Does the Latent Period of Leaf Fungal Pathogens Reflect Their Trophic Type? A Meta-Analysis of Biotrophs, Hemibiotrophs, and Necrotrophs

Abstract

We performed a meta-analysis to search for a relation between the trophic type and latent period of fungal pathogens. The pathogen incubation period and the level of resistance of the hosts were also investigated. This ecological knowledge would help us to more efficiently regulate crop epidemics for different types of pathogens. We gathered latent period data from 103 studies dealing with 51 fungal pathogens of the three major trophic types (25 biotrophs, 15 hemibiotrophs, and 11 necrotrophs), representing 2,542 mean latent periods. We show that these three trophic types display significantly different latent periods. Necrotrophs exhibited the shortest latent periods (<100 degree-days [DD]), biotrophs had intermediate ones (between 100 and 200 DD), and hemibiotrophs had the longest latent periods (>200 DD). We argue that this relation between trophic type and latent period points to two opposing host exploitation strategies: necrotrophs mount a rapid destructive attack on the host tissue, whereas biotrophs and hemibiotrophs avoid or delay the damaging phase. We query the definition of hemibiotrophic pathogens and discuss whether the length of the latent period is determined by the physiological limits inherent to each trophic type or by the adaptation of pathogens of different trophic types to the contrasting conditions experienced in their interaction with the host.

Subcellular Roles of Glutathione in Mediating Plant Defense during Biotic Stress

“…Thus, the plant does not activate its defense or reduces its defenses to an extent that it keeps the fungal infection under control. Some biotrophic fungi can also turn into necrotrophic fungi during their life span [13,17,69,70]. Necrotrophic interactions are characterized by the complete destruction of the plant by the fungi.…”

“…Others, such as biotrophic fungi or bacteria live in a mutualistic relationship with the plant from which both partners benefit without killing each other [12][13][14][15]. Some fungi switch from a biotrophic to a necrotrophic relationship during their lifetime [16,17]. Bacteria have a similar relationship with the plant and can be necrotrophic, biotrophic, or both.…”

Different community compositions between obligate and facultative oomycete plant parasites in a landscape-scale metabarcoding survey

“…It is important to note that these categories describe life phases rather than the microorganisms t hemselves (Lorang 2019). Many hemibiotrophic intermediate states between biotrophy and necrotrophy are recognised (Spanu and Panstruga 2017), varying in the length of the latent period, the degree of inflicted damage and the susceptibility of the host (Précigout et al 2020). In addition, most species of hemibiotrophs can live as saprotrophs in the soil, even in the absence of the host plant (Lifshitz and Hancock 1983), and recently, species of Pythium have been shown to play an important role in litter degradation (Kramer et al 2016).…”

Predicting Lifestyle from Positive Selection Data and Genome Properties in Oomycetes

“…Following the hyphal stage and massive host colonization, there is a reproductive, mainly sporulating stage which needs to be tightly regulated. The latent period between infection and sporulation has been shown recently to correlate to different pathogenic lifestyles in leaf pathogens [ 77 ]. A widely diversified family of proteins in the oomycetes that take part in transcriptional activation and help regulate sporulation are Myb transcription factors [ 78 , 79 ].…”