sense of all the studied traits in D1 and D2 in F4 generations in population I and population II. The results indicated that mean performance was higher in first date ( D1 ) than late planting date ( D2 ) in most studied characters and was higher than in both F2 and F3 generations. Phenotypic variances showed highly significant in all characters indicated high genetic variability among selected genotypes in all characters. Also, the heritability in broad sense was high in most characters indicated high genetic variances relative to phenotypic variances in F4 generation at both planting dates in both populations. Phenotypic and genotypic coefficient of variance in first fruiting node, seed cotton yield plant-1 and lint cotton yield plant-1 in both populations at two planting dates were higher than other characters. Genotypic and phenotypic correlations: The phenotypic and genotypic correlation between studied characters in F2 and F3 generations : Population I : The genotypic correlation between three earliness characters were highly significant negative with most yield characters in F2 Pop.I . While phenotypic and genotypic correlation between earliness characters with yield characters in F3 generation were positive and non-significant except for lint percentage was highly significant positive. Genotypic correlation was highly significant positive among most yield and yield components characters in both generations. In the same trend highly significant positive correlation among three earliness characters in both F2 and F3 generations. Phenotypic and genotypic correlations between three characters; boll weight, seed index and lint index were high significant positive in both generations. The phenotypic correlation between Micronaire value ,fiber length and Presley index and uniformity ratio were high significant negative in F2 generation changed to weak and non- significant negative in F3 generation. While, fiber length, Presley index and uniformity ratio were high significant positive in both generations. Population II : Highly significant negative genotypic correlation between first fruiting nod, days to first flower and days to first open boll in F2 generation was obtained. While after applying pedigree selection changed to highly significant positive in F3 generation. The genotypic correlation between earliness characters and yield and its components was insignificant in this population. The phenotypic and genotypic correlation between most yield characters showed high significant positive inter population II .The genotypic correlation among fiber properties; Presley index, fiber length and uniformity ratio were highly significant positive in both generations. The phenotypic and genotypic correlation between studied characters in D1 and D2 in F4 generation. Population I (R101 X G.94 ): The phenotypic and genotypic correlation between DFF and DFB was highly significant positive in D1 and D2. Also, phenotypic and genotypic correlation between DFB and plant height was highly significant positive at both planting dates. Two earliness characters DFF and DFB and PH were significant and highly significant negative correlation with all yield and yield components in both planting date. Population II : The results exhibited significant and high significant phenotypic and genotypic correlations between DFF, DFB and all yield and yield components except for lint percentage at late sowing date ( D2 ) and for boll weight, seed index and lint index at first sowing date ( D1). On the contrary, the phenotypic and genotypic correlations between earliness and yield characters were significant negative in the population I. The phenotypic and genotypic correlations were highly significant positive between most yield characters in both sowing dates. On the other hand, the association between fiber properties and others studied characters was insignificant in D1 and D2 except for fiber length and FFN at late planting date. 4.1.4. Genetic advance of cotton yield and correlated traits. • Improvement in three earliness characters and plant height trait: - Predicted advance, selection advance and actual genetic advance in three earliness characters and plant height trait of both populations as a result of applying pedigree selection for 10 economic characters: Population I : The pedigree selection for FFN, DFF and DFB were high predicted genetic advance and selection advance in F2 generation and recorded high actual genetic advance in F3 generation. The predicted improvement in first fruiting node through pedigree selection for FFN was highly positive ( undesirable value ). While the pedigree selection for seed index and lint index gave best negative predicted advance ( desirable value ). Improvement in three earliness characters was negative values indicated on high genetic advance ( Δ G ) while, all values positive were indicated non response to improvement in earliness characters. Predicted genetic advance for days to first flower, all pedigree selection for seed cotton yield, lint cotton yield, lint percentage, seed index and lint index were the highest predicted advance .While, the highest actual advances in days to first flower were pedigree selection for DFF, DFB, FFN and seed cotton yield plant-1. The pedigree selection for seed cotton