Impact of natural enemies on Obolodiplosis robiniae invasion

Abstract

Abstract:The gall midge Obolodiplosis robiniae is a pest of black locust Robinia pseudoacacia. The species was recently introduced into Europe and it is nowadays a usual insect in Slovakia, where two-year field surveys were undertaken during [2007][2008]. The main objective of this study was to determine the natural enemies attacking O. robiniae and estimate their influence on midge population, less than 3 years after its introduction. Eight parasitoids and bushcricket Tettigonia viridissima were responsible for midge regulation. The parasitoid complex was not typically that of an introduced species as it was predicted. Firstly, the midge was heavily influenced by a specialized parasitoid Platygaster robiniae, which was a predominant parasitoid and accounted for 98% of all specimens reared. Secondly, annual larval parasitism varied from 5.4 to 10.8%, though the late season average parasitism achieved 26.0% and often exceeded 40%. P. robiniae was also very efficient in exploiting galls and was capable of consistently regulating midge population. The surveys demonstrated that the average cumulative impact of natural enemies on the midge was substantial. Stably around 20% of attacked galls were recorded during the late summer. Bushcrickets were as efficient as parasitoids and played an important role at control, especially during lack of parasitoids. Greater impact of parasitoids was found in the larger settlements than it was in the countryside, when countertendency was valid for bushcrickets. There is an indication that O. robiniae parasitized by specialized parasitoid, and attacked by bushcrickets represents only a moderate risk for R. pseudoacacia or forest stands.

Studies on the Frequency of Attack Produced by Obolodiplosis robiniae Haldeman in Black Locust Trees from Landscaped Spaces of Cluj-Napoca

“…Often, several females have laid eggs in the same place, and the larvae develop a standard gall where they feed (Molnár et al, 2009). As a result, the average number of larvae in a gala is up to 5-6 larvae (Skuhravá et al, 2007;Tóth et al, 2011), and the maximum number can reach 9-11 larvae (Pernek and Matošević, 2009;Mocreac and Timuş, 2014;Csóka et al, 2017).…”

Future Trends in Obolodiplosis robiniae Distribution across Eurasian Continent under Global Climate Change

“…The assessment and forecasting of the impact of invasive alien species on a global scale have drawn a lot of research interest [ 35 , 36 ]. O. robiniae , a native of the Nearctic region, invaded almost simultaneously from the eastern and western parts of Eurasia at the beginning of the 21st century, and it then spread rapidly, thanks in large part to the belief that it did not pose a serious threat to forest stands, frequent trade activities, and the widespread presence of its host R. pseudoacacia [ 11 , 37 ]. However, our investigation revealed that human negligence was the primary cause for its spread in almost every region inhabited by R. pseudoacacia in China.…”

“…Currently, the natural enemies of O. robiniae include predatory insects such as lacewings, ladybeetles, and crickets [ 37 , 53 ], as well as parasitic insects such as Platygaster robiniae Buhl and Duso, Eupelmus urozonus Dalman, and Mesopolobus mediterraneus Mayr, [ 37 , 54 ], with P. robiniae occupying a dominant position in parasitic wasps. It has been detected in European and East Asian countries, where it is considered to be one of the key contributors lowering the O. robiniae population density [ 55 , 56 , 57 ].…”

“…In order to comprehensively evaluate the changes in the potential suitable regions of O. robiniae in the future periods, specifically years 2041–2060 (2050) and 2061–2080 (2070), we employed three different global climate models (GCMs): BCC-CSM2-MR, CNRM-CM6-1, and IPSL-CM6A-LR [ 37 ]. We used the GCMs from the CMIP6 of the sixth assessment report (AR6) of the Intergovernmental Panel on Climate Change (IPCC).…”

A broad spectrum of host plant responses to the actions of the gall midge: case study of Robinia pseudoacacia L. and Obolodiplosis robiniae (Haldeman)

“…R. pseudoacacia affects numerous ecosystem components leading to the modification of plant and lichen communities, decreasing the richness and diversity of soil invertebrate fauna [19][20][21], to the detriment of birds too [22]. Natural enemies may significantly influence the spread of non-native animals and plants, changing the strength of interactions between these species and the native community -e.g., by decreasing the density and competition of non-native/alien species [23][24][25]. In its native area of North America, more than 70 insect species prey on R. pseudoacacia and some of them were introduced to Europe incidentally [26,27].…”