TY - JOUR

T1 - Deciphering Molecular Host-Pathogen Interactions During Ramularia Collo-Cygni Infection on Barley

AU - Lemcke, René

AU - Sjökvist, Elisabet

AU - Visentin, Stefano

AU - Kamble, Manoj

AU - James, Euan K.

AU - Hjørtshøj, Rasmus

AU - Wright, Kathryn M.

AU - Avrova, Anna

AU - Newton, Adrian C.

AU - Havis, Neil D.

AU - Radutoiu, Simona

AU - Lyngkjær, Michael F.

N1 - Publisher Copyright: Copyright © 2021 Lemcke, Sjökvist, Visentin, Kamble, James, Hjørtshøj, Wright, Avrova, Newton, Havis, Radutoiu and Lyngkjær.

PY - 2021

Y1 - 2021

N2 - Ramularia collo-cygni is the causal agent of Ramularia leaf spot disease (RLS) on barley and became, during the recent decades, an increasing threat for farmers across the world. Here, we analyze morphological, transcriptional, and metabolic responses of two barley cultivars having contrasting tolerance to RLS, when infected by an aggressive or mild R. collo-cygni isolate. We found that fungal biomass in leaves of the two cultivars does not correlate with their tolerance to RLS, and both cultivars displayed cell wall reinforcement at the point of contact with the fungal hyphae. Comparative transcriptome analysis identified that the largest transcriptional differences between cultivars are at the early stages of fungal colonization with differential expression of kinases, calmodulins, and defense proteins. Weighted gene co-expression network analysis identified modules of co-expressed genes, and hub genes important for cultivar responses to the two R. collo-cygni isolates. Metabolite analyses of the same leaves identified defense compounds such as p-CHDA and serotonin, correlating with responses observed at transcriptome and morphological level. Together these all-round responses of barley to R. collo-cygni provide molecular tools for further development of genetic and physiological markers that may be tested for improving tolerance of barley to this fungal pathogen.

AB - Ramularia collo-cygni is the causal agent of Ramularia leaf spot disease (RLS) on barley and became, during the recent decades, an increasing threat for farmers across the world. Here, we analyze morphological, transcriptional, and metabolic responses of two barley cultivars having contrasting tolerance to RLS, when infected by an aggressive or mild R. collo-cygni isolate. We found that fungal biomass in leaves of the two cultivars does not correlate with their tolerance to RLS, and both cultivars displayed cell wall reinforcement at the point of contact with the fungal hyphae. Comparative transcriptome analysis identified that the largest transcriptional differences between cultivars are at the early stages of fungal colonization with differential expression of kinases, calmodulins, and defense proteins. Weighted gene co-expression network analysis identified modules of co-expressed genes, and hub genes important for cultivar responses to the two R. collo-cygni isolates. Metabolite analyses of the same leaves identified defense compounds such as p-CHDA and serotonin, correlating with responses observed at transcriptome and morphological level. Together these all-round responses of barley to R. collo-cygni provide molecular tools for further development of genetic and physiological markers that may be tested for improving tolerance of barley to this fungal pathogen.

KW - fungal pathogen

KW - Hordeum vulgare

KW - host defense

KW - metabolite responses

KW - Pathogen response pathways

KW - Ramularia

KW - Transcriptome (RNA-seq)

KW - transmission electron microscopy

U2 - 10.3389/fpls.2021.747661

DO - 10.3389/fpls.2021.747661

M3 - Journal article

C2 - 34745181

AN - SCOPUS:85118697776

VL - 12

JO - Frontiers in Plant Science

JF - Frontiers in Plant Science

SN - 1664-462X

M1 - 747661

ER -