16 research outputs found
Immature stages of Spodoptera albula (Walker) (Lepidoptera: Noctuidae): Developmental parameters and host plants
Seletividade de inseticidas, recomendados para cucurbitåceas para Trichogramma atopovirilia Oatman & Platner (Hymenoptera: Trichogrammatidae) em condiçÔes de laboratório
As brocas-das-cucurbitĂĄceas Diaphania spp. sĂŁo as principais pragas das cucurbitĂĄceas, podendo ocasionar perdas de atĂ© 100% na produção. A fim de reduzir o uso de inseticidas, o controle biolĂłgico, aplicado com parasitoides do gĂȘnero Trichogramma, tem-se destacado. Objetivou-se avaliar a seletividade dos ingredientes ativos abamectina, tiacloprido e clorfenapir, para Trichogramma atopovirilia Oatman & Platner (Hymenoptera: Trichogrammatidae). Para isso, 20 fĂȘmeas recĂ©m-emergidas de T. atopovirilla foram individualizadas, em tubos de vidro (2,5 cm de diĂąmetro x 8,5 cm de comprimento), e oferecidas cartelas com 30 ovos de Diaphania hyalinata (Linnaeus) (Lepidoptera: Pyralidae), previamente imersas por cinco segundos em calda quĂmica. Os ingredientes ativos abamectina, tiacloprido e clorfenapir nĂŁo afetaram o parasitismo de T. atopovirilia. Clorfenapir reduziu a emergĂȘncia. Abamectina e tiacloprido sĂŁo os mais recomendados no manejo integrado de pragas, pois foram os que se mostraram mais seletivos a T. atopovirilia em ovos de D. hyalinata
Ação residual de agrotóxicos pulverizados em plantas de milho sobre Trichogramma pretiosum
Performance of Nellore heifers, forage mass, and structural and nutritional characteristics of Brachiaria brizantha grass in integrated production systems
A glyphosate-based herbicide in a free-choice test on parasitism, emergence, and female-biased sex ratio of 10 Trichogrammatidae
Lethal and Sublethal Effects of Insecticides Used on Citrus, on the Ectoparasitoid Tamarixia radiata
Huanglongbing (HLB) is a disease associated with the bacteria "Candidatus Liberibacter spp." and has been devastating citrus orchards around the world. Its management involves control of the insect vector, the Asian citrus psyllid Diaphorina citri Kuwayama. However, the indiscriminate use of chemicals has caused pest outbreaks and eliminated the natural enemies of the vector, such as the parasitoid Tamarixia radiata (Waterston), the main agent for biological control of D. citri. This study assessed the lethal and sublethal effects of insecticides recommended for integrated production of citrus on the parasitoid T. radiata. When adult parasitoids were exposed to residues of 25 insecticides, 20% of them, i.e., gamma-cyhalothrin, etofenprox, azadirachtin, tebufenozide and pyriproxyfen, were considered as harmless (Class 1), 12% as slightly harmful (Class 2), 12% as moderately harmful (Class 3) and 56% as harmful (Class 4), according to the classification proposed by the IOBC/WPRS. Afterward, 14 insecticides (5 harmless and 9 harmful) were sprayed on the parasitoid pupae. Of the 14 insecticides tested, only the organophosphates dimethoate and chlorpyrifos affected the parasitoid emergence. The effects of insecticides on the parasitism capacity of adults exposed to residues of azadirachtin, etofenprox, gamma-cyhalothrin, pyriproxyfen and tebufenozide (harmless) were also evaluated. Tebufenozide and gamma-cyhalothrin affected the parasitism of the F0 generation, but did not affect the emergence of the F1 and F2 generations. Therefore, for an effective IPM program, selective insecticides or harmful pesticides to adult parasitoids could be used in the field, provided that the adults do not occur naturally and the chemical applications do not coincide with parasitoid releases