Hyposoter didymator

Hyposoter didymator (Thunberg)

Systematic position: Insecta, Holometabola, Hymenoptera, Apocryta, Chalcidoidea, Ichneumonidae.

Morphology: The body and the head, including the straight antennae of the adult, are mostly black, the legs are yellow

Geographical distribution: Mediterranean region, Russia and Australia.

Life history: Hyposoter didymator is a solitary endoparasitoid that attacks the young larvae of some noctuids. It develops in the host for about 2 weeks, emerges from the dead larva and spins a silken cocoon wherein it pupates within 1–2 days. Females live for about 4-5 weeks after emergence, males only 2-3 weeks.

Economic importance: Hyposoter didymator is a major enemy of certain economically important pests, such as Helicoverpa armigera and Spodoptera exigua in the field and in greenhouses. Parasitism on the former pest was much higher when it infested sorghum, sunflower, cotton and soybean than when on chickpeas (Cicer arietinum L.). Parasitized larvae eat less, lose weight and cease developing at their 4th stage. Hyposoter didymator also transmits a viral disease to its hosts. Mass-rearing methods of H. didymator are available.

Effect of pesticides: Many commonly used insecticides (like imidacloprid and pyrethrins had little effect on the parasite while developing inside the host cocoon, but fipronil was very toxic.

References

Hatem, A. E., Shawer, D. M., and Vargas-Osuna, E. 2016. Parasitism and optimization of Hyposoter didymator (Hymenoptera: Ichneumonidae) rearing on Spodoptera Littoralis and Helicoverpa armigera (Lepidoptera: Noctuidae). Journal of Economic Entomology 109: 1058–1063.

Medina, P., Morales, J.J., Budia, F., Adan, A., Del Estal, P. and Viñuela, E. 2007. Compatibility of endoparasitoid Hyposoter didymator (Hymenoptera: Ichneumonidae) protected stages with five selected insecticides. Journal of Economic Entomology 100: 1789-96.

Mironidis, G. and Savopoulou-Soultani, M. 2009. Development, survival and growth rate of the Hyposoter didymator-Helicoverpa armigera parasitoid-host system: Effect of host instar at parasitism. Biological Control 49: 58-67.

Murray, D.A.H., Rynne, K.P., Winterton, S.L., Bean, J.A. and Lloyd, R.J. 1995. Effect of host plant on parasitism of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) by Hyposoter didymator Thunberg (Hymenoptera: Ichneumonidae) and Cotesia kazak (Telenga) (Hymenoptera: Braconidae). Austral Entomology 34: 71-73.

Schneider, M.I., Smagghe, G., Pineda, S. and Viñuela, E. 2004. Action of insect growth regulator insecticides and spinosad on life parameters and absorption in third instar larvae of the endoparasitoid Hyposoter didymator. Biological Control 31: 189-198.

Schneider, M.I. and Viñuela, E. 2007. Improvements in rearing method for Hyposoter didymator (Hymenoptera: Ichneumonidae), considering sex allocation and sex determination theories used for Hymenoptera. Biological Control 43: 271-277.

Sertkaya, E., Ahmet Bayram, A. and Kornosor, S. 2004. Egg and larval parasitoids of the beet armyworm Spodoptera exigua on maize in Turkey Phytoparasitica 32: 305-312.

Website https://www.google.co.il/search?q=hyposoter+didymator&tbm=isch&tbo=u&source=univ&sa=X&ved=0ahUKEwjLzLbos-XWAhVFVhoKHeWqBugQsAQIQg&biw=1097&bih=552