الفهرس 
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Abstract
The main objectives of the present Study were to :1-Evaluation of segregating populations under new reclaimed lands conditions.Selection, the desirable families under new.3-Estimation of simple correlation of among all the studied traits.4-Estimation of phenotypic and genotypic coefficient of variations heritability and genetic gain for the selection methods of the two Crosses during segregated generations from F2 up to F4 generations).5- applied different selection procedures at the early segregating generations of the two Crosse The experiments were carried out during three successive seasons; 2019, 2020 and 2021 at at farm west of Minia, under new reclaimed lands conditions Randomized complete block design of three replications was used in all experiments.
The two Crosses were originated from of the cross between:-
1- Cross 1 (Giza 80 X Giza 90).
2- Cross 2 (Giza 95 x Super Giza 86).
The Pedigree selection and bulk sample to improve seed cotton yield were con ducted using the above two cross of cotton in F2, F3 and F4 generations.
Results obtained could be summarized to the main following topics:
1- Evaluate the mean performance for the F2 population of the two crosses and their parents during 2019 season.
2- Evaluate the mean performance for the F3 families of the two crosses and their parents during 2020 season.
3- Evaluate the mean performance for the F3 of the Two Crosses families
and their parents during 2021 season.
4- Estimation of phenotypic and genotypic Coefficients of variations, heritability and genetic gain for the Two selection methods of the Two Cotton crosses during segregated generations (from F2 up to F4).
1-Evaluate the mean performance for the F2 crosses
1-Seed cotton yield /plant in the F2 generation of cross 1 ranged from 20.26 to 173.20 gm. with an overall mean of 65.74 gm. and ranged from 16.40 to 186, 00. gm. with an overall mean 57.06 gm. for Pop 2. Indicating wide range of variability of both cross and selection for seed cotton yield could be effective.
2-Comparing the overall mean of the two cross with the parental to direction of dominance was towards the batten seed cotton in cross 1 However, in cross 2 the direction partial dominate was towards to the low yielding seed cotton in cross 2.
3-The coefficient of variability in seed cotton yield were very high indicating ability for selection seed cotton yield in F2-generation of the two crosses.
4-Estimates of heritability in broad sense for seed cotton yield were intermediate by 44.41% of cross l and 51.31% of cross 2 respectively.
5Correlation coefficient of seed cotton yield per plant was highly significant positive for both crosses for with all studied traits except boll weight of cross. 1 and seed index of cross. 2 indicating that selection for seed cotton yield may resulted in increase in these traits.
2. Evaluation of pedigree selection for seed cotton yield in F3-generation, season 2020.
1- Highly significant differences found among the selected families for the selection criterion; seed cotton yield per plant and all the correlated trait except uniformity ratio of cross. 1 and lint percentage and boll weight of cross 2.
2- Seed cotton yield / plant ranged from 74.23 gm. to 155.30 gm. with an average 105.73 gm. of cross 1 while, in cross 2 seed cotton yield ranged from 46.97 to 160.47 with average 86.06 gm.
3-The average direct response from selection in percentage of the unselected bulk sample of seed cotton yield was lower than the bulk by (-9.37% and -7.86%) of cross 1 and cross 2, respectively.
4-Based on the better parent average observed gain was showed insignificance decrease (-2.58 %) of cross 1 and significant (-33.56%) of cross 2 in seed cotton yield per plant.
5-Seed cotton yield / plant showed positive genotypic and phenotypic correlation with each of lint yield, lint percentage, number of bolls per plant and lint index of the two crosses in F3 generation. These values of correlation were in the same trend of phenotypic correlation in F2 generation.
3-Evaluation of pedigree selection for seed cotton yield in F4-generation, season 2021.
1-Significant differences were found among the selected families for the selection criterion; seed cotton yield, in addition lint yield/plant and number of bolls/plant in both crosses and boll weigh, fiber fineness (Mic) and uniformity ratio of cross. 1 and for lint percentage and fiber length (FL) of cross. 2. Indicating sufficient retained genetic variability for further cycles of selection for these traits.
2- Mean the selection criterion; seed cotton yield of the thirty selected families in cross. 1 in the F4-generation ranged from 53.33 to 166.00 with an average of 100.67 gm. Only seven selected families in cross 2, No. 1, 4, 13, 17, 18, 20 and 25 were higher than the better parent Giza 90 and the bulk sample in seed cotton yield and lint yield per plant, in addition four families no. 3, 9, 16 and 28 were high yielding comparable the bulk sample.
3-Mean seed cotton yield of the thirty selected families in cross. 2 in the F4-generation ranged from 59.13 to 165.47 with an average of 100.82 gm., Only two families; No.6 and No.9 were higher than the better parent Giza 95 and bulk sample in seed cotton yield, lint yield/plant and number of bolls /plant.
4- Selection for seed cotton yield resulted in insignificant increased for number of bolls / plant than the bulk sample and insignificant increased for lint percentage compared to the better parent of cross 1. Moreover, insignificant increased for seed cotton yield, lint yield/plant and lint percentage compared to the bulk sample and lint percentage and index compared to the better parent of cross 2.
5-Phenotypic coefficient of variability; PCV % was slightly larger than the genotypic coefficient of variability GCV% for all traits in the two crosses The narrow differences between GCV and PCV% in both crosses resulted in high estimates of broad sense heritability for the seed cotton yield by 97.10% of cross. 1 and 93.67% of cross. 2.
6-After two generations from selection for seed yield cotton per plant in cross. 1, seven selected families no 1, 4, 13, 17, 18, 20 and 25 out yielded highly significant the unselected bulk sample in F4-generation. Five selected families of no.1, 13, 17 18 and 25 surpassed highly significant the unselected bulk sample for lint yield per plant and number of bolls per plant. Families, no. 1 and 25 were showed highly significant positive than the unselected bulk sample for fiber strength.
7- Five selected families, no 13, 17, 18, 20 and 25 were showed highly significant increase compare to the better parent for seed cotton yield and lint yield per plant.
8- Average of observed direct and correlation response to selection for the selection criterion SCY/P in percentage the batter parent resulted in highly decrease for SCY/P and negative response to selection for the most correlated traits.
9-Concerning cross 2, the overall mean of the 30 selected families showed insignificant increase in the selection criterion; seed cotton yield per plant than the unselected bulk sample and insignificant increase in the most correlated traits.
10- Four selected families no. 2, 6, 9 and 20 were showed significant increase compared to the bulk sample of the selection criterion seed cotton yield/plant and increase in two correlated traits lint yield/plant and number of bolls per plant. Moreover, the families, no.3 and 19 surpassed significant the bulk sample in the selection criterion.
11- Nine selected families, no. 5, 10, 11, 12, 14, 15, 21, and 22 were showed in significant increase in selection criterion seed cotton yield/pant than the bulk sample. Also, the same nine families in addition no. 3 and 19 were showed insignificant increase compared the bulk sample in lint yield/plant.
12- For the selection criterion compared to the better parent, average the 30 selected families showed negative insignificant response to selection by -18.33%. and insignificant decrease in most correlated traits;
3- Phenotypic and genotypic correlations coefficients among traits in F4-generation.
Seed cotton yield per plant showed positive genotypic and phenotypic correlation coefficients with lint yield per plant, number of bolls per plant in F4 – generation of both crosses While, negative correlations were found between SCY/P and each of lint percentage and lint index in cross 1 in F4 – generation.