Relative Abundance of Different <i>Apis</i> spp. On Rapeseed-Mustard

Abstract

Abundance of insect pollinators on rapeseed-mustard showed that bees were most abundant on Brassica rapa L. var. toria i.e. 15.15, 18.47, 21.02 and 15.11 bees/ m2 / 10 min and least abundant on Brassica nigra i.e. 8.43, 9.53, 11.30 and 8.47 bees/ m2 / 10 min at 1000 h, 1200 h, 1400 h and 1600 h, respectively. At 1000 h, Apis mellifera was observed as the most abundant pollinator (13.94 bees/ m2 / 10 min) followed by A. cerana (11.23 bees/ m2 / 10 min), A. dorsata (10.50 bees/ m2 / 10 min) and A. florea (8.30 bees/ m2 / 10 min) and the same trend was also followed at 1200 h, 1400 h and 1600 h. The comparative mean abundance of Apis spp. on different varieties/ genotypes of rapeseed-mustard revealed that bees were most abundant on variety TH 68 (16.77 bees/ m2 / 10 min) and least abundant on Nigra (9.12 bees/ m2 / 10 min). Also A. mellifera had maximum (15.50 bees/ m2 / 10 min) mean comparative density across the varieties/genotypes followed by A. cerana (12.90 bees/ m2 / 10 min), A. dorsata (12.25 bees/ m2 / 10 min) and A. florea (9.37 bees/ m2 / 10 min). The activity of different honey bees varied with time i.e. maximum abundance of A. mellifera, A. cerana, A. dorsata and A. florea was reported at 1200 to 1400 h and it was least abundant at 1000 h and 1600 h of the day.