LATENT EFFECTS OF SOME PESTICIDES an‎d PLANT GROWTH REGULATOR ON COWPEA APHID, Aphis craccivora KOCH (HOMOPTERA: APHIDIDAE)

The latent toxicity of chemical insecticide; malathion, bioinsecticide; Beauveria bassiana and a plant growth regulator (PGR) Extratone were studied on some biological parameters of adult Aphis craccivora under laboratory conditions. The obtained results revealed that the two sub-lethal concentration 0.01 and 0.1 ppm sub LC50 (0.73 ppm) of malathion decreased each of the mean longevity of adult (one day old), mean offspring in addition to pre-parturition, parturition and post- parturition periods in comparison to the control. Eventually, both concentrations reduced the mean numbers of offspring of adult per day. B. bassiana at concentrations (200ppm) at (100ppm) decreased each of the mean longevity of adult, number of offspring, pre-parturition and parturition but increased post-parturition periods in comparison to the control. Both concentrations of B. bassiana treatment reduced the mean number of offspring of A. craccivora (one day old) during longevity per day. Extratone at recommended concentration decreased the duration of A. craccivora, increased the pre-parturition period and decreased the parturition period, Post- parturition period, the mean longevity of A. craccivora and the mean number of offspring of each A. craccivora adult female.