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The present studies were carried out to survey and evaluate the population densities of some insect pests infesting rosemary plants and their associated predators during the two successive seasons of 2013 and 2014 at Abo-Kabir district , Sharkia Governorate. The obtained results are summarized as follow : Seven insect species belonging to seven families and four orders were recorded as insect pests on rosemary plants. Bemisia tabaci (Genn.), Aphis gossypii Glover, Empoasca decipiens (Paoli) and Thrips tabaci Lind. were the most dominant species and recorded 53.95, 19.01, 13.08 and 8.14 % of the total insects numbers, respectively.Bemesia tabaci showed four peaks on 1 st August , 22 nd August , 19 th September and 17 th October in the first season and on 24 th July , 21 st August , 2 nd October and 20 th November in the second one. A.gossypii had two peaks on 1 st August and 29 th August in the first season and three peaks on 7 th August , 4 th September and 25 th September in the second season .Temperature and relative humidity influenced B.tabaci populations by 4.4337 and 72.9724 % in the first and second seasons , respectively. Temperature and relative humidity affected A. gossypii population by 33.91 and 44.68 % during the two successive seasons , respectively .Five predaceous insect species belonging to five families and four orders were surveyed. Paederus alfierii (Koch), Coccinella undecimpunctata L. and Chrysoperla carnea (Steph.) were the most dominant species inhabiting rosemary plants and representing 52.12, 24.00 and 10.35% of the total number of predators, respectively.

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These studies were carried out in El-Mansoura district, Dakahlia Governorate during the two seasons of 2004/2005 and 2005/2006 on different citrus trees (Navel orange, Mandalin and Valencia orange). The present study illustrated that Aphis gossypii Glover, Aphis citricola (V.D. Goot) had two peaks at April and August during the two seasons of investigation. While, Myzus persicae (Sulzer) and Aphis craccivora Koch had one peak occurred during March and April for the two seasons. Each aphid species showed different degrees of preference for the different tested citrus trees. A. gossypii exhibited higher population on Mandarin trees. While Navel orange receive the highest population of A. citricola and M. persicae. The weather factors play a great role on the population density and seasonal abundance of the tested aphid species.