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This investigation was carried out at Sakha Agriculture Research Station. Kafer El-Sheikh, Egypt during during 2013/14 and 2014/15 seasons to evaluate thirteen faba bean promising lines under early (mid-October) and late (mid-November) sowing dates comparing with three commercial cultivars. Each sowing date was conducted in a separate replicated complete blocks experiment and combined analysis was done over both sowing dates and growing seasons to study the effect of genotype x environment interaction on heritability and genetic advance for seed yield and some related traits. Highly significant mean squares of seasons were detected for all studied traits. Sowing dates and genotypes mean squares were highly significant for all traits tested. Mean squares of sowing date x season interactions were highly significant for chocolate spot reaction, No. of seeds/plant and seed yield /plant. Highly significant mean squares of the interactions between genotypes and seasons were found for chocolate spot, No. of pods and seeds/plant, 100-seed weight and seed yield /plant. The interactions between genotypes and sowing dates were highly significant for maturity date, no. of seeds/plant and seed yield/plant. The highest values of predicted genetic advance were mainly due to high vales of heritability and the latest was coupled with high phenotypic coefficient of variability.

Half diallel cross among ten yellow maize inbred lines was made at Sakha Agriculture Research Station during the growing season 2015. The resultant 45 crosses along with two commercial hybrids as yellow checks (single crosses 162 and 168) were evaluated at two field experiments in two years 2016 and 2017. The results indicated that, years (Y) mean squares had significant effects for all traits, except resistance to downy mildew disease. Genotypes (G) and crosses (Cr) mean squares had high significant effects for all traits in the two years and its combined data. However, G x Y and Cr x Y interaction were significant or highly significant for all traits. Mean squares due to general combining ability (GCA) and specific combining ability (SCA) were highly significant for all traits in the two years and their combined analysis. On the other side, the interactions between GCA and SCA with years were highly significant for all traits. For GCA / SCA and GCA x Y / SCA x Y mean squares ratio, the data pointed out that, this ratio exceeded the unity for all studied traits in two years and their combined. The inbred line P4 had desirable significant of (g^i) for earliness, good plant type, resistance to downy mildew and late wilt diseases, also the inbred line P8 had desirable significant of (g^i) for earliness and good plant type. The single crosses; P1 x P3, P6 x P7 and P4 x P5 had negative and significant values of (s^ij) for good plant type and earliness. The single crosses P1 x P2,

Three field experiments were carried out at Sakha Agricultural Research Station Farm, Kafer El-Sheikh Governorate, ARC, Egypt, during three successive winter seasons of 2008/09, 2009/10 and 2010/11, to investigate the performance of some egyption clover genotype for its resistance/tolerance to dodder infestation. Anatomical structures as well as biochemical analyses for berseem plants were carried out to identify variation in the correlated traits with tolerance to dodder infestation. The results indicated that genotypes no. 35 and 65 showed that the moderate genotypes behaved different, the parasite is scarcely able to pierce the epidermis but lignifications of host pericycle and starch sheath showed incompatible interaction between clover genotypes and C. planiflora. The sensitive genotypes no. 29 and 94 were in contrast compatible with the parasite, the infection developed normally with the intrusive cells reaching the center cylinder and the host vascular tissues. The results indicated that the amount of phenolic acids is relatively high; 1111.65 and 965.24 g/100 mg of foliage dry weight for genotypes; Helali and no. 51, respectively. These two genotypes could retain some tolerance to the infestation with C. planiflora. Whereas, the phenolic acids in the genotypes no. 35 and 74 which are considered to some extent retain moderate tolerance to infestation with dodder were present in lesser concentration (784.6 and 735.38 g/100 mg). While, Genotypes no. 94 and 29 which could be considered susceptible to infestation with dodder, phenolic acids were found in trace amounts (386.64 and 423.02 g/100 mg), respectively. HPLC analysis revealed the presence of protocatechuic acid, caffeic acid, P-hydroxyl benzoic acid, coumaric acid, ferulic acid, vanllic acid and syringic acid and their concentrations were different from berseem genotype to another. The obtained results may be encouraging to use the tolerant genotypes, which had the least reduction percentages due to dodder infestation, for developing compost or synthetic cultivar(s) which retain tolerance to dodder infestation. This cultivar could be used by itself as a way of control of dodder in farmers' fields or integrated with the other factors of dodder control.