Estudo de Chrysoperla externa (Neuroptera: Chrysopidae) no controle de pragas em roseiras em cultivo protegido e biologia de Macrosiphum euphorbiae (Hemiptera: Aphididae)

Abstract

This study was conducted aiming at obtaining information about the ability to control pests in rose through the release of eggs and larvae of first, second and third instar of Chrysoperla externa (Hagen, 1861) in protected cultivation. Experiments aimed to reduce the populations of mites, aphids and whiteflies, and to evaluate the effect of different temperatures on the development of the aphid Macrosiphum euphorbiae (Thomas, 1878) that, especially in a protected environment, constitutes an important pest in rose cultivation. In the first experiment, two experimental sites were separated and, in the first, we adopted the conventional control by using phytosanitary products, and in the second, releases of eggs and larvae of C. externa in the three instars were performed. The efficiency of C. externa and predators found in the experiment was evidenced by a decrease in population density of these arthropods that infest the rose plants.. In the second experiment, the experimental area was divided in half and in one half, three lines were sown with the green manure calopogonium between the rows of rose plants. The impacts of the association calopogonium were evaluated for biological control of pests on roses. This interaction was positive, because it reduced the occurrence of M. euphorbiae by approximately 50% compared to the area without this association. In the third experiment, using a fertility life table, we evaluated the effect of constant temperatures in the survival and reproduction of M. euphorbiae in rose leaves. Tests were conducted in climatic chambers at 17; 22; 25 and 28 ± 2 °C, RH 70 ± 10% and photoperiod of 12 h. At 17ºC, this species had the lowest survival rate. The longevity, specific fertility and average total fecundity occurred at 25 °C, indicating that this temperature is the most suitable for the development of M. euphorbiae in rose plants.