Rearing Trissolcus japonicus and Trissolcus mitsukurii for Biological Control of Halyomorpha halys

Abstract

Halyomorpha halys is a severe agricultural pest of Asian origin that has invaded many countries throughout the world. Pesticides are currently the favored control methods, but as a consequence of their frequent use, often disrupt Integrated Pest Management. Biological control with egg parasitoids is seen as the most promising control method over the long-term. Knowledge of the reproductive biology under laboratory conditions of the most effective candidates (Trissolcus japonicus and Trissolcus mitsukurii) for optimizing production for field releases is strongly needed. Rearing of these egg parasitoids was tested by offering three different host supply regimes using new emerged females and aged, host-deprived females in different combinations. Results showed a mean progeny per female ranging from 80 to 85 specimens for T. japonicus and from 63 to 83 for T. mitsukurii. Sex ratios were strongly female biased in all combinations and emergence rates exceeded 94% overall. Cumulative curves showed that longer parasitization periods beyond 10–14 days (under the adopted rearing regimes) will not lead to a significantly increase in progeny production. However, ageing females accumulate eggs in their ovaries that can be quickly laid if a sufficient number of host eggs are supplied, thus optimizing host resources. Our data showed that offering H. halys egg masses to host-deprived female Trissolcus once a week for three weeks allowed its eggs to accumulate in the ovary, providing the greatest number of offspring within a three week span.

Reproductive and Developmental Biology of Acroclisoides sinicus, a Hyperparasitoid of Scelionid Parasitoids

“…When provided with carbohydrate in the form of honey, A. sinicus adults live a long time in the lab, similar to T. japonicus or A. bifasciatus [ 34 , 35 ]. Without food A. sinicus can survive for several days, much longer than Trissolcus [ 34 ].…”

“…When provided with carbohydrate in the form of honey, A. sinicus adults live a long time in the lab, similar to T. japonicus or A. bifasciatus [ 34 , 35 ]. Without food A. sinicus can survive for several days, much longer than Trissolcus [ 34 ]. Longevity seems to be host dependant, for A. sinicus females developing on the H. halys – T. mitsukurii combination lived twice as long as those developing on the A. heegeri – Telenomus combination.…”

Modelling the Potential Geographic Distribution of Two Trissolcus Species for the Brown Marmorated Stink Bug, Halyomorpha halys

“…The aims of this paper are to (a) use CLIMEX to assess the potential distribution of T. mitsukurii globally; (b) use CLIMEX to assess the potential range overlap of T. mitsukurii and T. japonicus with H. halys in Australia, in order to understand the climatic potential for these parasitoids to help mitigate the impact of H. halys in Australia; and (c) use the same analyses to consider the situation in Europe, where work is ongoing to assess the potential of both T. mitsukurii and T. japonicus as biological control agents for H. halys [22,[47][48][49][50].…”

Hyperparasitism of Acroclisoides sinicus (Huang and Liao) (Hymenoptera: Pteromalidae) on Two Biological Control Agents of Halyomorpha halys

“…Obligate hyperparasitoids occupy the highest level in multitrophic systems, and they can negatively influence the success of biological control strategies [ 30 , 31 ]. In northern Italy, T. japonicus and T. mitsukurii coexist in many of the areas where they are distributed [ 7 , 32 ]. In the same areas, A. sinicus was often found in both cultivated and semi-natural areas [ 8 , 9 , 25 ].…”