Abundance and diurnal rhythm of honeybees visiting hybrid seed production plots of cauliflower (Brassica oleracea var. botrytis L.).

摘要

The abundance and diurnal rhythm of honey bees on parental lines were studied in hybrid seed production plots of cauliflower in Karnal, Haryana, India, from 2001 to 2002 and 2002 to 2003. In both years, different Apis species were the predominant pollinators with A. dorsata being the most abundant. Pollen gatherers outnumbered nectar collectors. Bee foraging populations were significantly different among sowing dates in both years. Honey bee foraging activity was found to be highest between 12:00 to 14:00 h, and bees preferred to visit parental lines. A. florea spent more time per flower and plant than other species. A. dorsata visited more flowers per minute followed by A. florea. Honey bees spent more time per flower and plant and carried more pollen on their bodies in the morning than afternoon. Among bees, A. dorsata carried more pollen on its body. Flower nectar volume ( micro litre) was higher in mornings and nectar sugar content higher in the afternoons. There was no significant variation in parental lines with regard to nectar volume. Nectar sugar content differed significantly between parental lines during 2001-2002. The female line had more nectar sugar content than the male line. Bee activity was positively correlated with temperature, light and nectar sugar in both years. But relative humidity, wind velocity and nectar volume negatively correlated with bee activity..