A green house experiment was carried out in two successive seasons on date Palm plantlets (Phoenix dactylifera L. cv. Bartomouda) from 2012 to 2013, to evaluated the effectiveness of different sources of nitrogen fertilizer at four treatments as (T2) 5 g/l ammonium sulfate 20 % (1 g nitrogen), (T3) 3 g/l potassium nitrate 33% (1 g nitrogen) and (T4) 2 g/l urea (46%) with the irrigation water one time/ week.The design of the experiment was randomized complete with three replicates. The results revealed that, plant height cm, leaves numbers, root length cm and numbers, and fresh and dry weights of leaves and roots were increasing highly significantly with 3 g/l of potassium nitrate graduated by 2 g/l urea and 5 g/l ammonium sulfate respectively at both seasons. Chlorophyll a, b and carotenoids contents showed significant rising with 3 g/l potassium nitrate. Greatest significant contents of indole and proline were obtained under T3 for two seasons. Leaves nitrogen content N was increased by 2 g/l urea in the two seasons; on the other hand, root nitrogen content was increased with treatment 3 g/l potassium nitrate, sequenced by T2 and T4 treatments. Leaves and roots phosphorus P content significantly raising under 3g/l potassium nitrate and 5 g/l ammonium sulfate for two seasons. In the presence of 5 g/l ammonium sulfate and 3 g/l potassium nitrate leaves and root potassium content K were largest at two seasons respectively. This research shows that the nitrogen formula as potassium nitrate > ammonium sulfate > urea were recommended to highly increasing growth of date palm plantlets in the green house.

The potato plants (Solanum tuberosum L.) vs. valor were exposed to different levels of nitrogen fertilizer (60, 100, 140, 180 kg N/feddan (4200 m2)) and in-row plant spacing (12.5, 25 and 50 cm) for maximizing the yield production to match food security needs under climate change impacts on Delta region,  Egypt. The experiment was carried out during two growing seasons (2010/2011 and 2011/2012) in split plot design at El-Bossily Farm, Agricultural Research Center, El-Behira Governorate, Egypt. The vegetative growth characteristics and yield parameters were measured. The result of this study verified that increasing nitrogen level up to 180 kg N/feddan significantly increased the vegetative growth, total and marketable yields than the other N treatments. The in-row plant spacing 50 cm was significantly increased vegetative growth and yield (kg/plant), but the total yield (kg/m2) had different trend. The highest total yield /m2 was obtained by 12.5 cm treatment. The interaction effect of 180 kg/feddan of N and 12.5cm in-row plant spacing were increased the total tuber yield (kg/m2) significantly. In contrary, the best marketable yield (tubers > 35 mm) /m2 was obtained by 25 and 50 cm in-row plants.  This study was concluded that the best agronomic practices for potato production obtained by application 180 kg N/feddan of with in-row plant spacing 25 cm treatment. The economical consideration of the different treatments showed that the best total net income was obtained by 180 kg/feddan N with 50 cm in-row plant spacing.