الفهرس 
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Abstract
The aim of this investigation was to study the effect of soil ap-plication of nitrogen and potassium at increased levels along with the foliarapplication of a fertilizer solution on the growth and the bio-chemical content of moringa plants grown under irrigation with saline water “salinity stress conditions” in two successive seasons with the aim of attain the highest yield of moringa leaves and seeds and bio-chemical contents with the best fertilizer use efficiency, especially under saline stress conditions, and to define the most appropriate N and K rate. To fulfill the aim of the study, a field experiment was carried out for two seasons 2013 and 2014 at El Sheikh Zoweid Research Station of the DRC, North Sinai, Egypt of the indices 31.0 14’ 9.8” N, 34.0 6’ 54.4” E and elevated by 25 m above sea level.
The design of the experiment was a spilt-split design in rando-mized, complete blocks involved three factors with three replicates as follows:
Factor A: Nitrogen fertilizer at four levels
Factor B: K fertilizer at four levels
Factor C: Foliar fertilization at two rates as follows:F0 = Without foliar applicationF = With foliar application
The main plot was assigned to foliar application; non-foliar vs. foliar application of a mineral fertilizers solution. The sub plot was potassium fertilizer applied at four levels i.e. 50, 100, 150 and 200 kg K ha-1 as potassium sulfate (41.5% K). The sub-sub plot was nitrogen fertilizer applied at four levels i.e. 120, 240, 360 and 480 kg N ha-1 as urea (46% N).
Sixty-four, one year old, moringa shrubs (Moringa oleifera) were planted at space of 1.5×1.5m (2.25 m2/shrub) at a rate of two shrubs per replicate. Both soil and foliar applications of fertilizer were applied at three doses during the different stages of moringa growth i.e. vegetative, flowering and fruiting stages. Phosphorus was applied at one rate (22 g P/shrub) as calcium super phosphate (6.8% P) at the beginning of the growth season. Organic manure was applied at a rate of 1.25 kg com-post/shrub mixed with the applied calcium super phosphate.
Irrigation was done using saline well water of EC of 5.09 dS m-1 and 6.24 dS m-1 in first and the second season, respectively.
Four levels of nitrogen applied as urea form and four levels of potassium applied as potassium sulfate were combined in sixteen combined treatments. All sixteen combinations were applied to plants via soil without or with foliar application of a nutrient solution containing 5234, 4313, 5786, 595, 595, 595 mg L-1 (1428 L ha-1) of N, P, K, Fe, Mn, Zn, respectively.
The obtained results could be summarized as follows:
1. All of the studied growth parameters of moringa plant (shrub height, the number of branches/shrub, leaves/branch and the number of pods/branch) significantly increased with increasing the level of the N and K fertilizers applied to the soil in the both seasons of study. The highest values of these parameters was obtained due to the soil application of N and K at the highest level (480 kg N ha-1 and 200 kg K ha-1).
2. Leaves yield and pods yield increased with increasing the level of the applied N and K fertilizers with the highest increase at the highest level of application (480 kg N ha-1) in the both seasons of study. This may be due to that the applied N and K provide a nutrient balance for the growing plants which has been reflected on their growth and showed better growth parameters, nutrients uptake and biochemical contents of moringa plants especially in the 2nd season
3. Moringa plants responded positively to the soil and foliar fertilizers application especially when applied together more than when applied individually in the both seasons.
4. Integration between foliar application of a fertilizer solution and the soil application of N and K fertilizers was more effective in increasing yield parameters, nutrient uptake than the soil application only; this pattern occurred in the both seasons. This could be attributed to the relatively high supplying power of the integration fertilization.
5. The more effective treatment was the soil application of K4N4 with the foliar application of the fertilizer solution where it gave 10.98, 55.22, 1.43 and 0.69 Mg ha-1 for leaves, pods, seeds and oil, respectively in 1st season, and 15.68, 67.4, 1.69 and 0.83 Mg ha-1 in 2nd season.
6. The soil application of K4N4 with the foliar application treatment was more effective in increasing nutrients uptake by leaves and seeds, in the 2nd season compared with the same treatment in 1st season. The magnitudes of increase in nutrients uptake were 40.2 and 27.8 % for N, 39.4 and 28.2 % for P, 47 and 36.2 % for K, 40.7 and 28.5 % for Fe, 40.6 and 28.3 % for Mn, 48.8 and 28.7 % for Zn and 47.1 and 35.5 % for Cu in the leaves and seeds of moringa plant, respectively.
7.The most effective treatment in increasing the biochemical contents of moringa plants was (K4N4+foliar application) which showed higher increases in moringa biochemical contents in the 2nd season than the same treatment in 1st season. The increase was by 17.6, 16.7, 17.1, 17.4, 14.6, 14.7, 19.8, 19.7, 18.9 and 18.7% for total chlorophyll, beta carotene, carbohydrate in leave, carbohydrate in pods, protein in leaves, total antioxidants in leaves, total antioxidants in pods, total phenol in leaves and total phenol in pods, respectively.
8.The integration fertilizati method was recommended to be used as approach to increase the yield and the biochemical contents of moringa plants growing under salinity stress conditions