Impacto dos inseticidas clorfenapir e metamidofós sobre a comunidade de artrópodes do feijoeiro

• Autor(a) principal: Barros, Emerson Cristi de
• Data de Publicação: 2006
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/951
• topic: Entomofauna; Metamidofós; Clorfenapir; Feijão; Inseticidas; Principal componente de análise; Entomofauna; Metamidofós; Clorfenapir; Beans; Insecticides; CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOSSANIDADE::ENTOMOLOGIA AGRICOLA

This work aimed to study the impact of the insecticides chlorfenapyr and methamidophos on arthropods community of the bean crops with one and two applications. This experiment was carried out on commercial beans farming placed in Coimbra city, Minas Gerais state, Brazil during period from March until June, 2005. The treatments were established in factorial arrangement 2 x 2 (insecticides x number of applications) and control (no application). The Randomized Block Design was used with five replications. The arthropods phytophagous, predators, parasitoids and soil-dwelling on the plant canopy, soil surface and soil interior were evaluated. The arthropods community one day before application and 1, 8, 16, 24, 32, 40 and 48 days after the application of the treatments were sampled. The first application of the treatments was in 04/30/2005 and the second application after three weeks was done. The dosage used on treatments were 0,18 L a.i/ha and 0,45 L a.i/ha respectively. The arthropods associates to the plant canopy, were sampled by beating a white plastic tray in the apex of five bean plants. The arthropods community from the soil surface were sampled by pitfall traps. Also were sampled the population of arthropods of the soil interior, being these samples collected by removing of soil blocks with approximately 30 cm of depth and 10 cm of diameter and then submitted to the funnels of Berleze. The set of were submitted to the canonical variate analysis, Mahalanobis Distance statistic and multivariate analysis by repeated measures. The main insects associates to the canopy of the bean crops affected to clorfenapir and methamidophos are the phytophagous pests Cerotoma arcuata (Coleptera: Chrysomelidae) and Caliothrips phaseoli (Thysanoptera: Thripidae). Chlorfenapyr and methamidophos reduced the attack of C. arcuata and C. phaseoli to the bean plant up to 16 days after application. The main arthropods on the soil surface affected by clorfenapir and methamidophos are the soil-dwelling Isotoma sp., Emtomobryidae (Collembola) and Scheloribatidae (Acari). Chlorfenapyr and methamidophos reduced the populations of the soil-dwelling Isotoma sp., Emtomobryidae and Scheloribatidae on the soil surface. The main arthropods in the soil interior affected by clorfenapir and methamidophos are the soil-dwelling Hypogastrura sp. (Collembola), Galumnidae sp.1, Scheloribatidae (Acari) and the predator Hypoaspis sp. (Acari). Chlorfenapyr and methamidophos reduced the populations of the soil-dwelling Hypogastrura sp., Galumnidae sp.1 and Scheloribatidae and of the predator Hypoaspis sp. A fast recovery of this arthropods densities associated to the canopy plant and soil surface were observed after the insecticides applications. However after the second application of the methamidophos, was not observed to the recovery of the arthropods density until to the end of experiment.