Budburst phenology and host use by Operophtera brumata (Linnaeus, 1758) (Lepidoptera: Geometridae) in three Mediterranean oak species

Abstract

& Key message Operophtera brumata L. performance varies among three Mediterranean oak species. Quercus canariensis Willd is more susceptible to infestation probably due to its (i) early leafing, (ii) high nutritional value for the larvae, and (iii) widespread abundance. & Context Larvae of Operophtera brumata were observed for the first time in an outbreak in Tunisia affecting Quercus canariensis, Quercus afares Pomel, and Quercus suber L. Due to its polyphagous nature and the important ecological and economic damage it causes, it is most relevant to understand its interaction with North African oaks species. & Aims In this paper, budburst phenology of the three oak species, larval performance, and genetic patterns of O. brumata were studied in northwestern Tunisia. & Methods In the spring of 2010, 2011, and 2012, budburst phenology of host species and larval densities were monitored weekly. Larval performance of O. brumata on the three oak species was analyzed. DNA extraction, PCR, and DNA sequencing were performed. & Results Budburst of Q. canariensis and Q. afares was earlier than Q. suber. Q. canariensis was the most infested host. Larvae which fed on Q. canariensis had faster development, lower mortality, and higher pupal weight than larvae fed on Q. afares and Q. suber. Molecular analyses showed that Tunisian haplotypes were not different from those in Spain, Italy, and Germany. & Conclusion Results indicated differences in larval performance. Q. canariensis was the most favorable host species. Its high density in the field and early leafing coinciding with larval hatching made this species particularly susceptible.

Identification of winter moth (Operophtera brumata) refugia in North Africa and the Italian Peninsula during the last glacial maximum

“…Again, we can only speculate as to the role of the Mediterranean Sea as a barrier without sampling across northern Africa, southern Spain, and from Mediterranean islands (such as Sicily and Sardinia). However, when our results (i.e., locally distinct populations based on nuclear loci) are combined with mitochondrial studies that have uncovered limited genetic diversity among winter moth populations (Gwiazdowski et al, ; Mannai et al, ), it suggests that winter moth may be a relatively new addition to the European ecological community, and either became established in Europe prior to the onset of the last glacial cycle, or speciated in Europe shortly before this event.…”

“…In Tunisia, winter moth has mainly been observed on Q. canariensis in both mixed oak (Aïn Zena, 36.435°N, 8.515°E) and pure Q. canariensis oak (Mzara Forest, 36.769°N, 8.72°E) forests, with lower densities being found on Q. afares and Q. suber compared with Q. canariensis in Aïn Zena. These differences may be the result of differences in budburst timing of different oak species (Mannai, Ezzine, Hausmann, Nouira, & Ben Jamâa, ).…”

“…Therefore, we were curious as to whether or not the recent reports of outbreaks in northwestern Tunisian oak forests were the result of a recent introduction (as has been the case in North America), or whether a native population has achieved outbreak levels for some other reason. Previously, Mannai et al () explored the native/nonnative status of outbreaking Tunisian winter moth populations by sequencing a fragment of the mitochondrial (mtDNA) locus cytochrome oxidase I (COI) from field‐collected larvae in Tunisian oak forests, and compared these sequences to those published in NCBI GenBank and the Barcode of Life Data Systems (BOLD) database. This work confirmed the field identifications of winter moth in northwestern Tunisia.…”

Trophic generalism in the winter moth: a model system for phenological mismatch

“…However, trophic generalism in the winter moth is largely only mentioned in passing in the phenological literature (Table S1). Instead, the focus has mainly been on a single host-plant, English oak Quercus robur L. (Table S2; Buse et al, 1998Buse et al, , 1999Tikkanen and Julkunen-Tiitto, 2003;Van Dongen, 2006;Mannai et al, 2017;Kulfan et al, 2018). The reasons for this emphasis seem to be largely historical, tracing back to the earliest considerations of phenological synchrony in the winter moth (e.g.…”

Northern Fennoscandia via the British Isles: evidence for a novel post-glacial recolonization route by winter moth (Operophtera brumata)

“…In northern Fennoscandia, winter moth has expanded its distribution northward, presumably in response to warming climates, and has in recent decades reached outbreak status as far north as the low arctic timberline in northeastern Norway (Jepsen et al 2008(Jepsen et al , 2011. Winter moth is native to Europe, northern Africa, and eastern Asia, and occasionally reaches outbreak densities across much of its distribution (Ferguson 1978, Tenow et al 2013, Young et al 2014, Jepsen et al 2016, Mannai et al 2017. However, persistent cyclic population dynamics, with periods of 7-15 years, are mainly found in northern Fennoscandia and high elevation regions in south-central Norway (Vindstad et al 2019).…”