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Abstract ”Survey the main insect pests attacking potato plants and their natural insects. Total numbers and percentages of the main insect pests attacking summer plantation during the two successive seasons 2017 and 2018 at Meniat El-naser, Dakhlia Governorate can be seen that there were five insect species belonging to order Hemiptera, these species were Bemisia tabaci (Gennandius), Myzus persicae(Sulker), Empoasca descipiens, Empoasca lybica,de berg and Aphis gossypii Glover. Five insect species from order Lepidoptera were recorded these species namely: Phthorimia operculella (Zeller); Tuta abslauta ; Euzophora osseatella Treitske, Spodoptera exigua (Hb.) and Spodoptera littoralis(Boisd.). Four predators species belonging to Family Coccinellidae order Coleoptera these predators namely: Hippodamia trideciapunctata, Coccinella undicimpunitata, Chilomenes propinqua isis and Chilomenes propinqua nilotica , and one predator specie from family chrysopidae , order Neuroptera was recorded. And one parasitoid specie from order Diptera was found. It can be stated from these tables that most dominant species were Hippodamiatridecimpunctata and Coccinella undicimpunitata. at 31th of March (82 indiv. / 100 leaflets) in 2018 seasons. The population density then decreased gradually to reach its minimum at the end of the seasons. The relation between temperature parameters and the population size of this insect cleared significant positive correlation during the two seasons of study, meanwhile, the effect of relative humidity exerted varied values ranged from slight to insignificant correlation during the period of study. The values of proportional effect (explain variance) of temperature ranged between 27% to 29% and the relative humidity ranged 11% to 12% during the two seasons of study. The weekly catch of A. gossypii cleared that the population density started early at the time of plant sprouting that started by low population and fluctuated till the first week of March and recorded one peak at 7th of April (38 indiv. / 100 leaflets) in 2017 seasons. The population density then decreased gradually to reach its minimum at the end of the seasons. Meanwhile, the effect of relative humidity exerted varied values ranged from slight to insignificant correlation during the period of study. The values of proportional effect (explain variance) of temperature ranged between 36% to 40% and the relative humidity ranged 16% to 18% during the two seasons of study. The weekly catch of E. descipiens revealed that the population density started early at the time of plant sprouting that started by low population and fluctuated till the first week of March and recorded two peaks at 17th of March (32 indiv. / 100 leaflets) and 14th of April (36 indiv. / 100 leaflets) in 2017 seasons. The population density then decreased gradually to reach its minimum at the end of the seasons. The effect of relative humidity exerted varied values ranged from slight to insignificant correlation during the period of study. The values of proportional effect (explain variance) of temperature ranged between 17% to 26% and the relative humidity ranged 14% to 19% during the two seasons of study. The obtained results showed that the population density of E. lybica population density started by low population and fluctuated till the first week of March and recorded two peaks at 10th of March (22 indiv. / 100 leaflets) and 14th of May (31 indiv. / 100 leaflets) in 2017 seasons. The population density. |