Co-infection by Soil-Borne Fungal Pathogens Alters Disease Responses Among Diverse Alfalfa Varieties

Abstract

Fusarium oxysporum f. sp. medicaginis (Fom) and Rhizoctonia solani (Rs) are the major soil-borne fungal pathogens that pose severe threats to commercial alfalfa production in China. However, the effects of Fom and Rs co-infection on alfalfa and whether co-infection alters disease resistance responses among diverse varieties remain unknown. A collection of 80 alfalfa varieties (Medicago sativa) originated from seven countries were used to study the effects of Fom and Rs co-infection on alfalfa and host resistance responses. The co-infection resulted in more severe disease and reductions in growth and biomass allocation across varieties in comparison with either single infection by Fom or Rs; in addition, root morphology was much more strongly altered by the co-infection. Principal component analysis based on all plant traits showed that varieties under the co-infection were related to the single infection by Rs, being separated from Fom, and hierarchical clustering found differential response patterns among varieties upon co-infection compared with either single infection, with most varieties being highly susceptible to the co-infection. Furthermore, varieties that were most resistant to either single infection were not effective to co-infection, and there was no individual variety with resistance to both pathogens singly and co-infected. This study reveals for the first time that the co-infection by Fom and Rs alters disease resistance responses among diverse alfalfa varieties and provides useful information for developing alfalfa varieties with resistance to the co-occurrence of different soil-borne pathogens.

Co-infection of Fusarium aglaonematis sp. nov. and Fusarium elaeidis Causing Stem Rot in Aglaonema modestum in China

“…The co-infection of Fusarium oxysporum f. sp. medicaginis and Rhizoctonia solani in commercial alfalfa production has shown severe disease incidence, growth reduction, and biomass allocation across different varieties compared to a single infection ( Fang et al, 2021 ). In addition, several studies have shown that being co-infected by different soil-borne pathogens has a significant increase in disease development compared with a single infection ( Peters and Grau, 2002 ).…”

Coinfection and in vitro interaction of Lasiodiplodia pseudotheobromae and Pestalotiopsis mangiferae associated with dieback in branches of mango (Mangifera indica) Manila variety, in Veracruz, Mexico

“…Using directed sampling, ten trees with dieback symptoms (gummosis, rotting of evaluaciones realizadas se han centrado en la coinfección de virus-virus, bacterias-hongos y hongohongo (Tollenaere et al, 2016). Algunos estudios han demostrado que las coinfecciones fúngicas aumentan la prevalencia y severidad de las enfermedades y la producción de esporas (Fang et al, 2021;Susi et al, 2015). Sin embargo, puede haber inhibición de un fitopatógeno hacia otro (Orton y Brown 2016;Lerch-Olson y Robertson, 2020).…”

“…En los últimos años, diversos estudios se han enfocado a investigar las enfermedades vegetales provocadas por co-infecciones de hongos fitopatógenos Mexican Journal of PHYTOPATHOLOGY Revista Mexicana de FITOPATOLOGÍA Advance online publication, 2022 processes of mutualism, antagonism, coexistence, among others (Fang et al, 2021). In addition, the severity of diseases caused by co-infections of phytopathogens depends on various factors, mainly growth rate, virulence, metabolite production, interactions, host, among others (Müller et al, 2012;Boddy, 2016;Luo et al, 2017).…”

“…Las ramas de mango co-inoculadas con L. pseudotheobromae y P. mangiferae presentaron una mayor severidad de la muerte descendente en conjunto en comparación con las infecciones individuales. Las interacciones fúngicas son complejas e involucran procesos de mutualismo, antagonismo, coexistencia, entre otros (Fang et al, 2021). Además, la severidad de las enfermedades provocadas por co-infecciones de fitopatógenos depende de diversos factores, destacando la tasa de crecimiento, virulencia, producción de metabolitos, interacción, hospedero, entre otros (Müller et al, 2012;Boddy, 2016;Luo et al, 2017).…”

“…The assessments that have been conducted so far have focused on virus-virus, bacterium-fungus and fungus-fungus coinfections (Tollenaere et al, 2016). Some studies have shown that fungal coinfections increase the prevalence and severity of diseases and spore production (Fang et al, 2021;Susi et al, 2015). However, plant pathogens may inhibit each other (Orton and Brown 2016;Lerch-Olson and Robertson, 2020).…”