Plant pathogenesis: Toward multidimensional understanding of the microbiome

Abstract Single pathogen‐targeted disease management measure has shown drawbacks in field efficacy under the scenario of global change. An in‐depth understanding of plant pathogenesis will provide a promising solution but faces the challenges of the emerging paradigm involving the plant microbiome. While the beneficial impact of the plant microbiome is well characterized, their potential role in facilitating pathological processes has so far remained largely overlooked. To address these unsolved controversies and emerging challenges, we hereby highlight the pathobiome, the disease‐assisting portion hidden in the plant microbiome, in the plant pathogenesis paradigm. We review the detrimental actions mediated by the pathobiome at multiple scales and further discuss how natural and human triggers result in the prevalence of the plant pathobiome, which would probably provide a clue to the mitigation of plant disease epidemics. Collectively, the article would advance the current insight into plant pathogenesis and also pave a new way to cope with the upward trends of plant disease by designing the pathobiome‐targeted measure

Evolution of tinea capitis in the Nanchang area, Southern China: a 50-year survey (1965-2014)

Tinea capitis remains a common public health problem worldwide especially in developing areas. Aetiologic agents and clinical pattern vary with geography and history of socioeconomic conditions. Three community surveys and a prospective study were carried out over the past 50 years (1965-2014) in the Qingyunpu District of Nanchang, Southern China. Clinical presentation and spectrum of aetiological agents were monitored to understand the evolution of tinea capitis. In 1965 favus was highly epidemic and Trichophyton schoenleinii presented as the overwhelming aetiological agents of scalp infection in the study area, with a prevalence of 3.41% of the population. During a governmental campaign to eliminate tinea capitis initiated in mid of 1960s, favus was successfully controlled and the prevalence decreased to less than 0.01% in 1977. After that period, clinical presentation and spectrum of fungi changed with social development. Trichophyton schoenleinii was replaced by Trichophyton violaceum and Trichophyton mentagrophytes. Nowadays, the species corresponds with a dominant black dot type of tinea capitis in the Nanchang area. The prevalence of causative agents of tinea capitis is not only related to geography but also to socioeconomic factors. Multiple factors have to be considered for the management for control of this disease

<i>Aspergillus cvjetkovicii </i>protects against phytopathogens through interspecies chemical signalling in the phyllosphere

Resident microbiota produces small molecules that influence the chemical microenvironments on leaves, but its signalling roles in pathogen defence are not yet well understood. Here we show that Aspergillus cvjetkovicii, enriched in rice leaf microbiota, subverts Rhizoctonia solani infections via small-molecule-mediated interspecies signalling. 2,4-Di-tert-butylphenol (2,4-DTBP), identified as a key signalling molecule within the Aspergillus-enriched microbiota, effectively neutralizes reactive oxygen species-dependent pathogenicity by switching off bZIP-activated AMT1 transcription in R. solani. Exogenous application of A. cvjetkovicii and 2,4-DTBP demonstrated varying degrees of protective effects against R. solani infection in diverse crops, including cucumber, maize, soybean and tomato. In rice field experiments, they reduced the R. solani-caused disease index to 19.7–32.2%, compared with 67.2–82.6% in the control group. Moreover, 2,4-DTBP showed activity against other rice phytopathogens, such as Fusarium fujikuroi. These findings reveal a defensive strategy against phytopathogens in the phyllosphere, highlighting the potential of symbiotic microbiota-driven neutralization of pathogenicity.</p