Sex determination in bees. XXVII. Castes obtained from larvae fed homogenized food in Melipona compressipes (Hymenoptera, Apidae)

Abstract - One hundred and eighty-three larvae of Melipona compressipes were fed with mixed food collected from 391 cells containing eggs of various ages. Nine recently provisioned cells had an average of 238 mg of food; the maximum quantity of food a cell can receive if completely full averages 308 mg. Larvae were reared in wax cups receiving 350, 300 and 240 mg of food (control). Death rate was high due to the handling of larvae. In the 350 mg group, 17 workers and 4 queens were obtained and 34 died before the pupal stage. In the 300 mg group, 39 workers and 8 queens pupated and 38 died. In all there were 56 workers and 12 queens. If quality of food were decisive in queen determination, no segregation of queens and workers should occur, as the food was a homogenized mixture. Weight of last larval stage and genetics were the preponderant caste determinants. Below 184.7 mg of last larval weight no queens are produced; above it, a 3 workers to one queen segregation was observed; we therefore conclude that genetics is the ultimate determining factor of caste in Melipona.