Increasing forest loss worldwide from invasive pests requires new trade regulations

Loss of forests due to non-native invasive pests (including insects, nematodes, and pathogens) is a global phenomenon with profound population, community, ecosystem, and economic impacts. We review the magnitude of pest-associated forest loss worldwide and discuss the major ecological and evolutionary causes and consequences of these invasions. After compiling and analyzing a dataset of pest invasions from 21 countries, we show that the number of forest pest invasions recorded for a given country has a significant positive relationship with trade (as indicated by gross domestic product) and is not associated with the amount of forested land within that country. We recommend revisions to existing international protocols for preventing pest entry and proliferation, including prohibiting shipments of non-essential plants and plant products unless quarantined. Because invasions often originate from taxa that are scientifically described only after their introduction, current phytosanitary regulations – which target specific, already named organisms – are ineffective

Proceedings of the IUFRO Working Party 2.02.15 “Breeding and Genetic Resources of Five-Needle Pines” Conference held from September 19 to 23, 2006, Valiug, Romania

<p>An international IUFRO WP 2.02.15 conference was held from 19-23 September, 2006, at Valiug, namely at the Claris Hotel placed just<br />in the heart of an outstanding multi-age natural beech forest from south-western Carpathians.<br />The conference was attended by 46 delegates representing nine countries. A total of 21 oral and eight poster presentations were given. Reports were presented on variety of research topics, all of them connected to the five needle-pines.</p

Endophyte-mediated resistance against white pine blister rust in Pinus monticola

Abstract Induced resistance responses, including fungal endophyte-mediated resistance, have been well studied in both agricultural crops and grass systems. Yet, the effect of these processes and symbionts in forest trees is poorly known. Fungal endophytes have been found in all conifer forest systems examined to date and have been hypothesised to be involved in resistance-mediated responses. However, in the absence of functional studies the influence of these endophytes on the extended phenotype of the host plant is unclear. In this study we demonstrate that fungal endophytes from Pinus monticola were effective at increasing survival in host plants against the exotic pathogen Cronartium ribicola, which is responsible for the devastating disease called white pine blister rust. Seedlings previously inoculated with fungal endophytes lived longer than endophyte-free seedlings and also showed some reduction in white pine blister rust disease severity. This endophyte-mediated resistance was found to be effective over time, indicating persistence, and is hypothesised to be a form of induced resistance. Overall, this suggests fungal endophytes may play a determinative role in the structure of biological communities and could provide a useful alternative or ancillary management tool for combating pests and diseases.

Disease resistance in whitebark pine and potential for restoration of a threatened species

Societal impact statement Forests world‐wide are being negatively affected by non‐native, invasive pathogens and pests, and some tree species face uncertain futures. To retain these species as components of future forests, the rare genetic resistance that exists needs to be identified and harnessed. The applied tree improvement program for whitebark pine (Pinus albicaulis), a threatened (in the United States) and endangered (in Canada) keystone species in many forests in western North America, provides an example of what can be accomplished in a relatively short timeframe. The level and frequency of resistance vary by location, and this information will be used to implement the national restoration plan. Summary Forest trees face serious threats from non‐native diseases and pests, often causing high mortality of both the existing trees and regeneration. Developing populations with genetic resistance can help restore forests and retain affected species. Resistance programs have historically focused on species of high economic importance; however, the threats to species of little direct economic value that provide other important ecosystem services are also great. We examined the frequency, level, and geographic variation in genetic resistance to white pine blister rust in the threatened Pinus albicaulis (whitebark pine), a keystone species in high‐elevation ecosystems in western North America. In the two trials reported here, 2‐year‐old seedling progeny of 225 whitebark pine parent trees were inoculated with two geographic sources of the fungal pathogen Cronartium ribicola and evaluated over 5 years for an array of resistance traits. The trials focused primarily on parent trees from the Oregon and Washington populations. We found unexpectedly high levels of quantitative resistance in some seedling families and populations, in stark contrast to levels observed in similar resistance programs with other North American white pine species such as Pinus monticola and Pinus lambertiana. The level of resistance found in some whitebark pine populations provides optimism about potential recovery efforts for this species. Restoration efforts are underway by government agencies, tribes, and non‐government organizations in both the United States and Canada. These efforts may help boost support for applied genetic resistance programs in other forest tree species severely affected by non‐native pathogens or pests