International Union for the Study of Social Insects (IUSSI2018), August 5-10, 2018 in Guarujá, Brazil.

only days left!
Find us: Ft

Irreversible worker sterility in a stingless bee: ovary structure and oogenesis in Tetragonula carbonaria

Author(s):
Francisco Garcia Bulle Bueno, Francisco Garcia Bulle Bueno , Ros Gloag , Tanya Latty , Isobel Ronai
Institution(s):
School of Life and Environmental Sciences, University of Sydney, Sydney, Australia; School of Life and Environmental Sciences, University of Sydney, Sydney, Australia ; School of Life and Environmental Sciences, University of Sydney, Sydney, Australia ; School of Life and Environmental Sciences, University of Sydney, Sydney, Australia ; School of Life and Environmental Sciences, University of Sydney, Sydney, Australia
The productivity of a social insect colony is dependant on the workers being non-reproductive and the queen being fertile. In some species, workers remain capable of laying unfertilised eggs that produce males, while in other species worker sterility is absolute. Workers of the Australian stingless bee Tetragonula carbonaria possess regressed ovaries but do not lay eggs in queenless colonies. We tested whether or not T. carbonaria’s workers’ ovaries can be rescued in a controlled microcolony with no queen and where they are fed a highly nutritious diet (honey bee royal jelly). We also examined the ovary structure of T. carbonaria mature workers, newly emerged virgin queens, and mature queens. T. carbonaria possess four ovarioles per ovary, typical of stingless bees. While the ovaries of the mature queens are activated the ovaries of the virgin queens are semi-activated (no mature oocytes). We found that the ovaries of the queenless workers fed royal jelly are degenerated with only the basal end of a few of the ovarioles observable which means that the degeneration must occur prior to adulthood. Our results suggest that T. carbonaria workers are completely and irreversibly sterile. T. carbonaria may have evolved absolute worker sterility because colonies are rarely without a queen; queens are reared constantly in large numbers and excess queens killed. Our study is the first test of irreversible sterility in the stingless bees from the Australasian region. 
Back