A field experiment was carried out on sandy soil of the Agricultural Research Experimental Station, at Ismailia Governorate (latitude 30º 35ʹ 41.9ʺ N and longitude 32º 16ʹ 48.8ʺ E), Egypt, during two successive growing summer seasons; 2013 and 2014. The study aimed to investigate the effect of applying three levels of water supplied through sprinkler irrigation system representing; 100 %, 75 % and 50 % of water supply which corresponding to 2500, 1875 and 1250 m 3 fed-1 , on the forage yield productivity and quality of fodder cowpea. Such levels represented commonly practiced irrigation (control), moderate and severe water deficit stress for fodder cowpea, respectively. Also, to evaluate the role of four rates of potassium sulphate fertilization namely, 24, 36, 48 and 60 K2O kg fed-1 in alleviating the adverse effect of water deficit stress on cowpea plants under these conditions. Three cuts were taken throughout the growth season. The obtained results revealed that decreasing the levels of water from 100% to 75 or 50% level markedly reduced all traits under studied; plant height, leaves number per plant, leaves/stem ratio of cowpea, green and dry forage yield (kg fed-1), at the three cuts as well as the total yield of the three cuts. The reduction noticeably appeared more detrimental under 50% of water stress especially at the 3 rd cut. The results showed that the total green and dry forage yield of the three cuts of plants treated with 48 kg K2O fed-1 , under 50% irrigation level, reduced by 52.4 % and 57.0 %, respectively; compared with the yields obtained by plants received the recommended K rate (48 kg K2O fed-1) under commonly practiced irrigation. Increasing water deficit stress lowered carbohydrate %, crude proteins % and ash content (kg fed-1) in plants as well as K% in leaves. Also, it significantly decreased the contents of Fe, Zn and Mn in plants. Increasing the application rates of K up to 60 K2O kg fed-1 substantially elevated all the aforementioned studied traits under each level of irrigation and the reduction resulted due to water stress, under 75% and 50% levels could be suppressed. Application of the highest K rate (60 K2O kg fed-1) not only considerably heightened all the detected nutrients; carbohydrate % and proteins %, ash and micronutrients (Fe, Zn and Mn) uptake by plants as well as K% in leaves of cowpea, but also it remarkably enhanced the water use efficiency by plants grown under 75% irrigation than all applied K rates treatments under 100% irrigation. From the obtained results, it could be inferred that under moderate water stress 75% of the commonly practiced irrigation application of 60 K2O kg fed-1 could sustain cowpea plant to grow satisfactorily.

Two field experiments were conducted at Ismailia Agricultural Research Station during two successive summer seasons of 2010 and 2011. The response of pearl millet cultivar (Shandaweel-1) grown under sandy soil conditions to different mineral N fertilization rates (60, 90 and 120 kg N fed -1 ) and foliar application of chelated-EDTA micronutrients (Fe + Mn + Zn) at rates of 0.0, 0.2, 0.4 and 0.6 g l -1(400 l fed -1 ) on growth characters, productivity, and some nutrient contents, were appraised. Such response was followed up through three cuts; at 45, 85, and 125 days from complete emergence of the seedlings. The obtained results reveal that plant height, number of tillers per plant and productivity of pearl millet; fresh forage and dry matter yields of the three cuts at the both seasons, were enhanced by increasing the application rate of N fertilization. Foliar application of micronutrients markedly augmented such parameters. The best results were obtained when applying 120 kg N fed -1 accompanied with micronutrient foliar application of either 0.4 or 0. 6 g l -1 . Carbohydrate, protein and crude fiber contents (%) of the dry matter of pearl millet plants were remarkably raised due to increasing rates of both; N fertilization and foliar micronutrients. Moreover, the uptake of N, P, K (kg fed -1 ) and uptake of Fe, Mn and Zn (g fed -1 ) by millet plants were elevated. Focusing on the necessity of growing pearl millet as a prosperous summer forage crop in Egypt was speculated.

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