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EntomoBrasilis 7 (1): 05-11 (2014) EcologiaResumo. O objetivo do presente estudo foi avaliar a influência dos fatores abióticos na dinâmica populacional da mosca-branca Bemisia tabaci (Genn.,) (Hemiptera: Aleyrodidae) em três épocas de semeadura de feijoeiro (Phaseolus vulgaris L.). Os ensaios foram instalados de junho de 2010 a abril de 2012, todos conduzidos no Departamento de Fitossanidade da FCAV/UNESP -Campus de Jaboticabal, SP. Os estudos de dinâmica populacional de B. tabaci biótipo B, foram obtidos através da avaliação semanal da infestação de ovos, ninfas e adultos de mosca-branca por 18 avaliações, sendo seis para cada época de semeadura: "de inverno", "das águas" e "da seca", respectivamente, além da influência dos fatores abióticos, temperatura e umidade relativa (mínima, média e máxima) semanal e precipitação pluviométrica acumulada, sendo essas variáveis correlacionadas com o número total de ovos, ninfas e adultos de mosca-branca através de uma análise do tipo correlação linear de Pearson (r). Dentre os resultados obtidos, destaca-se que os picos populacionais de B. tabaci biótipo B ocorreram na semeadura "das águas", seguido pelas semeaduras "de inverno" e "da seca" e que os fatores abióticos temperatura e umidade relativa influenciaram negativamente na dinâmica populacional de mosca-branca. Palavras-Chave: Infestação; Fatores abióticos; Phaseolus vulgaris. Population Dynamics of the Whitefly Bemisia tabaci (Genn.) Biotype B (Hemiptera: Aleyrodidae) on Bean PlantsAbstract. This study aimed to evaluate the influence of abiotic factors on the population dynamics of the whitefly Bemisia tabaci (Genn.,) (Hemiptera: Aleyrodidae) in three sowing seasons on bean plants (Phaseolus vulgaris L.). The assays were set up from June 2010 to April 2012 and conducted in the Departamento de Fitossanidade at FCAV/UNESP -Campus of Jaboticabal, SP. The studies of the population dynamics of B. tabaci biotype B were performed weekly through infestation assessments of eggs, nymphs and adults of the whitefly on 18 samplings, six for each sowing season: "winter", "water" and "dry", in addition to the influence of the abiotic factors weekly temperature and relative humidity (minimum, average and maximum) and accumulated rainfall. These variables were correlated to the total number of eggs, nymphs and adults of the whitefly through Pearson's linear correlation analysis. Among the obtained results, the population peaks of B. tabaci biotype B occurred at the "water" season, followed by "winter" and "dry" seasons, and the abiotic factors temperature and relative humidity influenced negatively the population dynamics of the whitefly.

h i g h l i g h t s Resistant plant genotypes may affect natural enemies directly and indirectly. Resistant tomato plants directly affected P. nigrispinus development and behavior. The negative effects were associated with density and types of glandular trichomes. Using P. nigrispinus and resistant tomato could be antagonistic for T. absoluta control.

ANÁLISE ESPACIAL DA MOSCA-NEGRA-DOS-CITROS EM POMAR DE CITROS UTILIZANDO A GEOESTATÍSTICA

Whitefly Bemisia tabaci (Gennadius) biotype B is the major pest of common bean (Phaseolus vulgaris L.) in Brazil and other countries. Host plant resistance is one of the cornerstones of Integrated Pest Management (IPM), and assessment of cultivars for insect resistance is fundamental to provide farmers options for pest control. This study evaluated common bean resistance to whitefly in the winter and rainy seasons in Jaboticabal, Brazil, and correlated the infestation with climatic factors. The plant part and development period of common bean that are more susceptible to whitefly infestation were also examined for potential use in IPM. Field experiments were carried out using 18 and 19 commercial cultivars in the winter and rainy seasons, respectively. Whitefly eggs, nymphs, and adults in the upper part and lower part of plants were sampled from 25 to 60 days after emergence (DAE). Cultivars IAC-Una and IAC-Eldorado had less oviposition and the former also showed lower adult infestation in the winter season. In the rainy season, cultivars IAPAR-81 and Guará had a smaller number of eggs, whereas IAC-Centauro was less infested by nymphs. The number of nymphs and adults was similar among cultivars in the winter and rainy seasons, respectively. The upper part of plants had a greater number of eggs and adults, while, the lower part harbored larger numbers of nymphs. Common bean was more susceptible to whitefly at 25-32 DAE in both seasons. These results add useful information to IPM of whitefly in common bean.