Assessing Bemisia tabaci (Genn.) biotype b resistance in soybean genotypes: Antixenosis and antibiosis.

José Paulo Gonçalves Franco da Silva1*, Edson Luiz Lopes Baldin1, Efrain Santana de Souza1, André Luiz Lourenção2

Since it was first reported in Brazil in the 1990s, the B biotype of silverleaf whitefly (Bemisia tabaci [Genn.], Hemiptera: Aleyrodidae) has been recognized as an important pest in soybeans (Glycine max L.), reducing the productivity of this legume species in some areas of the country. As an alternative to chemical control, the use of resistant genotypes represents an important tool for integrated pest management (IPM). This study evaluated the performance of 10 soybean genotypes prior to whitefly infestation, by testing attractiveness and preference for oviposition in the greenhouse and antibiosis in the laboratory. In a multiple-choice test, ‘IAC-17’ was the least attractive to insects. In a no-choice test, ‘IAC-17’ was the least attractive for egg deposition, indicating the occurrence of non-preference for oviposition on this genotype. Trichome density was positively correlated with the oviposition site and may be associated with the resistance of ‘IAC-17’ to infestation. The genotypes ‘IAC-PL1’, ‘IAC-19’, ‘Conquista’, ‘IAC-24’ and ‘IAC-17’ extended the insect’s life cycle, indicating the occurrence of a small degree of antibiosis and/or non-preference for feeding.

Keywords: Glycine max, silverleaf whitefly, host plant resistance, attractiveness, non-preference, trichome.
1Universidade de São Paulo, Facultade de Ciencias Agronómicas, Botucatu, São Paulo, Brasil. *Corresponding author (jpgfdsilva@gmail.com).
2Instituto Agronomico de Campinas, Centro de Pesquisa e Desenvolvimento de Fitossanidade, Entomologia, Campinas, São Paulo, Brasil.