Open AccessNitrogen modulation of Medicago truncatula resistance to Aphanomyces euteiches depends on plant genotype
Author(s) -
Thalineau Elise,
Fournier Carine,
Gravot Antoine,
Wendehenne David,
Jeandroz Sylvain,
Truong HoaiNam
Publication year - 2018
Publication title -
molecular plant pathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.945
H-Index - 103
eISSN - 1364-3703
pISSN - 1464-6722
DOI - 10.1111/mpp.12550
Subject(s) - medicago truncatula , biology , oomycete , sclerotium , genotype , botany , shoot , pathogen , resistance (ecology) , plant defense against herbivory , horticulture , microbiology and biotechnology , gene , agronomy , bacteria , symbiosis , genetics
Summary Nitrogen (N) availability can impact plant resistance to pathogens by the regulation of plant immunity. To better understand the links between N nutrition and plant defence, we analysed the impact of N availability on Medicago truncatula resistance to the root pathogen Aphanomyces euteiches . This oomycete is considered to be the most limiting factor for legume production. Ten plant genotypes were tested in vitro for their resistance to A. euteiches in either complete or nitrate‐deficient medium. N deficiency led to enhanced or reduced susceptibility depending on the plant genotype. Focusing on four genotypes displaying contrasting responses, we determined the impact of N deficiency on plant growth and shoot N concentration, and performed expression analyses on N‐ and defence‐related genes, as well as the quantification of soluble phenolics and different amino acids in roots. Our analyses suggest that N modulation of plant resistance is not linked to plant response to N deprivation or to mechanisms previously identified to be involved in plant resistance. Furthermore, our studies highlight a role of glutamine in mediating the susceptibility to A. euteiches in M. truncatula .