The Seasonal Population Dynamics of Corythucha arcuata (Say, 1832) (Hemiptera: Tingidae) and the Relationship between Meteorological Factors and the Diurnal Flight Intensity of the Adults in Romanian Oak Forests

Abstract

To control a forest pest, it is necessary to understand the biotic and/or abiotic factors that can lead to population regulation. Such knowledge is even more critical if the pest is an invasive alien species. This is the case for Corythucha arcuata (Say, 1832), commonly known as the oak lace bug (OLB), an alien insect species that has invaded oak forests on a large scale, both in Romania and other European countries. In this study, we set out to examine the relationship between adults of this species and meteorological factors, such as air temperature and humidity. The study lasted for two years (2019–2020) and was performed on three plots in Romania, in Ilfov, Giurgiu, and Călărași counties. In the first year, the seasonal dynamics of the OLB populations and the meteorological factors potentially influencing those were studied, whilst in the second year, the dynamics of the diurnal activity of the insect population were examined. We found that Corythucha arcuata experienced two population peaks—in July and August—and a diurnal population dynamic that reached a maximum at midday. Data analysis indicated that, for most of the time, the adult activity was influenced by both temperature and humidity. In addition, the population dynamics were not constant over the course of the day, preferring relatively high temperatures and low humidity but not exceeding certain thresholds of thermal discomfort.

Study on the Ecology, Biology and Ethology of the Invasive Species Corythucha arcuata Say, 1832 (Heteroptera: Tingidae), a Danger to Quercus sp. in the Climatic Conditions of the City of Sibiu, Romania

“…In the current context of the invasion in Sibiu, the most important step was to detect and to monitor the species, to understand the behavior of this pest, to contribute to form decisions based on scientific research on how best to control and limit the attack in the forest ecosystems in Sibiu County. During the two-year study in Sibiu, information on population abundance and environmental conditions in the area was documented, as well as the identification of factors influencing the development and reproduction of the invasive OLB populations [70]. Following our study, we conclude that the likely origin of the OLB infestation in Sibiu could be Cluj County, located 175 km from where the species was reported in 2017 in Baciu Forest [66].…”

“…Early detection of infected host trees and applying control precautions reduced the chance of spreading to new areas. The published information until now about the spread of OLB in Romania [70] and other European countries can be helpful in predicting its likely future spread. In Sibiu, OLB was found mainly on oak species (Quercus spp.…”

“…From 2016, was reported in other European countries: Albania, Bosnia and Herzegovina, Greece and Ukraine [48,[50][51][52][53][54]. [19,20]; 2002-Switzerland [21,22]; 2003-Turkey [9,23,24,[25][26][27][28]; 2005-Iran [28]; 2009-Poland [29]; 2012-Bulgaria [30,31]; 2013-Hungary [32,[34][35][36][37]; 2013-Croația [39]; 2013-Serbia [40][41][42]; 2015-Russia [24,[43][44][45][46][47]; 2015-Romania [52,62,64,65,[67][68][69][70]; 2016-Albania, Bosnia and Herzegovina, Greece and Ukraine [48,50,51,[53][54]; 2017...…”

“…During 2016, OLB was found in other west locations, in Timișoara city and Denta [63], in Dolj county (in Craiova and Balasan) and in Ciolănești, Teleorman county [66]. From the studies carried out between 2016-2022, by the National Institute for Research and Development in Forestry 'Marin Dracea' specialists [62,64,65,[67][68][69][70], OLB was reported in 67 of the 124 locations studied, mainly in West, Central and South part of Romania (Figure 2). In recent years, it has been reported in more areas of Romania where the host species are: Quercus robur, Q. petraea, Q.cerris, Q. frainetto and Q. pubescens but also on Ulmus minor, Tilia platyphyllos, Tilia tomentosa and Prunus cerasifera [66].…”

Infestation intensity by the invasive oak lace bug, Corythucha arcuata (Say) in mixed and pure oak stands

“…After hibernation, adults move to fresh oak leaves where eggs are deposited after some time of maturation feeding. Two to three generations can develop in a season leading to accumulating damage and visible symptoms to the leaves (Bălăcenoiu, Simon, et al., 2021; Paulin et al., 2020). Because most radial growth of oaks occurs in the first half of the growing season, feeding by C. arcuata does not appear to have a dramatic effect on annual wood increment; however, a cumulative effect from repeated damage seems likely (Paulin et al., 2020).…”