The effects of climate and bee race on Varroa jacobsoni Oud infestations in BrazilG. Morettoa, L.S. Gonçalvesb, D. De Jonga and M.Z. Bichuettec
a University of São Paulo, Faculty of Medicine, Genetics Department, Riberão Preto-SP, Brazil
b University of São Paulo, Faculty of Philosophy, Sciences and Letters, Biology Department, Riberão Preto-SP, Brazil
c University of São Paulo, Faculty of Philosophy, Sciences and Letters, Department of Geology Ribeirão Preto Campus, 14 049 Ribeirão Preto, SP, Brazil
Abstract - Varroa jacobsoni infestation rates on adult Africanized and Italian/Africanized hybrid honey bees were measured in 3 different climatic regions of Brazil : Ribeirão Preto, Rio do Sul and São Joaquim (mean temperatures 21, 18 and 13 °C, respectively), over a 2-yr period. The mean infestation rates were 3.5, 5.11 and 11.37 mites per 100 bees in the 3 regions respectively, demonstrating that climate type has a strong influence and that infestation rates are higher in the cooler regions. The type of bee also had an important effect, as the Italian hybrids were significantly more infested than the Africanized bees (7.53 and 5.78 mites per 100 bees, respectively).
Key words: Varroa jacobsoni / infestation rate / Africanized honeybee / climate