Effects of storage at low-temperature of various heteropteran host eggs on the egg parasitoid, Trissolcus semistriatus

Abstract

Various heteropteran host eggs stored under two low-temperatures were tested in the laboratory for their usability in the production of sunn pest egg parasitoid, Trissolcus semistriatus. Parasitism, adult emergence rate and development time were assesed on stored and fresh eggs of Eurygaster integriceps, Dolycoris baccarum, Graphosoma lineatum and Eurydema ornatum. Masses of fresh host eggs in microcentrifuge tubes were maintained at +6°C and )20°C. Every 30 days, 50 eggs of host species were exposed to parasitism by T. semistriatus. The host eggs stored at 6°C remained viable to parasitism by T. semistriatus up to 2 months, while those of stored at )20°C were parasitized at high rates up to 4 months, alhough succesful parasitism rates decrease with time. However, it was indicated that both fresh or stored E. ornatum eggs were not preferred to parasitism by the parasitoid. A longer development time from egg to adult was observed in stored eggs under two tested storage techniques when compared with fresh eggs.

Can native egg parasitoids adopt the invasive brown marmorated stink bug, Halyomorpha halys (Heteroptera: Pentatomidae), in Europe?

“…These assumptions are reinforced by the study of Artem'ev et al (1971), who reported that overall parasitism of E. integriceps by Trissolcus grandis in the field was increased by augmentation of sterilised adult female hosts due to the better development success of the parasitoid in infertile host eggs. The oviposition behaviour of T. cultratus and T. semistriatus was not influenced by freezing the host eggs and confirmed early studies by Kivan and Kilic (2005), who showed that T. semistriatus did not prefer fresh Eurydema ornatum L. (Heteroptera: Pentatomidae) eggs over eggs stored at -20°C. In the same study, it was demonstrated that frozen D. baccarum eggs were more viable for parasitism by T. semistriatus than eggs refrigerated at ?6°C.…”

Quality assessment of Riptortus pedestris (Hemiptera: Alydidae) eggs cold-stored at different temperature and relative humidity regime

“…The suitability of cold-stored host eggs is often evaluated on the basis of parasitism by parasitoids and the successful development of their progeny (Drooz and Weems, 1982;Kivan and Kilic, 2005). However, cold-stored eggs can lose water as they age, and parasitism of such eggs may decrease with time (Kivan and Kilic, 2005;Boivin, 2010), making the use of storage conditions able to preserve the quality of host eggs important.…”

“…However, cold-stored eggs can lose water as they age, and parasitism of such eggs may decrease with time (Kivan and Kilic, 2005;Boivin, 2010), making the use of storage conditions able to preserve the quality of host eggs important.…”

Effects of fenitrothion on Gryon japonicum (Hymenoptera: Platygastridae) parasitizing non-viable, refrigerated eggs of Riptortus pedestris (Hemiptera: Alydidae)

“…To implement a biological control program these parasitoids can be mass reared, and refrigerated host eggs have been used to provide large numbers of hosts in the laboratory colony (Kivan and Kilic, 2005;Mahmoud and Lim, 2007;Alim and Lim, 2009). Furthermore, the release of non-viable, refrigerated eggs in soybean fields as host sources for naturally occurring parasitoids has been suggested as a way to enhance field parasitism by G. japonicum and O. nezarae (Lim and Mahmoud, 2009).…”