CERTAIN ECOLOGICAL ASPECTS FOR Icerya seychellarum (Westwood) ON COFFEE PLANTS Coffea arabica IN EGYPT

Abstract

Certain ecological aspects of the Seychellarum mealybug, Icerya seychellarum (Westwood) which is considered as a key pest on coffee trees, a promising newly crop cultivated in Egypt, have been investigated under two different ecosystems throughout two years, 2009 & 2011. Results revealed that this mealybug species was found all the year round in both localities. The total population recorded four peaks of seasonal abundance in both investigated ecosystems on coffee trees and it passed through three overlapping generations in both ecosystems. The main weather factors, four weeks earlier, showed miscellaneous effects on the population dynamics of this mealybug species. Means of minimum and maximum temperature had a positive significant effect; while mean percentage of relative humidity showed insignificant effect in the two localities. The combined effects of the four weather factors, as a group, had significant effects on I. seychellarum population throughout both years. In Qalyubyia Governorate (2009), the percentage of explained variance was 56.8%; while in Giza Governorate (2011), this value was 65.9%.

Population Density of the Striped Mealybug Ferrisia virgata (Ckll.) (Hemiptera: Pseudococcidae) on the Ornamental Corn Shrubs, Dracena fragrans in Relation to Biotic and Abiotic Factors in Al-Zohria Gardens, Cairo, Egypt

“…On the other hand, the relative humidity gave an insignificant positive effect during the fall, winter and summer. Many authors showed the same effects of meteorological parameters on the population activities of mealybugs, Nabil, et al, (2013) and Raut, et al, (2013).…”