Life-history parameters of Encarsia formosa, Eretmocerus eremicus and E. mundus, aphelinid parasitoids of Bemisia argentifolii (Hemiptera: Aleyrodidae)

Abstract

Abstract. Life-history parameters (juvenile development time, adult longevity, host instar preference and rate of parasitism) of four parasitoids of Bemisia argentifolii (two strains of Encarsia formosa (D and B), Eretmocerus eremicus and Eretmocerus mundus) were studied in the laboratory. At 15°C juvenile development time was the shortest for E. formosa B (48 days), longest for E. eremicus (79.3 days) and intermediate for E. formosa D (62.8 days) and E. mundus (64 days) at 15°C. With increase in temperature, development time decreased to around 14 days for all species/strains at 32°C. The lower developmental threshold for development was 11.5, 8.1, 13.0 and 11.5°C for E. formosa D, E. formosa B, E. eremicus and E. mundus, respectively. E. formosa D and B, and E. mundus all appeared to prefer to parasitize 3 rd instar nymphs. The presence of hosts shortened adult longevity in most of the parasitoids, with the exception of E. formosa B, which lived longer than other species/strains irrespective of the presence of hosts. At 15°C daily parasitism was very low by all parasitoids. The two Encarsia strains had a constant, but low rate of reproduction during adult life, while the two Eretmocerus species had a very high rate of reproduction when one-day old, which then decreased very quickly. Lifetime fecundity, estimated using a non-linear model, indicated that it was higher for the two Encarsia strains than for the Eretmocerus species. Life history parameters reported in the literature for the four parasitoids are reviewed and compared with our results. Finally, the potential value for the biological control of whiteflies on greenhouse crops of parasitoids having either a high reproductive rate over a short period (Eretmocerus spp.) or a low rate of reproduction over a long period (Encarsia spp.) is discussed.

Effect of temperature on the life history of Encarsia bimaculata (Hymenoptera: Aphelinidae), a parasitoid of Bemisia tabaci (Hemiptera: Aleyrodidae)

“…Over a similar temperature range (22°C to 30°C), the developmental time of E. bimaculata (Bundaberg population) (De Barro et al, 2000) ranged from 16-18 d when reared on host feeding on hibiscus. Antony et al (2004) report that the developmental periods for male and female E. bimaculata * Within the column of rm, the values with different letters are significantly different at P < 0.05 (F = 1944.42, df = 4,15, P < 0.0001 and 12.9 d for development at 20°C, 25°C and 30°C, respectively, while Qiu et al (2004b) report that the development period of E. formosa at 32°C is about 14 d. While temperature clearly influences the rate of development, the above differences are also likely to be affected by differences in the genetic stock from which the parasitoids were obtained and the host plant of the whitefly host.…”

Quantification and ultrastructure of oosorption inEretmocerus eremicus (Hymenoptera: Aphelinidae)

“…In addition, an unknown species of Eretmocerus has recently been designated as "strictly" pro-ovigenic (OI ϭ 1.0; Jervis et al, 2001). Finally, age-specific fecundity analyses suggest that nearly all oviposition in E. eremicus and E. mundus on B. tabaci occurs within 2 days of eclosion (Qiu et al, 2004), a finding consistent with the possession of a high OI.…”

Parasitism, host feeding and immature development of Encarsia formosa reared from Trialeurodes vaporariorum and Bemisia tabaci on Trialeurodes ricini

“…Encarsia formosa can feed, oviposit and complete development in all nymphal instars of T. vaporariorum and B. tabaci (Qiu et al 2004;Zang and Liu 2008;Grille et al 2012).…”