Survey of Natural Enemies of the Invasive Boxwood Moth Cydalima perspectalis in Southwestern Mediterranean Europe and Biocontrol Potential of a Native Beauveria bassiana (Bals.-Criv.) Vuill. Strain

Abstract

Cydalima perspectalis (Lepidoptera: Crambidae), a species native to East Asia, has been especially devastating in the Mediterranean region and Catalonia, northeast Spain, where Buxus sempervirens is an essential component of the natural forest. As an invasive species, the lack of biotic mortality factors in the arrival region has been one of the main factors allowing its expansion. Therefore, this study aimed to collect and identify possible indigenous natural enemies adapting to the new species in the boxwood of the southwest Mediterranean region. Later, the efficacy of some of the collected species for controlling C. perspectalis larvae was tested in laboratory conditions. The larval collection was carried out in successive years in the boxwood of the region. Several collected larvae were infected with an entomopathogen, Beauveria bassiana, or parasitized by Compsilura concinnata, both common in native Lepidoptera caterpillars. The B. bassiana strain was found to be highly virulent against the developed larvae of C. perspectalis, which suggests that B. bassiana may be an effective treatment in parks and gardens when the first overwintering larvae are detected. The biology of the parasitoid identified is not very well known in Europe, which suggests the necessity of studying its biology and alternative hosts in the region in order to improve its population.

First Record of <em>Nemorilla floralis</em> (Fallén 1810) (Diptera, Tachinidae) Parasitism on Box Tree Moth – <em>Cydalima perspectalis</em> (Walker 1859) (Lepidoptera, Crambidae) Larvae

“…-Criv.) Vuill., 1912 (Ascomycota: Hypocreales), another potential control agent [13]. In this research, we confirm that at least 1.2 -2.4 % parasitism rate was achieved by N. floralis, depending on whether one or two hosts had been parasitized and whether other tachinids in the collection had died in transit along with their hosts.…”

“…Studies in natural boxwood forests in France have reported 1.83% parasitization by the tachinid fly C. concinnata [12]. Compsilura concinnata was the only parasitoid to emerge from 800 5 th and 6 th instar larvae collected over 5 years in Catalonia, Spain; parasitism rates at six locations ranged from 0 to 20% [13]. In that study, 0.5% of 42 larvae that died before pupation were found to be infected by a strain of the fungus Beauveria bassiana (Bals.…”

“…communis (Ness 1834) (Hymenoptera, Pteromalidae), a parasitoid wasp in Britain [5], and Apechthis compunctator (L.) (Hymenoptera, Ichneumonidae), a pupal parasitoid reported from Switzerland [4]. Studies in natural boxwood forests in France and Spain report parasitization by the tachinid fly C. concinnata [12,13].…”

Identification and biocontrol potential evaluation of a naturally occurring Metarhizium pingshaense isolate infecting tea weevil Myllocerinus aurolineatus Voss (Coleoptera: Curculionidae)

“…The translation elongation factor 1α gene (EF-1α) and β-tubulin gene (TUB) were amplified by PCR. Specifically, the 5′ terminal sequence of EF-1α (approximately 1200 bp) was amplified using primers EF1T and 1567R, whereas the 3′ terminal sequence was amplified using primers tef1fw and 1750-R (López et al 2022;Senthil et al 2023). The Pbeta-F and Pbeta-R primers were used to amplify the TUB gene (Wei et al 2023).…”