ZOUBIR, SOUADILIAS, FAIZA2024-12-102024-12-102023http://dspace.univ-temouchent.edu.dz/handle/123456789/5773The objective of this study, conducted in the region of Aïn Témouchent (Algeria), in three citrus farms, is to determine the diversity and abundance of scale insects. The infestation carried out between March 5 and June 1, 2023 revealed the presence of two species of scale insects: Parlatoria ziziphi and Planococcus citri belonging to two main families: Diaspididae and Pseudococcidae. The family Diaspididae is dominant in terms of species, with two species present. The results of this study indicate that Parlatoria ziziphi (Diaspididae) is the most widespread species in the three citrus plots. However, parasitism, predation, and mortality play crucial roles in regulating scale insect individuals. Based on the study of the distribution of scale insect infestation, we can conclude that these pests are mainly active on the leaves, especially on the upper part of them, rather than on the branches. With regard to orientation, scale insects show a very marked preference for the first two farms studied among the three plots studied.frAgrumes, Cochenilles, infestation, vergerCitrus, Mealybugs, leaves, infestation, orchardThesis