author(s)
Somayeh Sanati, Shila Goldasteh, Asghar Shirvani and Maryam Rashki

abstract
Oenopia conglobata contaminata Menetries (Coleoptera: Coccinellidae) is known as one of the most important predators of pests in Iranian gardens and farms. In this research, some of the biological parameters of this Ladybird were investigated by feeding Brevicoryne brassicae at 26 ± 1 °C, (60 ± 1% RH and 16L: 8D). To this end, different growth stages, derived from several breeding generations in the laboratory, were selected, and kept individually, inside Petri, in the growth chamber. In a demographic study, 100 eggs with a life span of less than 24 hours were selected and larvae were fed individually with the host daily. The hatching time of the eggs, and the length of the growth and development of each of the different stages of growth, was visited on a daily basis. Data from Ladybird demography were analyzed using age-stage and bisexual life tables. Mean and error estimates were calculated based on the bootstrap method, with 100,000 replicates. Based on the results obtained, the intrinsic rate of increase in population (r_m) and the rate of increase in population (λ) (per day) were 0.136 ± 0.007 and 1.14± 0.008 Net reproductive rate (R₀), and average generation time (T), were calculated in B. brassicae, respectively, 190.91 eggs and 38.35 days respectively. Considering the demographic parameters, we can say that O. conglobata, by feeding on the host of B. brassicae, is able to complete the cycle of life and reproduction.