Study of the Bioecology of Aleurolobus olivinus Silvestri (1911) (Homoptera, Aleyrodidae) on olive Trees in Algeria

Abstract

Aleurolobus olivinus is an insect of the family Aleyrodidae and the subfamily Aleyrodinae, considered as a secondary pest of olive trees, Olea europea, and has also been reported on Phillyrea angustifolia, P. latifolia and on Erica spp. It consists of a bio-ecological study, in particular of the life cycle that has been carried out on the branches of trees covered with a fine mesh net to avoid possible exchanges of individuals, while for the ecological study, leaf samples have been taken according to cardinal directions and branches 50 cm long according to their age, on 4 varieties of olive tree. The black whitefly generates two generations, one from April to September and the other from October to March. The life cycle lasts 79 to 98 days. Larvae mainly prefer the upper surface of the foliage in the South and Estet are abundant in autumn and winter and the varieties Zaiti (33.3%) and Sorani (27.4%) are the most infested compared to Terella and Khodeiri (21.8%) and (17.4%). It is the twigs of the year that are most attacked. The parasitism rate varies according to the month and season, it is 17% in autumn and 7.6% in winter while the monthly rate is 6% in May and 21.5% in November.