Bark beetle and woodborer insects’ outbreak as a potent driver of Atlas cedar (Cedrus atlantica(Endl.) Carriere) forests dieback in Aures -East Algeria-

Abstract

In order to shed light on the insect part involved in the forest decline associated with Atlas cedar (Cedrus atlantica (Endl.) Carriere.), an etiological study was carried out on eight representative stations in the Aures mountains located in Eastern Algeria. 1,728 woodlogs was prospected, representing three levels of tree's health status (healthy, decaying, and moribund) and four heights (base, medium, crown, and branches) over three years (2010, 2013 and 2016). From this large-scale investigation, it was found that beetles caused the most important damages on Atlas cedar trees, 22 species of which belong mainly to the Scolytidae (Cryphalus numidicus, Scolytus numidicus, Crypturgus cedri, Phloeosinus cedri, and Hylastes batnensis); the Buprestidae (Melanophila marmottani and Anthaxia martini) as well as the xylomycophage Ciidae (Cis corioli) were found to be the most significant decline agents who impacted most of the phytosanitary status of Cedrus atlantica. The thorough examination of the infestation level and the manner of how these insects affected each stage of decline (taking into account the various specimens collected at different high levels) showed an intra and inter-specific heterogeneity, as well as a succession of the xylophagous entomofauna when comparing various stations.

Global Change and Forest Disturbances in the Mediterranean Basin: Breakthroughs, Knowledge Gaps, and Recommendations

“…Insect outbreaks may also have strong impacts on the Mediterranean forest [147][148][149][150]. The interaction with aggravating biotic factors, such as insect attack, determines the tree's resistance to drought.…”

Taxonomic reappraisal of the European fauna of the bark beetle genus Cryphalus (Coleoptera, Curculionidae, Scolytinae)

“…This could suggest the possibility of two generations a year. A study by Beghami et al (2020) showed that C. numidicus from Algeria was active in spring, summer, and autumn and that it could reach three generations per year, with two sister broods in early spring and summer and the second generation in mid-September to early November (under favourable weather conditions). Lieutier et al (2016) stated “The species develops quickly and produces 1–2 generations per year depending on climatic conditions” and “the adults bore very irregular galleries (often invaded by fungi) within the phloem of thin bark on small branches of healthy trees”.…”

“…Brisout de Barneville, 1883; however, only the latter can attack the crown and the mid-trunk of healthy cedars. After P. cedri attacks, C. numidicus further impairs cedar defences through massive attacks ( Beghami et al 2020 ).…”

Review on health status, chemical composition and antimicrobial properties of the four species of the genus Cedrus

“…Insecta -Homoptera -Lachnidae Young twigs and needles Cinara cedri Mimeur (Ülgentürk et al 2020) Insecta -Hemiptera -Aphididae Needles Phaenops (Melanophila) marmottani (Mouna 2009) Beetles Insecta -Coleoptera -Buprestidae Trunk Phloeosinus cedri (Beghami et al 2020) Scolytes Insecta -Coleoptera -Scolytidae Branches and trunk Phloeosinus acatayi Scheldl (Faccoli and Sidoti 2013) Insecta -Coleoptera -Curculionidae Xylems Orthotomicus tridentatus Egg (Avci and Sarikaya 2009) Insecta -Coleoptera -Curculionidae Orthotomicus erosus (Wollaston) (Schvester 1986) Insecta -Coleoptera -Curculionidae Xyloterus lineatus Olivier (Fabre et al 2001;Skrzecz et al 2015) Insecta -Coleoptera -Curculionidae Ergates faber (Gales et al 2018) Cerambycide Insecta -Coleoptera -Cerambycidae Trunk Megastigmus schimitscheki Novitzky (Alptekin et al 1997) Chalcidian Insecta -Hymenoptera-Torymidae Seeds infection is not known. Carpophores produce numerous basidiospores (sexual) in warm weather when the soil is not very dry.…”