Carlos Eduardo Souza Bezerra

Biological aspects of the leafminer Liriomyza sativae (Diptera: Agromyzidae) on melon (Cucumis melo L.)

The leafminer Liriomyza sativae Blanchard is an important insect pest on melon crops in Brazil. However, the information about its biology on melon (Cucumis melo L.) is scarce. Therefore, the aim of this research was to know some biological aspects of this pest, reared on melon plants, under laboratory conditions at 25°C. Our results showed that the biological cycle of L. sativae lasts 15.9±0.04 days (egg-adult), namely: egg (2.7±0.01 days), larva (4.1±0.03 days) and pupa (9.1±0.03 days). The sex ratio is 0.51 and the females live (19.3±1.09 days) longer than males (16.2±0.96 days). These results can help in the integrated management of L. sativae on melon crops and improve the systems for rearing this leafminer in laboratory.

Toxicity of insecticides used in the Brazilian melon crop to the honey bee Apis mellifera under laboratory conditions

This study aimed at evaluating the toxicity of insecticides used in melon crop (Cucumis melo L.) on adults of Apis mellifera L. (Hymenoptera: Apidae) under laboratory conditions. Three ways of exposure were used: direct spraying, feeding with insecticide contaminated diet, and contact with sprayed leaves. Bees were exposed to the insecticides abamectin, acetamiprid, cartap chloride, chlorfenapyr, cyromazin, deltamethrin, thiamethoxam, flufenoxuron, and pyriproxyfen at the highest dosages recommended by the manufacturers for the melon crop in Brazil. Results indicated that, regardless of how the bees were exposed to insecticides, thiamethoxam, abamectin, and chlorfenapyr were extremely toxic to adults of A. mellifera. Acetamiprid, deltamethrin, and cartap chloride were most toxic when directly sprayed on the bees. Cyromazin and pyriproxyfen caused low mortality rates to A. mellifera, whereas flufenoxuron caused moderate mortality when fed to adult bees.

Green lacewings (Neuroptera: Chrysopidae) associated with Melon Crop in Mossoró, Rio Grande do Norte State, Brazil

A survey of the green lacewings associated with the melon agroecosystem was carried out with the aim of including lacewings into the integrated management program of melon pests. Three species of this predator were found: Ceraeochrysa cubana (Hagen), Chrysoperla externa (Hagen) and Chrysoperla genanigra Freitas. A key to these species is presented.

Occurrence of Lysiphlebus testaceipes parasitizing Aphis gossypii in watermelon in the State of Rio Grande do Norte, Brazil

This is the first report of the parasitoid Lysiphlebus testaceipes (Cresson) as a biological control agent of the aphid Aphis gossypii Glover in watermelon crop in Vale do Acu, RN. It was observed that near the harvest, almost all collected aphids were mummified, and after analyzing the emerged parasitoids, the parasitoid L. testaceipes was identified. Therefore, in the future, this species may be included in A. gossypii integrated management programs.