Prey consumption preferences of Serangium parcesetosum Sicard (Col., Coccinellidae) for different prey stages, species and parasitized prey
Al-Zyoud, F. and C. Sengonca
Journal of Pest Science 77: 197-204, 2004
Abstract: Serangium parcesetosum Sicard (Col., Coccinellidae) is considered one of the important predators of whiteflies. However, knowledge about preference by prey consumption of S. parcesetosum on different prey stages, species and parasitized prey was still lacking in the literature. Therefore, the purpose of the present work was to investigate the preference by prey consumption of S. parcesetosum on different stages of B. tabaci, different prey species and parasitized B. tabaci by Encarsia formosa Gahan (Hym., Aphelinidae) at different temperatures in the laboratory. The results on prey stage preference by S. parcesetosum with eggs, nymphs and puparia of Bemisia tabaci (Genn.) (Hom., Aleyrodidae) showed that L2 and L4 predatory instars preferred more puparia than nymphs and eggs. The mean daily prey consumption was 5.1-9.0, 4.5-6.2 and 3.6-4.3 by L2 as well as 6.4-9.7, 5.5-8.5 and 2.5-7.5 by L4 puparia, nymphs and eggs, respectively. In contrast, adult females indicated significantly more preference for puparia and nymphs, where they consumed a mean daily of 6.4-7.5 puparia and 5.1-6.7 nymphs, while from eggs it valued 3.0-4.7. Prey species preference by S. parcesetosum showed that at 18°C and 30°C, all S. parcesetosum stages tested were preferred significantly B. tabaci and Trialeurodes vaporariorum Westwood (Hom., Aleyrodidae) rather than the other three prey species offered. At both temperatures, all predatory stages preferred more B. tabaci than T. vaporariorum, except L2 instar at 18°C, which had significantly more preference for B. tabaci than T. vaporariorum. In contrast, very few individuals were significantly consumed from Aphis gossypii Glover (Hom., Aphididae), Frankliniella occidentalis (Pergande) (Thys., Thripidae) and Tetranychus urticae Koch (Acari, Tetranychidae). At 18°C, a mean daily of 7.5-8.0, 6.6-9.0 and 6.7-8.1 B. tabaci as well as 5.3-6.4, 5.4-7.8 and 5.6-6.3 T. vaporariorum was consumed by L2, L4 and adult females, respectively, while at 30°C, L2, L4 and adult females consumed a mean of 9.3, 8.8-9.7 and 8.3-9.7 B. tabaci/day as well as 8.3-9.0, 7.8-9.1 and 5.5-8.4 T. vaporariorum/day, respectively. S. parcesetosum L2 and L4 instars as well as adult females and males at both studied temperatures were significantly tended to avoid five days B. tabaci puparia after parasitism by E. formosa and fed on more unparasitized whiteflies. At 18°C, the mean daily consumption was 8.7 and 0.2 (L2), 11.1 and 0.6 (L4), 12.1 and 1.0 (♀♀) as well as 10.5 and 0.2 (♂♂), while at 30°C it valued 15.9 and 0.5 (L2), 19.8 and 1.0 (L4), 18.9 and 1.2 (♀♀) as well as 17.4 and 0.6 (♂♂) from unparasitized and parasitized B. tabaci puparia, respectively.
Keywords: Prey consumption, preference, Serangium parcesetosum, prey, parasitized prey, biological control
