Reproduction in 2 biotypes ofSchizaphis graminum(Rondani) were compared under a controlled environment. Biotypes B and C were compared when both apterous and alate virginopara served as parents. Aphids were reared on winter wheat seedlings under simulated fall growing conditions of 17.2°C temp and a photoperiod of 12 h. Both biotypes produced approximately the same number of progeny, and within a biotype the ratio of winged to wingless offspring remaind parallel for both apterous and alate parents. However, biotype C produced approximately 25% alate offspring, as opposed to 1% for biotype B during the same period.