Genetic Analysis of Some Yield Components in Half Diallel Sweet Corn Crosses

A half diallel set of crosses among six inbred lines of sweet corn was evaluated to study heterosis and combining ability among plant height, ear height, ear diameter, number of rows per ear and ear yield per plant. The study was carried out at the agricultural research center in, GCSAR, Lattakia, Snoubar Jableh, during the 2010, 2011 seasons. Result showed that almost all crosses expressed a significant positive heterosis effect for ear yield per plant relative to mid parents and better parents; whereas, the highest positive significant percentage of heterosis for ear yield per plant were expressed by the crosses (L4xL6) which gave (198.70%, 176.81%) and (L4xL6) which gave (196.94%, 168.56%), over mid parents and better parents, respectively. The ratio (σ2GCA/σ2SCA) which was less than (1) showed that the non-additive gene action was more important than the additive gene action in all traits except plant height and ear height. The inbred lines L3 (17.061) and L4 (12.011) seemed to be the best general combiners for ear yield. Also, based on SCA effects, many of single crosses were identified as superior for ear yield, and the best hybrid was L3xL5(50.173).

Evaluation of Heritability and Genetic Advance for Yield and Fiber Traits Among Cotton F2 Hybrids

This research has been carried out at the experimental Station of Agriculture Faculty, Damascus University during the period of 1998-2000. Five parents were selected from the Cotton Office Germplasm (Aleppo40, Raqua5, Dir22, Daltabain50, 88G6104) to examine the inheritance of some morphophysiological, yield, and quality related traits. In1998, the five parents were hand-crossed in all combinations (with no reciprocals) generating ten F1 hybrids. During 1999, the ten crosses and their parents were planted to produce F2 seeds. In 2000 the F1s, F2s, and their parents were grown in a randomized complete block design with two replications. Heritability estimates in broad sense showed that the earliness traits possess the highest values, followed by total and actual bolls number, indicating the importance of additive gene action in the inheritance of these traits. Whereas, heritability values for other traits were markedly different, revealing the genetic diversity of these hybrids parents. High estimates of expected genetic advance were found to be associated with high heritability estimates for total and actual bolls number, indicating that direct selection should be effective for these traits. On the other hand, improvement of traits, possessing intermediate estimates of genetic advance and high heritability estimates, such as total bolls number, harvest index, flowering earliness and fiber elongation in some studied hybrids, through direct selection might be less effective. The results suggest that traits with high heritability estimates associated with low estimates of genetic advance; and those possess intermediate estimates of heritability and genetic advance or low estimates of both parameters are most likely controlled by non-additive genes, therefor, direct selection might not be effective for improving these traits.

Genetic analysis for yield and its components in hybrids of chickpea (Cicer arietinum L.)

A half diallel making design was used to determine combining ability and heterosis of six chickpea lines and their hybrid combinations with R.C.B.D. in three replication for seed yield per plant, number of pods per branch, pods number per plant, first pod height and 100- seed weight, during 2015 and 2016 seasons, at the research Center of Al-Gab (G.C.S.A.R). Genotypes, general (GCA) and specific (SCA) combining ability mean squares were significant for all studied traits. The ratio σ2 GCA / σ2 SCA were detected for all traits and showed that non- additive gene action was more important than additive gene action in controlling all studied traits. GCA effects showed that the lines P2(IL.10158) was good general combiner for number of pods per branch and plant, also, 100- seed weight where, P3 (IL.5883) and P4(IL.4) were good general combiner for first pod height and seed yield per plant, respectively. SCA effects showed that(P1×P2) hybrid was the best F1 crosses combination for seed yield per plant. On the other side (P1×P2), (P1×P4) and (P2×P4) were showed positive and significant heterosis values for seed yield per plant and 100- seed weight also first pod height and number of pod per branch and plant respectively.

Combining ability analysis for seed yield and some yield compenents traits in six lines of chickpea (Cicer arietinum L.)

A half diallel making design was used to determine combining ability and heterosis of six chickpea lines and their hybrid combinations with R.C.B.D. in three replication for seed yield per plant, number of pods per branch, pods number per plant, first pod height and 100- seed weight, during 2015 and 2016 seasons, at the research Center of Al-Gab (G.C.S.A.R). Genotypes, general (GCA) and specific (SCA) combining ability mean squares were significant for all studied traits. The ratio σ2 GCA / σ2 SCA were detected for all traits and showed that non- additive gene action was more important than additive gene action in controlling all studied traits. GCA effects showed that the lines الإسباني was good general combiner for traits:seed yield per plant, pods per plant, 100- seed weight, days to maturity, protein per cent. SCA effects showed that(Algerian×Spanish) hybrid was the good specific combiner for seed yield per plant, pods per plant, 100- seed weight, harvest index. On the other side(Algerian×Spanish) was showed significant desirable heterosis values for seed yield per plant and 100- seed weight, days to maturity, harvest index.