A survey of Ophiostoma species vectored by Hylastes ater to pine seedlings in New Zealand

Abstract

Ecological studies in New Zealand require consideration of the impact of exotic (introduced) organisms from disparate environments. A survey of Ophiostoma species isolated and identified from Pinus radiata stumps, the bark beetle Hylastes ater collected from these stumps and from P. radiata seedlings following sublethal damage by H. ater, was undertaken in 10 reforestation sites in New Zealand. Nine Ophiostoma species were isolated and identified in this survey. Ophiostoma galeiformis and Ophiostoma huntii were isolated most frequently from all the substrates sampled. Ophiostoma floccosum, Ophiostoma setosum, Leptographium procerum and Leptographium truncatum were also isolated from stumps, damaged seedlings and beetles. Ophiostoma quercus was only isolated from stumps and beetles and Ophiostoma ips only from beetles. A strong relationship between the severity of H. ater feeding damage, and the presence and number of species of Ophiostoma was found. Eight Ophiostoma species were transmitted by H. ater to P. radiata seedlings in laboratory transmission experiments. From the results of this field survey and the laboratory experiments we confirm that H. ater is a vector of Ophiostoma species to P. radiata seedlings in New Zealand.

Ophiostomatoid fungi isolated from three different pine species in Argentinian Patagonia

“…Previous works in Chile (Zhou et al., ) reported Grosmannia huntii associated with Hylastes ater on Pinus radiata . This interaction has also been reported from New Zealand (Reay, Thwaites, & Farrell, ) and Argentina (Gómez, Greslebin, & Rajchenberg, ) affecting young pine seedlings. In the present study, G. huntii has been isolated as a saprobe from Hylastes ater galleries and stained timber, occurring only in Neuquén Province (Northern Patagonia).…”

Predicting sapstain and degrade in fallen trees following storm damage in a Pinus radiata forest

“…Such insects can carry fungal spores on their surface or in specialised structures such as mycangia which evolved in bark beetles as a means of transporting spores of mutualistic fungi (Bleiker et al, 2009;Grebennikov and Leschen, 2010;Masuya et al, 2009;Reay et al, 2005Reay et al, , 2006b. However, in this study, although the incidence of beetle colonisation increased with time, no difference was found in the proportion of sapstain present in discs as a function of beetle colonisation until the last sample time, 67 weeks after the storms in rooted trees.…”

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

“…The fungus was originally described from roots of non-native Pinus species in South Africa, infested by Hylastes angustatus Herbst, presumably introduced from Europe ( Wingfield and Marasas 1983;Wingfield 1985). Similarly, L. truncatum has repeatedly been found on non-native pines in New Zealand Reay et al 2005;Thwaites et al 2005;Kim et al 2011), and with T. piniperda introduced into Canada from Europe (Hausner et al 2005). However, L. truncatum does not appear to be a common associate of beetles in Europe, as it has only been reported from the UK and Spain (Romón et al 2007) on this continent.…”