The development and potential role of mycoherbicides for forestry

Abstract

With increasing intensification of forest management and limited options for control of competing vegetation, there is need for research on alternative vegetation management methods, including biological control. Most forest weeds in Canada are native species with useful as well as detrimental roles, and therefore classical biological control with introduced natural enemies generally cannot be considered. At present, use of native fungal pathogens, or mycoherbicides, is one of the most promising approaches, and recent advancements in agriculture indicate that effective, site-specific controls using mycoherbicides are possible. Mycoherbicide use in forestry appears attractive because of the likelihood of fewer off-target effects than present vegetation management methods and because it could provide either selective controls for specific weeds or broad spectrum controls.Vegetation management in forestry has some unique aspects which will make the development of biological controls different from that in agriculture. There are many indigenous plant pathogens that are potential mycoherbicides, but their efficacy will need to be enhanced by adjuvants, stress treatments, and integration with other vegetation control practices. Currently, at three Canadian institutions and several other locations worldwide, there are research programs on biological control of forest vegetation.

Occurrence ofPhoma argillaceaonRubus spectabilisin British Columbia and an evaluation of its potential as a forest weed biological control agent

“…However, persistence of herbicides in the environment, water contamination following aerial spraying, and runoff from land treated with herbicides (Selim et al 1989) have prompted the need for alternative, more environmentally friendly, and socially accepted methods for controlling forest weeds. Biological control of forest weeds using inundative applications of fungal pathogens may provide such an alternative (Wall et al 1992;Shamoun 2000;Evans et al 2001).…”

“…(salmonberry) is a native perennial deciduous shrub in North America (Oleskevich et al 1996) and is considered to be one of the top 20 forest weeds in Canada (Wall et al 1992). Salmonberry has a negative impact on successful establishment and growth of young conifers, such as Douglas-fir (Pseudotsuga menziesii (Mirb.)…”

Forest pathogens: friend or foe to biodiversity?

“…Because red alder is not susceptible to the rot, sufficiently vigorous root growth presents a physical obstruction to spread of the pathogen (Thies and Sturrock 1995). Regarding suppression, it is also possible to make use of the biocontrol potential inherent in phytopathogens for management of forest weeds (Wall et al 1992). Chondrostereum purpureum (Pers.…”

Biological Vegetation Management: An Alternative To Chemical Pesticides

“…bioherbicide against unwanted vegetation has been considered in Europe (Scheepens and Hoogerbrugge 1989;De Jong et al 1990) and in Canada (Wall 1990(Wall , 1994Wall et al 1992). Extensive study to develop a safe and effective biological vegetation management tool has been conducted in Québec, Canada, since 1992 (Gosselin 1998;Goulet 1998).…”