Effect of mayonnaise and emulsifiable concentrate formulations on population dynamic of greanhouse whitefly (Trialeurodes vaporariorum)

The greenhouse whitefly, Trialeurodes vaporariorum Westwood, is one of the most important pests in the world and Iran, which causes great damage to agricultural products annually. In this study, the effect of 50% lethal concentration (LC50) of mayonnaise and emulsifiable concentrate (EC) formulation (50 ml/lit) on life-table parameters of greenhouse whitefly was investigated using leaf-deaping method under laboratory conditions. The experiment was performed on second nymphs instar. The lowest number of eggs was related to mayonnaise treatment (38.92 eggs) which was less than EC (40.16 eggs) and control (97.39 eggs) treatment. The intrinsic rate of increase reduction (rm) of oil treatment showed the effect of oil on pest population dynamic.The intrinsic rate of increase of both formulations and control were 0.065 d-1 and 0.105 d-1, respectively. The finite rate of increase (λ) was also significantly lower for whitefly treated with oil 1.067 d-1 than whitefly in control 1.111 d-1. Furthermore, the net reproductive rate (R0) was 9.49 and 9.53 nymphs/female for mayonnaise and EC formulations which was less than control 26.97 nymphs/female, respectively. The highest generation time (T) was observed in EC oil .formulation with 34.26 d-1 and the lowest was recorded in control treatment with 31.12 d-1, respectively. According to the results of this study, EC and mayonnaise formulations can reduce reproductive capacity of greenhouse whitefly population.