Hemibiotrophs

Hemibiotrophs are the spectrum of plant pathogens, including bacteria, oomycete and a group of plant pathogenic fungi that keep its host alive while establishing itself within the host tissue, taking up the nutrients with brief biotrophic-like phase.^[1][2] It then, in later stages of infection switches to a necrotrophic life-style, where it rampantly kills the host cells, deriving its nutrients from the dead tissues.^[3]

This mode of interaction, in which initial biotrophy followed by a switch to necrotrophy, has been observed in the fungal model Magnaporthe oryzae (rice blast fungus) and other pathogens such as many Colletotrichum spp. (often called anthracnose diseases, e.g. Colletotrichum lindemuthianum), Southern corn leaf blight (Bipolaris maydis) and, Zymoseptoria tritici (syn. Mycosphaerella graminicola, leaf blotch of wheat).^[4][5][6] Collectively, they represent some of the most destructive plant parasites, causing huge economic losses, threatening global food security.^[7]

A spectrum of hemibiotrophic plant pathogens, including the bacterium Pseudomonas syringae and the oomycete Phytophthora infestans (potato blight), also exhibit characteristics of both biotrophs and necrotrophs and thus are called hemibiotrophs, depending on the stages of their life cycle.^{[citation needed]}