Responses of multiple generations of Spodoptera littoralis feeding on gossypol

One of our objectives in this investigation is to determine responses of S. littoralis through different developmental stages and generations to secondary metabolic compound presumably gossypol. Gossypol did not significantly show antifeedant except with high concentration (1.7% gossypol in the diet) that gave 10.6, 21.9, and 46.8% for three generations, respectively. Significantly longer larval life-spans were observed in S. littoralis on a high concentration of gossypol compared with those fed on low concentrations. The larval and pupal weight of the third generation was significantly lower than that of the previous two generations as latent effects on survived larvae significantly lower fecundity was found in the second and third generations. A significantly lower relative growth rate was observed in the three successive generations. Generally, the efficiency of gossypol was significantly higher in the second and third generations. Gossypol significantly affected growth and development, suggesting that diet-gossypol efficiency was different based on concentration and generation. This study will shed some light on the possibility of controlling S. littoralis by gossypol through the sequence of alternative spraying programs.