Some like it hot, some not: influence of extreme temperatures on Lariophagus distinguendus and Anisopteromalus calandrae

Abstract

The parasitic wasp species Lariophagus distinguendus (Fö rster) (Hymenoptera: Pteromalidae) and Anisopteromalus calandrae (Howard) (Pteromalidae) are used for inoculation biological control of the granary weevil Sitophilus granarius (L.) (Coleoptera: Curculionidae) in grain stores in Europe. To assess their suitability for biological control under extreme temperatures in winter and summer, we studied the influence of temperatures on their parasitization behaviour under natural fluctuating temperature conditions in the field and under constant temperature conditions in the laboratory. At low temperatures (£20°C), L. distinguendus showed a higher parasitization rate than A. calandrae. At high temperatures ( ‡25°C), A. calandrae performed better than L. distinguendus that was negatively affected already at temperatures above 30°C. These findings suggest a temperature-dependent release of either L. distinguendus or A. calandrae to allow a more efficient application of the wasps in biological control.

Differential susceptibility and suitability of domestic and wild apple species for a florivorous weevil and its parasitoids

“…), potential differences in temperature between sites might influence infestation and parasitization (Niedermayer et al. ).…”

“…Temperature was measured every hour at each site with thermobuttons (Maxim Integrated Products, Inc.: Thermochron â iButton â DS1921G) from beginning of March until end of April during main weevil activity (Gratwick 1992;Duan et al 1996). As weevil activity is reduced at temperatures below 5°C (Duan et al 1996;Toepfer et al 1999a), potential differences in temperature between sites might influence infestation and parasitization (Niedermayer et al 2013).…”

Lariophagus distinguendus (Hymenoptera: Pteromalidae) (Förster)—Past, Present, and Future: The History of a Biological Control Method Using L. distinguendus against Different Storage Pests

“…Since reproduction values of the wasps at low temperatures are higher than those of the weevils, L. distinguendus should be able to control granary pest populations even at low temperatures. In this context, Niedermayer et al examined the parasitization ability of L. distinguendus compared to that of the closely related parasitoid A. calandrae under extreme temperature conditions [72]. L. distinguendus performs better at lower temperatures whereas A. calandrae performs better at warmer temperatures.…”

“…L. distinguendus should be released during the cold season or in colder geographic regions. During summer or in warmer areas A. calandrae is a suitable alternative [70,71,72]. …”

Heat shock sensitivity of adult male fertility in the parasitoid wasp Anisopteromalus calandrae (Hymenoptera, Pteromalidae)

“…Most studies on temperature-dependent performance have focused on the "zone of effective temperature" (Girish, 1965), namely the temperature range in which insects are active. Very few studies exist on the influence of extreme temperatures which occur under natural conditions, for example, the minimum and maximum effective temperature in winter and summer (but see Niedermayer et al, 2013). Insects are especially vulnerable to such extremes because of their small size and ectothermic physiology, and temperature plays a vital role in survival and reproductive success (Lee et al, 1996;Rinehart et al, 2000).…”