Common bean varieties demonstrate differential physiological and metabolic responses to the pathogenic fungusSclerotinia sclerotiorum

Abstract

Plant physiology and metabolism are important components of a plant response to microbial pathogens. Physiological resistance of common bean (Phaseolus vulgaris L.) to the fungal pathogen Sclerotinia sclerotiorum has been established, but the mechanisms of resistance are largely unknown. Here, the physiological and metabolic responses of bean varieties that differ in physiological resistance to S. sclerotiorum are investigated. Upon infection, the resistant bean variety A195 had a unique physiological response that included reduced photosynthesis and maintaining a higher leaf surface pH during infection. Leaf metabolomics was performed on healthy tissue adjacent to the necrotic lesion at 16, 24, and 48 hr post inoculation, and 144 metabolites were detected that varied between A195 and Sacramento following infection. The metabolites that varied in leaves included amines/amino acids, organic acids, phytoalexins, and ureides. The metabolic pathways associated with resistance included amine metabolism, uriede-based nitrogen remobilization, antioxidant production, and bean-specific phytoalexin production. A second experiment was conducted in stems of 13 bean genotypes with varying resistance. Stem resistance was associated with phytoalexin production, but unlike leaf metabolism, lipid changes were associated with susceptibility. Taken together, the data supports a multifaceted, physiometabolic response of common bean to S. sclerotiorum that mediates resistance.

Advances of Metabolomics in Fungal Pathogen–Plant Interactions

“…A multiomic approach combining RNA sequencing, GC-MS-based metabolomics, and chemical genomics was performed on the S. sclerotiorum -infected resistant and susceptible soybean cultivars. The results identified an increase in bioactive jasmonate JA-Ile ((+)-7-iso-jasmonoyl-L-isoleucine), which scavenges reactive oxygen species and reprograms the phenylpropanoid pathway to increase antifungal activities in the resistant soybean [79].…”

Integrated Transcriptomic and Un-Targeted Metabolomics Analysis Reveals Mulberry Fruit (Morus atropurpurea) in Response to Sclerotiniose Pathogen Ciboria shiraiana Infection

“…In rice blast disease, the photoassimilates were shifted to mannitol and glycerol for mycelial growth [30]. The bean metabolites that varied in leaves included amines/amino acids, organic acids, phytoalexins, and ureides during Sclerotinia sclerotiorum infection [31]. Terpene down-regulation triggers pathogen defense responses in transgenic orange [32].…”

Effect of Trichoderma velutinum and Rhizoctonia solani on the Metabolome of Bean Plants (Phaseolus vulgaris L.)

“…Plant-pathogen interactions are complex phenomena and affect the metabolism of each partner differently. Plant defense strategies against their pathogens are diverse, including the induction of expression of defense genes and also the production of antifungal compounds called phytoalexins, that include flavonoids, phenols, glucosinolates, terpenes and alkaloids with a broad spectrum of antimicrobial functions [27,28]. In this work, we have investigated the changes in metabolite profiles of bean plants cultivated for forty-five days in the presence of T. velutinum and/or R. solani .…”