Environmental risk assessment for Neodryinus typhlocybae, biological control agent against Metcalfa pruinosa, for Austria

Abstract

The potential environmental risks of Neodryinus typhlocybae, a parasitic wasp from North America, were evaluated with regard to its safe use as an exotic biocontrol agent for the planthopper Metcalfa pruinosa in Austria. Following an earlier host range study of N. typhlocybae conducted in the laboratory, the present study assessed the potential for establishment and spread as well as negative indirect effects on non-target organisms. The potential release sites in Austria were analysed for matching of the climatic requirements for establishment of N. typhlocybae. The two proposed release locations, Vienna and Graz, have a predominantly similar climate to the parasitoid's region of origin, though the comparably cooler mean summer temperatures might result in a low emergence rate of the partial second generation. The natural spread potential of N. typhlocybae was reviewed and is considered to be sufficiently good for released individuals to reach nearby sites infested with M. pruinosa. However, a perceptible spreading of N. typhlocybae females only occurs a few years after release and seems to be strongly dependent on the host density. Gelis areator, a hyperparasitoid of N. typhlocybae known to occur in Austria, might have negative effects on the population of the beneficial organism. Advantages and disadvantages of chemical and biological control methods against M. pruinosa were evaluated. It is concluded that N. typhlocybae is very well suited as a biological control agent for M. pruinosa in Austria, as no adverse effects on non-target species are expected but its release offers advantages with regard to sustainable and environmentally friendly pest management.

First record of Neodryinus typhlocybae in Hungary (Hymenoptera: Dryinidae)

“…Remarks -Neodryinus typhlocybae, originally a Nearctic species, has been introduced to several southern and Central European countries (Strauss 2012). However, it has not been intentionally introduced to Hungary, therefore its occurrence in Hungary remains unclear.…”

Journal of Plant Protection Research

“…The first specimens of N. typhlocybae originating from the USA (area of Connecticut) were repeatedly released in northwestern Italy in 1987 and the following years (Girolami and Camporese 1994). Apart from many parts of Italy, N. typhlocybae was also introduced into Croatia, France, Greece, the Netherlands, Slovenia, Spain and Switzerland (Strauss 2009(Strauss , 2012. The appearance of the species in Austria, Hungary, Bulgaria and Slovakia during the last decade is associated with its natural dispersal across central Europe (Vétek et al 2019).…”

Occurrence Prediction of the Citrus Flatid Planthopper (Metcalfa pruinosa (Say, 1830)) in South Korea Using a Random Forest Model

“…Guillemaud, et al [57] reported two main factors promoting biological invasion: Human activities and the biological adaptation of species. Human activities, including international trade and movement of vehicles among local regions, are highly responsible for recent biological invasions by moving invasive species and causing long distance dispersal [4,5,9,14,25,27,[58][59][60][61][62]. Human activities also promote the dispersal of invasive species by modifying and disturbing natural habitats and providing the possibility of the introduction of new species into ecosystems [63].…”