Deciphering the role of the phenylpropanoid metabolism in the tolerance of Capsicum annuum L. to Verticillium dahliae Kleb.
Verticillium dahliae is an economically relevant soilborne pathogen that causes vascular wilt in several crops, including pepper (Capsicum annuum). Fungal infection is usually visualized as a vascular browning, likely due to the onset of phenylpropanoid metabolism, which also seems to play a crucial role in the tolerance of some pepper varieties. In the current work, the potential function of distinct phenylpropanoid derivatives (suberin, lignin and phenolic compounds) in the pepper tolerance response against V. dahliae, was investigated. Histochemical and biochemical analyses ruled out suberin as a key player in the pepper-fungus interaction. However, changes observed in lignin composition and higher deposition of bound phenolics in infected stems seemed to contribute to the reinforcement of cell walls and the impairment of V. dahliae colonization. Most importantly, this is the first time that the accumulation of the hydroxycinnamic acid amide N-feruloyltyramine was reported in pepper stems in response to a vascular fungus. Fungitoxic activity for that hydroxycinnamate-tyramine conjugate was demonstrated as well.
Universidade da Coruña, Grupo de Investigación en Bioloxía Evolutiva, Departamento de Bioloxía Animal, Bioloxía Vexetal e Ecoloxía, Facultade de Ciencias, Centro de Investigaciones Científicas Avanzadas (CICA), 15071 A Coruña, Spain.
Marta
M
Novo
Universidade da Coruña, Grupo de Investigación en Bioloxía Evolutiva, Departamento de Bioloxía Animal, Bioloxía Vexetal e Ecoloxía, Facultade de Ciencias, Centro de Investigaciones Científicas Avanzadas (CICA), 15071 A Coruña, Spain.
Cristina
C
Silvar
Universidade da Coruña, Grupo de Investigación en Bioloxía Evolutiva, Departamento de Bioloxía Animal, Bioloxía Vexetal e Ecoloxía, Facultade de Ciencias, Centro de Investigaciones Científicas Avanzadas (CICA), 15071 A Coruña, Spain.
Fuencisla
F
Merino
Universidade da Coruña, Grupo de Investigación en Bioloxía Evolutiva, Departamento de Bioloxía Animal, Bioloxía Vexetal e Ecoloxía, Facultade de Ciencias, Centro de Investigaciones Científicas Avanzadas (CICA), 15071 A Coruña, Spain.
Teresa
T
Martínez-Cortés
Department of Biochemistry and the Department of Energy's Great Lakes Bioenergy Research Center, The Wisconsin Energy Institute, University of Wisconsin, WI 53726 Madison, USA; State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, 510640 Guangzhou, China.
Fachuang
F
Lu
Department of Biochemistry and the Department of Energy's Great Lakes Bioenergy Research Center, The Wisconsin Energy Institute, University of Wisconsin, WI 53726 Madison, USA.
John
J
Ralph
Universidade da Coruña, Grupo de Investigación en Bioloxía Evolutiva, Departamento de Bioloxía Animal, Bioloxía Vexetal e Ecoloxía, Facultade de Ciencias, Centro de Investigaciones Científicas Avanzadas (CICA), 15071 A Coruña, Spain. Electronic address: federico.pomar@udc.es.
Federico
F
Pomar
D002212:Capsicum / Q000378:metabolism / Q000382:microbiology*; D002473:Cell Wall / Q000378:metabolism; D003373:Coumaric Acids / Q000378:metabolism; D008031:Lignin / Q000378:metabolism; D010636:Phenols / Q000378:metabolism; D010935:Plant Diseases / Q000382:microbiology*; D020005:Propanols / Q000378:metabolism*; D014439:Tyramine / Q000031:analogs & derivatives / Q000378:metabolism; D020172:Verticillium / Q000472:pathogenicity*
D003373:Coumaric Acids; D010636:Phenols; D020005:Propanols; C439395:1-phenylpropanol; C074004:feruloyltyramine; D008031:Lignin; D014439:Tyramine
Bound phenolics; Fungitoxic activity; Lignin; N-feruloyltyramine; Pepper; Verticillium wilt