yield plant-1, lint cotton yield plant-1, lint percentage, seed index and lint index characters were high predicted and selection advance in days to first open boll (DFB) trait . Population II : The pedigree selection for FFN , DFF , DFB and PH showed highly predicted genetic advance , selection advance in F2 generation and recorded high actual genetic advances in F3 generation. Estimation of actual advances in FFN from F3 generation showed that the pedigree selection for FFN, DFF, DFB and PH gave the highest actual value , respectively .The highest Predicted genetic advance of days to first flower was recorded by pedigree selection for seed cotton yield, lint cotton yield, lint percentage, seed index and lint index. While , the highest actual advances of days to first flower were recorded by pedigree selection for DFF, DFB ,FFN and seed cotton yield plant-1 . The pedigree selection for seed cotton yield plant-1, lint cotton yield plant-1 , lint percentage, seed index and lint index were highly predicted and selection advance in days to first open boll trait. Generally, the pedigree selection for three earliness characters; FFN , DFF and DFB were higher predicted genetic gains in F2 generation than other pedigree selection, although this values were positive ( undesirable ). The high actual genetic advance in earliness characters were for pedigree selection for three earliness characters . Improvement in yield and yield components : Population I : Pedigree selection for seed cotton yield and lint cotton yield plant-1 gave maximum predicted advance and highest actual advance and actual % in F3 generation for seed cotton yield and lint cotton yield plant-1. Improvement in lint percentage through pedigree selection for lint percentage, lint cotton yield plant-1 and lint index were predicted the highest genetic advance in lint percentage. This may be due to highly significant genetic positive correlation among the three characters. Genetic gains from applied pedigree selection for the 10 traits were value as indicated actual increased mean performances for progenies about basic F2 population in all selected characters. The best improvement in boll weight, seed index and lint index in predicted and actual were for applying pedigree selection for three characters. Population II : The selection advances for the six yield and yield components were obtained by applied pedigree selection for those characters. Pedigree selection for seed cotton yield obtained high predicted and actual advance in seed cotton yield plant-1, lint cotton yield plant-1 and other related characters. The actual advances estimation from F3 were nearly with predicted advances in most pedigree selection indices. • Predicted advance , selection advance and actual genetic advance as a result of applying pedigree selection : Population I : The results showed that highly predicted genetic gains in FFN through pedigree selection for FFN,LP, DFF, DFB ,PH and LI, respectively. Actual gains in FFN due to pedigree selection for boll weight and plant height in F4 generation were lower than predicted genetic obtained of F3 generation. Improvement in DFF, the pedigree selection for DFF, DFB, LP, LI and FFN were higher predicted and selection advances than other indices. The actual gains in DFF of F4 generation were negative and lower than predicted genetic gains. The results indicated that the highest predicted genetic advance for DFB occurred when selecting for DFB, DFF, LP, FFN and LI , respectively. While the actual gains of F4 were very low and negative values in all pedigree selection indices. Pedigree selection for plant height was highly predicted and selection advance. Actual gains in PH of F4 generation highly positive were high in all pedigree selection except pedigree selection for plant height trait itself . Population II : Actual gains in FFN were for pedigree selection for lint percentage , lint index and lint cotton yield plant-1 and the actual gains of F4 generation were lower than predicted genetic obtained of F3 generation, the results indicated that improvement in earliness characters in population II were lower than population I. Improvement in DFF; the pedigree selection for DFF, DFB, FFN and PH were higher predicted and selection advances than other indices. The actual gains in DFF of F4 generation were negative and lower than predicted genetic gains. In the same trend, the improvement in DFB traits predicted, selection advance of F3 and actual ( realized ) genetic gains of F4 generation: the results indicated that the highest predicted genetic advance for DFB occurred when selecting for DFB, DFF, LP, FFN and LI , respectively. While the actual gains of F4 were very low and negative values in all pedigree selection indices. Improvement in yield and yield components of F3 and F4 : Population I : All pedigree selection for three earliness characters and plant height trait showed low predicted advance in yield and yield components. Pedigree selection for seed cotton yield plant-1 and lint cotton yield plant-1 gave maximum predicted advance and highest actual advance and actual % of both F3 and F4 generations. The predicted and actual genetic advances were high and equal in values in both pedigree selection for seed cotton yield plant-1 and lint