الفهرس 
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Abstract
Ecological studies: Survey of important insect pests on pomegranate trees and their associated predators: .Insect pests:Thirteen insect pests were surveyed on pomegranate trees during the two successive studied seasons, 2006 and 2007.These insects were A. punicae, A. citri, A. aurantii, C. ficus, I. seychellarum, P. citri, S. phillyreae, C. capitata, N. viridula, E. lybica, O. hylinipennis, S. livipens and C. carinulata. The highest percentage of occurrence was the pomegranate whitefly S. phillyreae (73.8 and 76.3% of total insect pests on pomegranate trees leaves, followed by A. punicae (18.81 and 16.44%), I. seychellarum (4.42 and 3.99%) and A. citri (2.61 and 2.85%) during the two successive seasons 2006 and 2007, respectively. On the other hand, the lowest percentage of occurrence was C. ficus (0.04 and 0.07%) followed by P. citri (0.15 and 0.09%) and A. aurantii (0.15 and 0.25%) during the two successive seasons 2006 and 2007, respectively. Insect predators: Thirteen insect predators were found associated with insect pests attacking pomegranate trees during 2006 and 2007 seasons. The highest abundant insect predators during two successive seasons inhabiting pomegranate trees was S. interruptus followed C. arcuatus, S. syriacus, Orius spp. C. vicina isis and P. alfierii. On the other hand, the lowest predators abundant were H. trideampuncata (0.13 and 0.23%) followed by R. litura (0.13 and 0.38%), Syrphus spp. (0.27 and 0.53) and C. carnea (0.54 and 0.62%) from the total predators during the two successive seasons (2006 and 2007), respectively. Population abundance of the main insect pests attacking pomegranate trees and their associated predators: Insect pests: The pomegranate whitefly, S. phillyreae eggs had two peaks of abundance in both seasons of the study with an average number of 462.1± 169.3 and 509.1± 155.5 eggs/280 pomegranate leaves during the two successive seasons 2006 and 2007, respectively. The pomegranate whitefly S. phillyreae larvae had two peaks of abundance in both seasons of study with an average numbers 211.7 ± 78.0 and 269.3 ±72.0 larvae/280 leaves during the two successive seasons 2006 and 2007, respectively. The pomegranate whitefly S. phillyreae pupae had two peaks of abundance in both seasons with an average number of 140.6 ±45.4 and 208.7± 55.3 pupae/280 leaves during the two successive seasons 2006 and 2007, respectively. The pomegranate aphid, A. punicae had four peaks of abundance in both seasons 2006 and 2007 with an average 121.3 ± 26.1 and 118.4 ± 26.0 individuals /280 leaves during the two successive seasons, respectively The mealybug I. seychellarum had three peaks in season 2006 and two peaks in 2007 season with an average number of 29.1±4.4 and 28.8±4.6 individuals /280 leaves during the two successive seasons 2006 and 2007, respectively. The pentatomid bug N. viridula was appeared in April in both studied seasons 2006 and 2007 with the highest average numbers 15.5 and 32.0 insects/100 double strokes occurred in June in both seasons of study. The general average was 4.9±4.2 and 8.2±4.3 individuals /100 double strokes. The E. lybica was peaked two times during every seasons (2006 and 2007) with an average number 60.3±53.0 and 47.6±17.3 individuals /100 stroks during the two successive seasons 2006 and 2007, respectively. Insect predators: The highest abundant predator on pomegranate trees was S. interruptus with an average number of 46.5±12.5 individuals/10 double strokes followed by C. arcuatus 13.2±3.2; S. syriacus 12.5±2.2; Orius spp. 7.8±2.6, and C. vicina isis 3.8±1.3 individuals/100 double strokes. On the other hand, the lowest abundant predator were C. vicina nilotica with an average number of 0.5±0.2 individuals/100 strokes followed by C. savignii 0.9±0.4 individuals./100 strokes and R. cardinalis 1.0±0.4 individuals/100 strokes during 2006 season. The results in season 2007 