Journal of Plant Diseases and Protection 111: 598-609, 2004

Life table of the entomophagous ladybird Serangium parcesetosum Sicard (Col., Coccinellidae) by feeding on Bemisia tabaci (Genn.) (Hom., Aleyrodidae) as prey at two different temperatures and plant species

Abstract: Serangium parcesetosum Sicard (Col., Coccinellidae) seems to be a specialist predator of whiteflies. However, the knowledge about its life table parameters with the cotton whitefly, Bemisia tabaci (Genn.) (Hom., Aleyrodidae) as prey was insufficient on the influence of temperature, prey species and plant species on its biology in the literature. Therefore, in the present work, development, mortality, sex ratio, longevity and reproduction of S. parcesetosum were studied in the laboratory at 18 ± 1 °C and 30 ± 1 °C on cotton and cucumber leaves. S. parcesetosum was able to develop and reach adult stage at both temperatures and plant species tested. Temperature, prey’s host plant species and sex of the predator had influenced the mean developmental duration of all stages of the predator. Total developmental duration at 18 °C was a mean of 43.4 (♀♀) and 42.4 (♂♂) days as well as 45.2 (♀♀) and 43.4 (♂♂) days, while at 30 °C it valued a mean of 17.2 (♀♀) and 16.2 (♂♂) days as well as 15.9 (♀♀) and 15.1 (♂♂) days on cotton and cucumber, respectively. Total mortality percentage of S. parcesetosum during development from egg to adult was also affected by temperature and plant species, where it was higher at 18 °C than 30 °C on both plant species, and it was higher on cotton than cucumber at both temperatures. The sex ratio (♂♂: ♀♀) of S. parcesetosum was 1:0.9 and 1:0.8 at 18 °C, while at 30 °C it valued 1:1.1 on cotton and cucumber, respectively. Longevity of S. parcesetosum varied significantly according to temperature, prey’s host plant species and sex of the adults, and it was significantly longer at 18 °C than 30 °C for both sexes on both plant species and it was for females significantly longer than males. Temperature and plant species had significantly influenced pre-oviposition, oviposition and post-oviposition periods of S. parcesetosum. At 18 °C, adult females began oviposition 13 and 17 days after emergence with a mean total fecundity of 52.4 and 24.7 eggs/♀, while at 30 °C they began oviposition after 6 and 7 days, where the mean total fecundity was 31.0 and 97.7 eggs/♀ on cotton and cucumber, respectively.