INTERACTIONS BETWEEN Psyllobora vigintiduopunctata (L.) (COLEOPTERA: COCCINELLIDAE) AND CUCURBIT POWDERY MILDEW

In cucurbit production, fungicides used to control powdery mildew, which significantly reduces product yield and quality, generate environmental pollution and residues. Sustainable approaches are therefore needed to control this disease. To evaluate the potential of Psyllobora vigintiduopunctata (Linnaeus) (Coleoptera: Coccinellidae) as a biological control agent against Erysiphe cichoracearum (DC.) (Erysiphales: Erysiphaceae), biological parameters and population dynamics were determined under controlled conditions (25±2 °C, 70±5% humidity, 12:12 photoperiod) for two generations. A two-sex, age-stage life table approach was used to analyse the data. The results indicated that mean lifetime fecundity ranged from 317.48±142 to 376.55±146 eggs per female. P. vigintiduopunctata completed its development in 26.7–28.4 days in both generations. The total longevity of females was 102 to 108 days, while males had a lifespan of 106 to 107 days. The intrinsic rate of increase (r) of the predator on E. cichoracearum was found to be between 0.0788 and 0.0829 females/day, while the mean generation time (T) varied between 58.7 and 61.5 days. The gross reproductive rate (GRR), which represents the number of offspring produced per female per generation, ranged from 219.5 to 228.5 individuals. These laboratory results indicate a promising potential for P. vigintiduopunctata as a biological control agent against E. cichoracearum in cucurbits.