Using pathogen nutrient acquisition strategy to explain the occurrence of fungal and oomycete diseases in wild plants

Wild plant diseases impact host fitness and ecosystem functions, threatening food security and ecological integrity. Fungal and oomycete pathogens differ in nutrient acquisition strategies (i.e. biotroph versus necrotroph), and these strategies shape pathogen reproduction, infection patterns and host defences. While existing reviews have outlined these differences, a unifying framework leveraging these nutrient acquisition strategies to explain disease patterns across diverse abiotic and biotic drivers is lacking. To address this, we explore how these strategies determine pathogen responses to abiotic and biotic factors and associated disease risks. Biotrophic pathogens typically show a unimodal relationship with temperature and precipitation, with optimal ranges for each. Necrotrophic pathogen infections usually increase under high temperature, drought or excessive precipitation. Nitrogen additions generally elevate disease risk for both, although biotrophs may benefit more owing to reliance on host nutrients. Biodiversity loss exacerbates the disease load, particularly for diseases caused by biotrophic pathogens. Herbivory suppresses biotrophic but promotes necrotrophic pathogens, whereas arbuscular mycorrhizal fungi reduce necrotrophic rather than biotrophic pathogens. We propose that incorporating data on pathogen nutrient acquisition strategy into plant disease models will improve predictions of fungal and oomycete disease outbreaks under future climate scenarios and support the development of targeted management policies. This article is part of the theme issue 'Wild plant pathosystems'.