Bombus ssp. (Hymenoptera: Apidae) as pollinators of male-sterile upland cotton on the Texas high plains

A study was conducted to investigate the importance and potential use of Bombus as cotton pollen vectors on the Texas High Plains. A survey of 13 counties showed that Bombus pennsylvanicus (DeGeer) was the predominant species. Bumble bees visited cotton flowers throughout the blooming season, and they foraged for both nectar and pollen. More foragers were present on MS than isoline male-fertile (MF) flowers, but visitation to the MS flowers was restricted primarily to morning hours. Nectar and pollen foragers collected in MF flowers carried large amounts of cotton pollen on their body (5,586 to 16,235 grains per forager).