Bioecologia e controle biológico da Cochonilha-rosada em Roraima

Abstract

The pink hibiscus mealybug, Maconellicoccus hirsutus (Hemiptera: Pseudococcidae), is a pest recently introduced in Brazil threatens numerous crops, especially to orchards and ornamental plants. The first reported of this pest in Brazil was in Roraima, and there was not information about its bioecology and biological control in the country. The objective of this work was to study the biology and the population dynamic of M. hirsutus and of its natural enemies in Roraima. The work was conducted in the laboratory to determine the biological parameters of M. hirsutus and in an orchard of Annona squamosa L. (Anonaceae), to evaluate the effect of the climate, biological control and crop management on its dynamic population. Maconellicoccus hirsutus can have up to nine generations per year, with 6.5 days to double their population size. The number of females is about three times larger than that of males. The oviposition was 98 eggs / female, with viability of 97%. Populations of M. hirsutus were higher during the period of fruiting and it did not correlate with climate variables. The infestation levels were low (5.2%) and can be related to high parasitism rates (55.4%) by por Anagyrus kamali Moursi (Hymenoptera: Encyrtidae) and predation by lacewing (Chrysopidae). Pruned trees were less infested 40.95% lower than those trees not pruned. Maconellicoccus hirsutus has a high biotic potential in dry and warm weather conditions, however its natural enemies associated to a good management practices can maintain the population levels of M. hirsutus low.