Influence of ultraviolet radiation and temperature on the phototactic response of tropical species of stingless bees

Abstract

Abstract We evaluated how ultraviolet (UV) and green light in the solar spectrum, as well as temperature, affected the proportion and latency of phototactic choice for three distinct stingless bee species within a Y-shaped maze. We showed that all studied bee species chose the edges with a higher incidence of solar UV light more often and with shorter choice latencies than other edges. Under conditions of low UV at both ends of the maze, neither a higher proportion of green nor a higher total light intensity impacted the phototactic orientation of bees towards a particular maze arm. The proportion of choice in Frieseomelitta varia did not change in response to an increase in temperature, and remained high with increased UV light. These results indicate that UV light was an important component of the phototactic response of the tropical bee species studied, and this should be considered when using them to provide pollination services in environments with a low incidence of UV light, as is prevalent in greenhouses. Moreover, the phototactic behaviour observed in F. varia, even under heat stress conditions, suggested that this species was suitable for use as pollinators in greenhouses.