Role of photoperiodism in the developmental cycle of bumble bees (Hymenoptera, Bombidae) . Preliminary communication
Grinfel' d, E.K.; Zakharova, L.V.
Vestnik Leningradskogo Gosudarstvennogo Universiteta Biologii 9(2): 149-150
In studies made in midsummer, artificial shortening of hours of daylight to 12 h for a B. hortorum colony and to 12.5 h for a B. pascuorum (= B. agrorum) colony caused an acceleration of the development cycle in both colonies. The first stage, the formation of males and females, proceeded normally, but the second intermediate stage, the development of large workers, did not occur.