approximately in same trend of these in the first season (2006) where the predator S. interruptus had the highest abundant with an average number 35.7±10.9 individuals/100 strokes followed by C. arcuatus 15.1±3.1; S. syriacus 7.6±1.4; Orius spp. 4.7±1.3; P. alfierii 2.9±0.8 and C. vicina isis 2.5±0.7 ind. /100 double strokes, respectively. On the other hand, the lowest abundant predators were C. vicina nilotica; R. cardinalis; C. savignii and C. carnea with an average number of 0.7±0.4; 0.8±0.5; 1.2±0.3 and 1.2±0.4 ind/100 strokes, respectively. Influence of different directions of the pomegranate trees on the main insect pests: The highest average numbers of S. phillyreae eggs were recorded in the east direction and represented by 59.8±27.3 and 101.0±34.0 eggs/40 leaves, followed by the north direction 58.1 ± 21.9 and 83.8±28.7 eggs/40 leaves, the south direction 56.0±21.8 and 63.6±20.0 eggs/40 leaves and the west direction 38.8±17.3 and 34.6±17.7 eggs/40 leaves during the two successive seasons 2006 and 2007, respectively. Statistical analysis revealed that, a highly significant differences were recorded between the west direction and the another three directions during the first season 2006 and showed a highly significant differences between the four directions during the second season according to the average number of insect eggs. The highest average numbers of S. phillyreae larvae occurred in east direction with average numbers of 45.6 ± 11.9 and 58.2 ± 16.4 larvae/40 leaves in 2006 and 2007, respectively followed by 31.6 ± 13.8 and 52.8 ± 15.7 larvae/40 leaves in north in 2006 and 2007, respectively. On the other hand, the lowest average number was recorded in west and south directions and represented by (17.4 ± 7.2, 23.4 ± 11.4) and (23.1 ± 6.5 and 47.8 ± 15.5) larvae/40 leaves during the two successive seasons (2006 and 2007), respectively. The highest average number of I. seychellarum was 4.7±1.1 individuals/ 40 leaves in north direction during the first season, while it was 12.8 ± 2.6 indiv./40 leaves in east direction during the second season. Statistical analysis showed that, a highly significant differences were recorded between the different directions according to the average number of I. seychellarum during the two seasons of the study. Influence of different levels of pomegranate trees on the main insect pests: The lower level received the highest number of S. phillyreae eggs and the highest peak was recorded in October during the two successive seasons, 2006 and 2007 with an average number 188.6 ±74.6 and 170.8 ± 52.5 eggs/40 leaves, respectively. On the other hand, the upper level received the lowest number of eggs with an average number of 8.2 ± 4.4 and 6.6 ± 3.6 eggs/40 leaves, respectively. The differences among average numbers of eggs according to the levels of pomegranate trees were found highly significant differences. The highest average numbers of the insect pupae occurred in the lower level and represented by 44.2 ± 12.8 and 41.3 ± 9.5 pupae/40 leaves during 2006 and 2007, respectively followed by the middle level with an average number of 19.4 ± 9.4 and 15.2 ± 4.8 pupae/40 leaves, respectively. Statistical analysis showed that, the differences among average numbers of pupae were highly significant differences in the three levels during the two seasons. Efficiency of the parasitoid E. inaron on the pomegranate whitefly, S. phillyreae larvae and pupae in different directions and levels of pomegranate trees The highest average percentage of parasitism caused by the parasitoid E. inaron were recorded in south direction 16.6 ±5.1% followed by north direction 13.6± 2.8%, west direction 7.6± 1.7% and east direction 7.6± 2.1% during season 2006. In 2007 season, the highest average percentage of parasitism was in west direction and represented by 13.8± 2.9% followed by north, south and east directions and represented by 13.1± 3.7, 9.1± 2.8 and 8.1± 2.0%, respectively.