الفهرس 
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Abstract
The aim of this research was to study the effect of three sources from mineral nitrogen fertilizers (S1= ammonium sulfate (20.5%), S2= ammonium nitrate (33.5%) and S3=urea (46%)) on Growth and Leaf Mineral Content of Young Trees of “Wonderful”, Pomegranate. The experiment included three rates of mineral nitrogen (R1=70, R2=140 and R3= 210g N /tree / year). The study is a factorial experiment in a randomized complete block design (RCBD),the experiment contains nine treatments, each contains four replicates and the replicate represented by two young trees .the obtained results could be summarized as follows:-
1- Effect on Vegetative growth:
In both the two seasons, the first source S1(ammonium sulfate) gave the highest significant values of leaf area, shoots number, shoot length and % dry matter of wood, whileS1(ammonium sulfate) and S2(ammonium nitrate )gave the highest significant values of %dry matter of leaves. On the other hand, the second source S2 (ammonium nitrate) gave the highest significant values of total chlorophyll in leaves, in both the two seasons, also the third source S3 (urea) gave the highest significant values of stem diameter, in both the two seasons.
With respect to nitrogen rates, it was observed that fertilizing by the first rate of nitrogen R1(70g N /tree / year) gave the highest significant values of stem diameter , % dry matter of wood and % dry matter of leaves in both the two seasons ,also shoots number and shoot length in the first season .Found that fertilizing by the second rate of nitrogen R2(140g N /tree / year) gave the highest significant values of leaf area in both the seasons and shoots number and shoot length in the second season . While that fertilizing by the first rate of nitrogen R3 (210g N /tree / year) gave the highest significant values of total chlorophyll in leaves, in the second season.
Regarding the interaction, treatment (S1R1) gave the highest significant values of stem diameter and shoot length in the first season and % dry matter of leaves in both the two seasons .While that treatment (S1R2) gave the highest significant values of leaf area, shoots number and % dry matter of wood in both the two seasons, also shoot length in the second season. Treatment (S2R2) gave the highest significant values of stem diameter in the second season, while treatment (S2R3) gave the highest significant values of total chlorophyll in leaves, in both the two seasons.
2- Effect on mineral Content:
Generally in both the two seasons, the first source S1(ammonium sulfate) gave the highest significant values of phosphorus, potassium, calcium, iron and zinc content, In addition to carbohydrate content in the wood and C:N ratio in the wood . While the first source S1 (ammonium sulfate) and the second source S2(ammonium nitrate)gave the highest significant values of nitrogen content , in both the two seasons. The third source S3 (urea) gave the highest significant values of sodium and manganese content, in both the two seasons.
Regarding nitrogen rates, it was observed that fertilizing by the first rate of nitrogen R1(70g N /tree / year) gave the highest significant values of nitrogen ,phosphorus, iron content, In addition to carbohydrate content in the wood and C:N ratio in the wood ,in both the two seasons .Also nitrogen content in the wood , in the second season .Found that fertilizing by the second rate of nitrogen R2(140g N /tree / year) gave the highest significant values of calcium and zinc content, in both the two seasons, in addition to manganese content, in the first season. While that fertilizing by the third rate of nitrogen R3(210g N /tree / year) gave the highest significant values of manganese content in the second season, in addition to nitrogen content in the wood, in the first season.
Concerning the interaction, treatment (S1R1) gave the highest significant values of nitrogen content, in both the two seasons. While it gave the highest significant values of phosphorus, potassium, iron and zinc content, In addition to carbohydrate content in the wood and C: N ratio in the wood , in the first season. However treatment (S1R2) gave the highest significant values of calcium content, in both the two seasons. While it gave the highest significant values of phosphorus, potassium, sodium and zinc content, In addition to carbohydrate content in the wood and C: N ratio in the wood, in the two season .Treatment (S1R3) gave the highest significant values of iron content, in the second season. Whereas treatment (S2R1) gave the highest significant values of nitrogen content in the wood, in both the two seasons’ .Meanwhile treatment (S3R2) gave the highest significant values of sodium content in the first season. Finally the treatment (S3R3) gave the highest significant values of manganese content, in both the two seasons.