REPRODUCTIVE POTENTIAL OF LABORATORY-REARED MANDUCA SEXTA (LEPIDOPTERA: SPHINGIDAE) AS AFFECTED BY SEX RATIO

Abstract
The influence of sex ratio on the reproductive ability of the tobacco hornworm, Manduca sexta, was examined under laboratory controlled conditions. The optimum sex ratio was found to be 0.50 (F/T) displaying the highest rate of oviposition and egg production. The fertility of the eggs laid was linearly dependent on the number of males present in each ratio. Unmated females lived longer and began oviposition later than mated females. The percentage of the total egg production retained by the females was highest for the 0.17 and 0.83 ratios and may be attributed to a stress-related impairment of reproductive behaviour.