Ophiostomatoid fungi associated with Ips cembrae in Japan and their pathogenicity to Japanese larch

Abstract

Six ophiostomatoid fungi, i.e., Ceratocystiopsis minuta, Ceratocystis laricicola, Ophiostoma brunneo-ciliatum, O. laricis, O. piceae and Ophiostoma sp., were isolated from the galleries of Ips cembrae on Japanese larch (Larix kaempfer/) logs in central Honshu, Japan. Japanese larch trees approximately 30 yr old were inoculated with all six fungi. Ceratocystis laricicola produced the largest lesions on the inner bark around the inoculation point and the largest dry zone in the sapwood. Furthermore, C. laricicola was the only fungus associated with I. cembrae that had the ability to kill Japanese larch, death occurring in 30-yr-old trees within 3.5 mo after inoculation.

Phylogenetic relationships between the European and Asian eight spined larch bark beetle populations (Coleoptera, Scolytidae) inferred from DNA sequences and fungal associates

“…The fungi isolated in this study are similar to those previously recorded from Japanese beetles (Westhuizen et al, 1995;Yamaoka et al, 1998). There are, however, differences between the fungal assemblages associated with the two beetle populations.…”

“…There are, however, differences between the fungal assemblages associated with the two beetle populations. C. minuta, C. laricicola, O. brunneo-ciliatum, O. piceae and presmably also Ophiostoma sp., a hitherto unde scribed species, that resembles O. europhioides (Wright & Cain) Solheim, are associated with both European and Japanese I. cembrae (Westhuizen et al, 1995;Yamaoka et al, 1998). O. bicolor was rarely associated with Euro pean and never with Japanese beetles.…”

“…Likewise, Ceratocystiopsis sp. and the Graphium sp., two important ele ments of the mycobiota of I. cembrae in Europe, are not associated with this insect in Japan (Yamaoka et al, 1998). Ophiostoma laricis, described by Westhuizen et al (1995), was commonly associated with I. cembrae in Japan (Yamaoka et al, 1998), but not in Europe.…”

“…), host trees and collectors of the larch bark beetles used in this study -see also Fig. 1 laricicola, are associated with I. cembrae (Westhuizen et al, 1995;Yamaoka et al, 1998). There are no studies on the fungi associated with I. cembrae in continental Europe, where the insect is native.…”

The Ophiostoma clavatum species complex: a newly defined group in the Ophiostomatales including three novel taxa

“…This underpins the need for correct identification of these fungi, and further studies are clearly required to better understand their distribution, ecology and pathogenicity. * The species has also been described by Yamaoka et al (1998) andAoshima (1965).…”