In Brazil, the ectoparasitic mite of bees Varroa destructor Anderson and Trueman (Acari: Varroidae) remains at low levels of infestation causing no major damage. However, with the introduction and possible dominance of a new haplotype (K) of the mite, usually found in areas with high infestation rates (IR), it is necessary to monitor and select beehives that are resistant to the pest in order to avoid future problems. Several factors are listed as potentially being responsible for the dynamics of mite infestation, among which hygienic behavior (HB) stands out. In this context we sought to evaluate the HB of Africanized honey bees Apis mellifera L. (Hymenoptera: Apidae) compared with the mite IR in apiaries of two municipalities of southeastern Brazil (Taubaté and Viçosa). For the municipality of Taubaté, the average IR was 4.9% (3.4 to 5.8%), while the HB averaged 98.6% (96 to 100%). In Viçosa, the average mite IR was found to be 10.0% (5.4 to 21.0%) with an average value for HB of 57.7% (0 to 79.0%). Results from this research show that IR and HB were negatively correlated (R = -0.9627, P<0.01), suggesting that hives with higher HB have lower IR.Keywords: Acari, Apidae, bee pathology, pest management, Varroidae RESUMO No Brasil, o ácaro ectoparasita de abelhas Varroa destructor Anderson e Trueman (Acari: Varroidae) se mantém em índices de infestação baixos, não causando grandes prejuízos. Todavia com a introdução e possível predominância de um novo haplótipo (K) do ácaro, geralmente encontrado em regiões com altas taxas de infestação (TI), faz-se necessário o monitoramento e seleção de colônias resistentes à praga, evitando problemas futuros. Vários fatores são relacionados como possíveis responsáveis pela dinâmica de infestação do ácaro, dentre os quais se destaca o comportamento higiênico (CH). Nesse contexto buscamos avaliar o CH de abelhas africanizadas

Helicoverpa armigera, one of the world’s most destructive crop pests, was first documented in Brazil in 2013. Within a few months, this polyphagous insect had spread over the Northeast and Central-West of Brazil, causing great agricultural losses. With several reports of populations resistant to pesticides and Bt crops around the world, there is great concern about the spread of this pest in Brazil. There is confusion about the actual distribution of this species due to the high morphological similarity with the native corn earworm Helicoverpa zea, which may also coexist with H. armigera in the field. Our aims here were (i) to confirm its presence in the State of Minas Gerais, one of the most important agricultural regions in the country; and (ii) to assess the co-occurrence of this pest with the congeneric corn earworm H. zea. Using molecular screening, we confirmed the presence of H. armigera in Bt-crops of soybean and cotton, and non-Bt-crops of soybean, cotton and maize. Mixed infestations of H. armigera with H. zea were found in non-Bt maize (Viçosa, Southeastern Minas Gerais). These results highlight the need for adequate control strategies for H. armigera in Brazil, to deal with its polyphagous feeding habits, high dispersal capacity and possible risks of hybridization with congeneric species.

Communication

The mite Varroa destructor is one of the most studied parasites in apiculture, and its genotype variation is a key factor for the severity of infestation in bee colonies. Here we report the genetic and reproductive profile of mites from 14 Brazilian states with different geographic and climatic conditions. We performed PCR to amplify a fragment of the COI gene and differentiate the haplotypes using restriction enzymes. The K haplotype was widely prevalent in the studied sites, while the J haplotype was found only in four municipalities. We also observed both haplotypes (J and K) coexisting in the same colony, a fact unprecedented in Brazil. Infestation levels were low (0.33 to 15.3%). The reproductive potential showed wide variation (0 to 1.5), indicating that even with the massive presence of K haplotype, environmental and biotic factors related to Africanized honeybees may be responsible for maintaining the mite under low levels in Brazil.