Dwarf cashew antibiotic and antixenotic resistance to the whitefly aleurodicus cocois

Abstract

The aim of the present study was to identify Aleurodicus cocois resistant genotypes among five dwarf cashew clones available in the germplasm bank of Embrapa/ Centro Nacional de Pesquisa Agroindústria Tropical. Free-choice and no-choice tests were applied in order to evaluate the relative attractiveness of the clones and the oviposition preferences, egg-to-adult development times and adult emergence rates of the pest. In comparison with other clones, PRO143/7 exhibited the lowest attraction to the whitefly and was least preferred for oviposition in the free-choice test. Conversely, CCP76 attracted the highest number of A. cocois and was preferred for oviposition. In the no-choice test, the rates of emergence of adults from clones BRS274, CCP76 and PRO143/7 varied between 53.0 and 56.8%, values that were significantly lower (p < 0.05) than those of clones BRS226 and EMBRAPA51, which were 72.34 and 75.16%, respectively. Some of the cashew clones tested showed antibiotic (CCP76, PRO143/7 and BRS274) and antixenotic (PRO143/7 and BRS226) resistance to A. cocois. These clones are good candidates for use in breeding programs of cashew.