In order to determine the effect of different aluminium (Al) concentrations on the seedling parameters of wheat and the effect of malate and citrate treatments as chelates for reducing the noxious effect of Al in medium culture and seedlings of two wheat cultivars, Darab (Al sensitive) and Maroon (Al tolerant) were grown on hydroponic solution (non modified Hoagland) containing AlCl 3 (0-100-200-300 μM). Factorial experiment was realized in a complete randomized design with three replications. The root and shoot length as well as fresh and dry weight of roots and shoots were measured. Leaf area was measured by a special computer program named compuEyeLSA. Analysis of variance (ANOVA) revealed that, for fresh weight of root (FWR), fresh weight of shoot (FWS), dry weight of shoot (DWS) and length of root (LR), the main effect of genotype, Al concentration and their interaction was highly significant, whereas, in the case of dry weight of root (DWR) and leaf area (LA) traits, only the main effect of genotype and Al concentration were highly significant. LS trait only was affected by different Al concentrations. ANOVA indicated a significant interaction between genotype and Al concentration for DWS, FWR, FWS and LR traits. Therefore, a separate regression analysis was conducted for each genotype. We found difference in fitted model between two studied varieties. In the second experiment the effect of malate and citrate treatments was studied on reducing the noxious effect of Al in medium culture. ANOVA revealed that, there are significant differences among applied treatments on studied seedling growth parameters. This means that the application of malate or citrate is effective in some Al concentrations as compared to others.

In order to study the effect of different aluminum (Al) concentrations on the enzyme activities of wheat seedlings and the effect of malate and citrate treatments as chelates for reducing the noxious effect of Al in medium culture, the seedlings of two wheat cultivars, Darab (Al-sensitive) and Maroon (Al-tolerant) were grown on hydroponic solution (non modified Hoagland solution) containing AlCl 3 (0-100-200-300 M). Factorial experiment was realized in a complete randomized design with three replications. The activity of different enzymes such as ascorbate peroxidase (APX), catalase (CAT), glutathione reductase (GR) and superoxide dismutase (SOD) in root and shoot were measured. Analysis of variance revealed that, the activity of studied enzymes (APX, CAT, GR and SOD) in root and shoot were affected by the main effects of Al concentration. However, in the case of catalase activity in root, the main effect of genotypes as well as genotype× × × ×Al concentration was also significant. APX activity in root was not significantly differed between Maroon and Darab in all Al concentrations. But by increasing Al concentration in root medium APX activity was significantly decreased. In the case of SOD activity, we did not find any difference between the studied genotypes in all Al concentrations but its content in roots was affected by the amount of Al applied in medium. So that by increasing the amount of Al, SOD content increased in the genotypes similarly. The same trend was observed for catalase activity in root. In the case of GR activity, we did not find any difference between the genotypes in all Al concentrations but its content in root was affected by applying Al in medium compared with control medium, so that GR content increased in both genotypes similarly. The activity of investigated enzymes showed the same trend in the shoot. The effect of malate and citrate was also studied on reducing the noxious effect of Al in root. Analysis of variance revealed that, there were significant differences within the treatments on the enzymes activity in root (not in the shoot) except for catalase. However, some interaction effects were significant. This means that malate or citrate application was effective in some Al concentrations.

Field experiments were carried out during 2009 and 2010 seasons at three Field Crops Research Stations of (Ismaelia, Sids and New valley). Five different seeding rates were used i.e. 25, 30, 35, 40 and 45 kg/fed and two row spacing i.e. , 30 and 60 cm. Split plot design in three replications are used. The results indicated that sowing at seeding rate of 35 kg/fed with 30 cm row spacing significantly increased all agronomic characters over all cuts and recorded 42.64 t/fed and 8.49 t/fed for total fresh and dry yield, and considered as the best recommended treatment to cowpea under New valley conditions. At Ismaelia conditions, the higher yield was obtained from sowing at seeding rate 45 kg /fed and row spacing of 30 and of 60 cm. Sowing at seeding rate 25 kg/fed with row spacing 30 cm was a perfect treatment for increasing yield. Over two cuts of Sids conditions sowing at seeding rate 30 kg /fed and row spacing 60 cm recorded the best result 15.63, 9.65 t/fed of fresh yield and 1.94, 1.04 t.fed-1 of dry yield for the first and second cuts. The results showed insignificant regression of total fresh yield related to the control was recorded R 2 = 0.2895, R 2 = 0.1888 and R 2 = 0.5822 for New Valley, Ismaelia and Sids, respectively. Chemical composition recorded means of 26.3% soluble carbohydrate, 17.4% crude protein, 21.8% crude fiber and 13.0% ash. Increasing in seeding rates amplified the competition among plants for environmental factors.