Nine inbred lines (S 5) of white maize derived from Giza-2 and IW-469 were crossed using of half diallel cross mating design, during spring season of 2019 at the Farm of Faculty of Agriculture, Al-Azhar University at Assiut Branch, to produce thirty six F 1 crosses. The parents, crosses and tow checks i.e. SC-163 and SC-10 were evaluated during spring season of 2020 in R.C.B.D with three replications to determine combining ability, heterotic and gene action effects. Significant differences were found among parental and their crosses as well as for general combining ability (GCA) and specific combing ability (SCA) for all studied traits. The previous results indicating the importance of both additive and non-additive genetic effects for studied traits. The ratio of Σg 2 i/ΣS 2 ij was less one for all studied traits, indicate that the non-additive gene action in the inheritance of all the studied traits. Parents P1 and P4 showed best GCA effects for grain yield/plant, while the parents P2 and P6 appeared to be the best general combiners for most of the studied traits. The crosses P1 x P8, P2 × P6 and P2 × P5 appeared to be the best mean performance, SCA and superiority percentage for most studied traits. The values of the broad sense heritability were high (>80%) for all studied traits. While, the narrow sense heritability was low for grain yield/plant (13.00%). Results indicated that some inbred lines could be used in breeding program to develop single crosses which have higher grain yield.

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This study was carried out during two winter successive seasons 2017/18 and 2018/19 to determine the effect of salinity stress on yield and yield components in F3 and F4 segregating populations of the two bread wheat crosses (Sakha 93 x Gemmaiza 9) Cross1 and (Sakha 93 x Giza 168) Cross II. The results showed highly significant differences between means of the two crosses and families for most the traits in F3, and 100 grain weight in F4 generations. The differences between salinity levels were highly significant for all traits in both F3 and F4 generations. The interaction between crosses × families was highly significant for all traits, except for number of grains/spikes in F3, while it was highly significant for number of grains per spike and weight of 100 grain in F4. The interaction between crosses × salinity levels was highly significant for all traits in F3, while it was highly significant for weight of 100 grain in F4. As for the interaction between families, salinity levels were highly significant for most traits in F3, while F4 were highly significant for weight of 100 grain. The interaction between crosses × families × salinity levels, were highly significant for most traits in F3, while in F4 were highly significant for weight of 100 grain. Highest values of H and GA were found for grain yield / plant and weight of 100 grain under salinity conditions in F4 generation. These traits would be improved by direct selection under saline soil conditions.

Combining ability analysis , heritability and heterosis were studied for earliness, as well as maturity , yield and some of its components in five diverse soybean (Glycine max "L." Merril) genotypes, which were crossed in a dillel mating pattern. Results revealed significant differences among the 25 genotypes, for all, the studied traits. General and specific combining abilities were also significant except for number of seeds/pod and 100-seed weight in g.c.a., indicating the importance of both additive and non-additive gene effects. The genotype MBB 80-133 was positively a high general combiner for all attributes except number of days to flowering and maturity. It was the best parent for seed yield /plot. The crosses (MBB 80-133 X H15 L4), (MBB 80-133 X H2L24) and (H2L24 X L35) were found to exhibit high positive specific combining ability effects for number of seeds/pod, seed filling period and seed yield/plot, in the same order. For seed yield/plot the cross (H2L24 X L35) showed positive significant reciprocal effect. The highest value for broad sense heritability was found for number of days to maturity . The mid-parent and better parent heterosis were significant for all the characters. For seed yield/plot, most of the crosses gave more yield than their mid-parent values. The cross (MBB 80-133 X H2L24) showed the highest heterosis over mid and better parents 47.99 and 29.12% , respectively.

EVALUATION OF SOME PROMISING FABA BEAN GENOTYPES (VICIA FABA L.) IN RELATION TO BROOMRAPE (OROBANCHE CRENATA) TOLERANCE. Abdalla, A. F. M. (1) , H. E. Yassien (1) , Sabah. M. Attia, (2) and G. Sh. G. Osman (2) .