Luciene Xavier de Mesquita

Toxic evaluation in honey bees (Apis mellifera) of pollen from selected plants from the semi-arid region of Brazil.

Summary The toxic potential of Azadirachta indica, Mimosa tenufflora, and Piptadenia stipulacea to honey bees (Apis mellifera) was evaluated. Newly emerged bees were collected and put into wooden boxes that were kept in an acclimatized chamber at 32°C and 70% humidity. Pollen samples were collected from Azadirachta indica, Mimosa tenuiflora, and Piptadenia stipulacea, and were added to food at doses of 0 (control group), 0.25%, 0.5% and 1.0%. Each dose of plant material was fed to 180 bees, and the bees were observed daily until the last one died. Statistical comparison of the survival curves was performed using Kaplan-Meier survival analysis. The pollen of P. stipulacea significantly (P < 0.05) reduced the survival of honey bees, and only slight toxicity of A. indica pollen to honey bees was observed. The differences between the survival curves of bees fed with different doses of M. tenuiflora were not significant (P>0.05). In conclusion, although arthropods may aid the reproduction of plants through the dissemination of reproductive structures, the pollen of some species may be toxic to bees.

Toxidade do Macerado das Flores de Maniçoba (Manihot glaziowii Mull) Fornecido Artificialmente em Condições Controladas para Abelhas

Esta pesquisa foi realizada com o objetivo de avaliar o efeito toxico do macerado das flores de manicoba (Manihot glaziowii Mull), fornecido para abelhas Apis mellifera em condicoes controladas. Cada planta foi pesada em tres fracoes distintas, ou seja, (0,25%, 0,50% e 1,0%) e adicionadas ao “candi” e agua. Para analises dos dados utilizou-se o teste nao-parametrico Log Rank Test, na comparacao das curvas de sobrevivencia. Foi medido o tempo medio de mortalidade e avaliou-se a existencia do efeito toxico do extrato das flores, o tempo medio de mortalidade variou de 14 a 18 dias. Os resultados demonstraram que o extrato de polen dessa flor na concentracao 1,00% proporciona a morte precoce das abelhas operarias. DOI:10.15528/2176-4158/rcpa.v12n1p50-52