Leptographium sinoprocerum sp. nov., an undescribed species associated with Pinus tabuliformis-Dendroctonus valens in northern China

Abstract

During a study of ophiostomatoid fungi associated with the invasive pest Dendroctonus valens in the Pinus tabuliformis ecosystem in northern China, a multigenic (ITS2-LSU, beta-tubulin and EF1-alpha) phylogenetic analysis and examination of morphological features revealed in addition to Leptographium procerum the occurrence of an undescribed species. The new species, Leptographium sinoprocerum, belongs to the L. procerum-L. profanum clade. Both L. procerum and L. sinoprocerum are similar to each other and occur sympatrically in the ecosystem studied. Nevertheless L. sinoprocerum can be distinguished from L. procerum by shorter conidiophore stipes arising from both submerged and aerial hyphae, slightly more oblong conidia, a granular ornamentation on the submerged hyphae and dark olivaceous colonies on MEA.

Grosmannia and Leptographium spp. associated with conifer-infesting bark beetles in Finland and Russia, including Leptographium taigense sp. nov.

“…The L. procerum-complex presently comprises nine species (listed in the Results section), all known only by their morphologically similar anamorphs, with relatively long conidiophores. Eight of the species have been described since 2000 Masuya et al 2000;Zhou et al 2008;Lu et al 2008;Paciura et al 2010). Six of these species were described from pine and/or pine-infesting beetles in Japan (Masuya et al 2000), Bhutan (Zhou et al 2006) and China (Lu et al 2008;Paciura et al 2010).…”

“…procerum has been associated with a root decline disease known as white pine root decline particularly in the North Central and Eastern United States (Kendrick 1962;Alexander et al 1988) although its role in tree death has been deeply disputed Wingfield et al 1988). Recent outbreaks of D. valens in China, have again raised the question as to the role of L. procerum, the most dominant species found with the insect, in tree death (Lu et al 2008(Lu et al , 2009a. While inoculation trials have shown that it is not a virulent pathogen, its association with a novel host and in a new environment appears to influence beetle behavior and its potential to contribute to tree death (Lu et al 2009b(Lu et al , 2011.…”

Ophiostomatoid fungi (Ascomycota) associated with Pinus tabuliformis infested by Dendroctonus valens (Coleoptera) in northern China and an assessment of their pathogenicity on mature trees

“…The Chinese strains of the different species closely reflected the species descriptions (Kendrick 1962;Wingfield and Marasas 1983;Wingfield 1985;Hutchison and Reid 1988;Harrington et al 2001;Jacobs et al 2005;Kim et al b, c;Lu et al 2008). The identification of the Chinese strains of L. koreanum was confirmed by successful mating with tester strains of this species (Masuya et al 2005), resulting in the production of fertile perithecia.…”

“…The most ophiostomatoid fungi observed in association with P. tabuliformis/RTB in northern China, with the possible exception of L. procerum (Lu et al 2008), could be considered as native. Thus, it appears that the introduced RTB is able to form new associations with native fungi, as already demonstrated for other introduced beetles Hausner et al 2005).…”

“…Zhou et al (2000) and L. sinoprocerum Q. Lu et al (2008), were originally described based on Chinese isolates.…”