cotton yield plant-1. Improvement in lint percentage through pedigree selection for lint percentage, lint cotton yield plant-1 and lint index were highly predicted genetic advance in lint percentage. Genetic gains of applying pedigree selection for the 10 traits were highly positive value as indicated actual increased mean performances for progenies about basic F2 population in all selected characters. The best improvement in boll weight, seed index and lint index in predicted and actual were for applying pedigree selection for three characters the predicted of F3 and actual of F4 gains were nearly with values in pedigree selection for boll weight, seed index and lint index. Estimation predicted and selection advances in seed index and lint index the pedigree selection for seed index, lint index and boll weight were higher than other pedigree selection indices. Population II : Pedigree selection for seed cotton yield and lint cotton yield plant-1 gave maximum predicted advance and highest actual advance and actual % of both F3 and F4 generations for seed cotton yield and lint cotton yield plant-1. Also, the pedigree selection for seed index, lint index and boll weight were played major role in contributions in improvement as a predicted or actual genetic advance in both seed cotton yield plant-1 and lint cotton yield plant-1. Improvement in lint percentage through pedigree selection for lint percentage, lint index, lint cotton yield plant-1 and seed index were the highest predicted genetic advance in lint percentage. The best improvement in boll weight, seed index and lint index in predicted and actual were for applied pedigree selection for three characters the predicted of F3 and actual of F4 gains were nearly with values of pedigree selection for boll weight, seed index and lint index. All pedigree selection were high actual gains in two characters seed index and lint index. Predicted advance and selection advance in F4 generation in three earliness characters and plant height trait as a result of applying pedigree selection for 10 economic characters : Population I : The results indicated that all pedigree selection for FFN , DFF, DFB and PH were higher predicted and selection advances in three earliness characters and plant height respectively, than others pedigree selection, while all pedigree selection were low improvement in four previous characters .Improvement estimated of F4 generation of population I (R101 XG.94 ) were less than obtained of F3 generation. Population II : The results indicated that all pedigree selection for FFN , DFF, DFB and PH were higher predicated and selection advances in three earliness characters and plant height trait respectively, than others pedigree selection. The pedigree selection for FFN, LP % and LI were highly predicted and selection advances in FFN character. Relative to improvement in DFF and DFB the pedigree selection for DFF, DFB, SCY / P, LCY / P, BW ,SI and LI were high predicted genetic advance in both DFF and DFB respectively. The pedigree selection index was highly predicted and selection advance in PH character. Improvement estimated of F4 generation population II (D101 XG.96 ) was less than that obtained of F3 generation. Predicted advance and selection advance in F4 generation of six yield characters as a result of applying pedigree selection for 10 economic characters : Population I : Pedigree selection for SCY / P, LCY / P, SI, LI, BW and LP % were highly predicted , selection advances% and comparative predicted advances% in SCY / P and LCY / P respectively. On the other hand, all pedigree selection for earliness character were decreased in improvement in SCY / P and LCY / P where, exhibited low negative values in ( Δg ). The pedigree selection for LP % and LI were highly predicted, selection advance in lint percentage. Improvement in boll weight, seed index and lint index , all pedigree selection for three characters were high contributed in predicted and selection advances ( Δg ) those characters . Population II : Pedigree selection for SCY / P, LCY / P, SI, LI, BW and LP % were highly predicted , selection advances% and comparative predicted advances% in SCY / P and LCY / P respectively. On the other hand, all pedigree selection for earliness character were decreased in improvement in SCY / P and LCY / P where, exhibited low negative values in ( Δg ). The pedigree selection for LP % and LI were highly predicted, selection advance in lint percentage. Improvement in boll weight, seed index and lint index , all pedigree selection for three characters were high contributed in predicted and selection advances ( Δg ) those characters . Contribution of fiber characters in improvement three earliness characters and plant height through F2, F3 and F4 generations : Population I : The results indicated that all fiber properties were very low in predicted , selection advance% and comparative predicted genetic and most values were negative in three earliness characters and plant height trait through F2, F3 and F4 generations . Although , the genetic improvement depends on negative values, it is desirable in three earliness characters. In F2 and F3 generations, Micronaire value, fiber strength and fiber length were contributed greatly in improvement FFN , DFF, DFB and PH.