R-BPMV-Mediated Resistance to Bean pod mottle virus in Phaseolus vulgaris L. Is Heat-Stable but Elevated Temperatures Boost Viral Infection in Susceptible Genotypes

Abstract

In the context of climate change, elevated temperature is a major concern due to the impact on plant–pathogen interactions. Although atmospheric temperature is predicted to increase in the next century, heat waves during summer seasons have already become a current problem. Elevated temperatures strongly influence plant–virus interactions, the most drastic effect being a breakdown of plant viral resistance conferred by some major resistance genes. In this work, we focused on the R-BPMV gene, a major resistance gene against Bean pod mottle virus in Phaseolus vulgaris. We inoculated different BPMV constructs in order to study the behavior of the R-BPMV-mediated resistance at normal (20 °C) and elevated temperatures (constant 25, 30, and 35 °C). Our results show that R-BPMV mediates a temperature-dependent phenotype of resistance from hypersensitive reaction at 20 °C to chlorotic lesions at 35 °C in the resistant genotype BAT93. BPMV is detected in inoculated leaves but not in systemic ones, suggesting that the resistance remains heat-stable up to 35 °C. R-BPMV segregates as an incompletely dominant gene in an F2 population. We also investigated the impact of elevated temperature on BPMV infection in susceptible genotypes, and our results reveal that elevated temperatures boost BPMV infection both locally and systemically in susceptible genotypes.

Fine-mapping and evolutionary history of R-BPMV, a dominant resistance gene to Bean pod mottle virus in Phaseolus vulgaris L.

“…Consequently, identifying which TNL from common bean encodes the R-BPMV R gene remains an important task for the future. In addition, the resistance mediated by R-BPMV is heat-stable up to 35°C, making this R gene even more attractive in the context climate change (Meziadi et al 2021).…”

“…In common bean, the I resistance cluster is a multi-parasitic resistance cluster (Meziadi et al 2016) phaseolicola and the fungus Colletotrichum lindemuthianum (Fisher andKyle 1994, 1996;Crute and Pink 1996;Morales and Singh 1997;Geffroy et al 2008;Bello et al 2014;Tock et al 2017) . Recently, the dominant R-BPMV gene, conferring resistance against Bean pod mottle virus (BPMV, genus Comovirus, family Comoviridae), was also linked to the I cluster (Pflieger et al 2014;Meziadi et al 2021). Like other comoviruses, BPMV has a bipartite-positive strand RNA genome consisting of RNA1 and RNA2, which are separately encapsidated in isomeric particles (Ghabrial 1982).…”