Life spans of Africanized honey bees fed sucrose diets enhanced with citric acid or lemon juice

Abstract

The maintenance of laboratory confined bees is a growing need for several entomological studies. Improving laboratory conditions, e.g., diet, to allow greater longevity to individuals is a desirable outcome for insects maintained under those conditions. We evaluated the life span of confined Africanized bee “workers” fed with an aqueous solution obtained from acidic hydrolysis of sucrose. We ran two experiments simultaneously and had a single control treatment. In the first one, the bees were fed 100 g of sucrose solution (1:1) enhanced with 0.1, 0.16, 0.3, 0.5 and 0.7 g of citric acid. The second experiment was conducted using an aqueous solution of granulated (1:1) enriched with 1.0, 5.0, 10.0, 15.0 and 20.0 ml of lemon juice from Citrus aurantifolia (C.) Swingle, Citrus latifolia Tanaka and Citrus limonia (L.) Osbeck at in each solution. We arranged ten repetitions with ten bees each. The number of surviving bees was counted every 12 h, during daytime, for 192 h total. The survival curve was adjusted using Weibull’s model we calculated the values for LT10, LT20, LT50 and LT99. Considering the relevance of an artificial diet to feed and maintain bee colonies, we concluded that adding citric acid at amounts lower than 0.3 g for each 100 g of sucrose may increase the lifespan of Africanized worker bees confined in laboratory, through providing partially inverted food. If lemon juice is used as a substitute for the citric acid, the amount should be less than 10 ml for each 100 g of sucrose.