Biological control of ophiostoma novo-ulmi, the causal agent of Dutch elm disease

榆树是北美城市景观的一个重要经济特征。它们优雅的树干和宽阔的树枝为加拿大许多城市街道提供了荫凉和庇护。目前，加拿大的城镇估计有70万棵榆树，但与上个世纪城市规划者种植的数百万棵榆树相比，这一数字有所减少。病原真菌Ophiostoma novo-ulmi选择性地杀死了北美种植的大部分榆树，令城市规划者感到沮丧。目前还没有对这种特别具有攻击性的植物病原体进行有效控制，荷兰榆病仍然没有得到控制。我们正在努力通过开发一种基于病毒的可传播疾病控制来开发对这种病原体的生物防治。在我们对这种真菌的功能基因组学和种群遗传学研究的基础上，我们正在努力开发一系列真菌特异性靶标，以找到削弱这种侵略性病原体的方法。我们认为，控制真菌可以通过感染病原体双链RNA(DsRNA)亚病毒来实现，这种病毒已经被修改为靶向对这种真菌的致病性至关重要的基因。如果在新生稻瘟病菌中证实了针对可传播低毒力的改进靶标，则可能为许多真菌病原体的生物防治提供一种新的途径。

Elms are an economically important feature of urban landscapes across North America. Their elegant trunks and wide branches provide shade and shelter along many Canadian city streets. There are currently an estimated 700,000 elm trees in cities and towns across Canada however this has been reduced from the many millions of trees planted by urban planners during the past century. The pathogenic fungus Ophiostoma novo-ulmi has frustrated urban planners by selectively killing most of the elm trees planted in North America. There is currently no effective control for this particularly aggressive phytopathogen and Dutch elm disease remains unchecked. We are working towards developing a biological control for this pathogen through the development of a transmissible viral-based disease control. Building upon our research on the functional genomics and population genetics of this fungus we are working towards developing a series of fungal-specific targets to find ways to debilitate this aggressive pathogen. We propose that control of the fungus may be achieved by infecting the pathogen with a double-stranded RNA (dsRNA) hypovirus that has been modified to target genes essential to the pathogenicity of this fungus. The improved targeting of transmissible hypovirulence, if proven in O. novo-ulmi, could provide a new approach to the biological control of many fungal pathogens.