The seasonal activity of the peach twig borer, Anarsia lineatella Zeller was in-vestigated during 2004 and 2005 seasons. The data revealed that the infested twigs empty from larvae (15%) were higher than that with larvae (1.25%) in February. The situation was reverse in April which recorded 8% and 14.75% for both, respec-tively. In fruits, infestation began to appear in the third week of March which rec-orded 2% whereas the maximum rate was recorded in May (16.75%). Three species of hymenopterous parasitoids were found; Apanteles ruficrus Haliday (Fam. Braco-nidae), Diplazon laetatorus Fab. (Fam. Ichneumonidae) and Microgaster tiro Rein-hard (Fam. Braconidae). These parasitoids reached its maximum during April (13.5%) that seems to be more active. Their numbers were positively correlated with the rate of infestation (r = + 0.799). In spite of presence of four predatory species (Coccinella undecimpunctata L., Rodalia cardinalis Mulsant, and Scymnus syriacus Marseul (Coleoptera: Coccinellidae) and Syrphus sp. (Diptera: Syrphidae)), it seems to be less active. Their numbers recorded very slight positive correlation with the rate of infestation (r =+0.423)

The present work was carried out to study the population dynamics of the mealy plum aphid Hyalopterus pruni (Geoff.) and related parasitoids and predators on apricot trees, during the two successive seasons, 2003 and 2004, at Qalubia Gover-norate. The obtained data revealed that, the occurrence of H. pruni on apricot trees covered 5 months (from February to June). The mean total numbers of this aphid species per season were 1.78 (0.01-6.37) and 2.83 (0.00-10.01) individuals./leaf. The maximum numbers of H. pruni were recorded during the 2nd weeks of April, 2003 and 2004. No aphid individuals were observed during the period extended from July to September, in the two studied seasons. Four species of parasitoids; namely Aphidius matricariae Hal., Lysiphylbus sp. (1ry parasitoids) and 2 species of Alloxysta spp. (2ry parasitoids) were recorded during this study, attacking H. pruni. These parasitoid species were found during nearly three months of each season, in connection with the population density of the previous aphid species. The first para-sitoid was the highest in its numbers. The total numbers of predatory species per season were 407 and 1082 individuals, in the two studied seasons, 2003 and 2004, respectively. The maximum monthly occurrence of these predatory species was dur-ing April, 2003 (146 individuals) and April, 2004 (581 individuals), respectively. The predator Chrysoperla septempunctata L. had the highest percentages of occur-rence among other recorded predatory species (52.83 and 73.01%, respectively). In general, the parasitoid A. matricariae and the predator C. septempunctata, could be mass reared and released for controlling H. pruni on apricot trees with other availa-ble safe control methods developed in Integrated Pest Management (IPM) programs against this pest.

Field studies were carried out to study the effect of the different four directions (East, West, North and South) and the middle of the orange trees on the occurrence of the citrus leafminer, Phyllocnistis citrella Staint. (Lepidoptera: Gracillariidae), attacking orange orchards during the period extended from the beginning of July, 2015 until the end of June 2016. Also, to determine the common predatory species occurred in navel orange orchards in Qaluobiya Governorate. The warmer months that have the highest temperature degrees and that months having the newly orange leaves, had the highest percentages of infestation by the pest. The obtained results revealed that, the South direction of the orange trees had the highest percentages of leaves damage by the citrus leafminer, P. citrella. Where, there were significant differences between the South direction (68.75%), in comparing with those of the West direction (64.42%), the North direction (60.58%), the East direction (54.58%) and the middle of the orange trees (45.38%). So, it is recommended to firstly begin the Integrated Pest Management (IPM) programs against the pest in this direction and at the suitable time. Moreover, the importance of the natural role of the common predatory species recorded in the orange orchard is obviously shown and must be encouraged and developed. The highest total numbers of all recorded predatory species were during July, 2015 (47 individuals) and April, 2016 (35 individuals). The recorded predatory species were the highest in the South direction (70 individuals), in comparing with those of the North direction (54), the East direction (50), the West direction (37) and the middle of the orange trees (20). True spiders were recorded as the most predators (114 individuals), in orange orchard and also in the same time of pest occurrence. The animal predatory species (true spiders and predatory mites) were the highest in their numbers (167 individuals), in comparing to the insect predatory species: Chrysoperla carnea, Scymnus sp., Coccinella undecimpunctata, Orius sp. and Metasyrphus sp., of lower individuals numbers (64 individuals). In general, from this study, it is also recommended to use the different predatory species such as: Chrysoperla carnea, Scymnus sp., Coccinella undecimpunctata and Orius sp., for P. citrella control firstlyfrom the South direction. Where, this pest controlcan be applied by mass rearing of these predators in the laboratory and releasing them in orange orchards against P. citrella or other related pests (such as the citrus aphids species and mealybugs). This approach is believed to be highly practical for use as one of the means of biological control with the frame work of suitable and safe IPM programs in citrus orchards in Egypt.