Eleonora Barilli1, Diego Rubiales2, Carmine Amalfitano3, Antonio Evidente4, Elena Prats2. 1. Institute for Sustainable Agriculture, CSIC, Córdoba, Spain. ebarilli@ias.csic.es. 2. Institute for Sustainable Agriculture, CSIC, Córdoba, Spain. 3. Agrarian Department, University of Naples Federico II, Portici, Italy. 4. Department of Chemical Science, University of Naples Federico II, Naples, Italy.
Abstract
MAIN CONCLUSION: Systemic acquired resistance elicitors, BTH and BABA, reduce rust penetration in pea through phytoalexins pathway but differing in their mode of action. It has been previously shown that rust (Uromyces pisi) infection can be reduced in pea (Pisum sativum) by exogenous applications of systemic acquired resistance elicitors such as BTH and BABA. This protection is known to be related with the induction of the phenolic pathway but the particular metabolites involved have not been determined yet. In this work, we tackled the changes induced in phytoalexin content by BTH and BABA treatments in the context of the resistance responses to pea rust. Detailed analysis through high-performance liquid chromatography (HPLC) showed qualitative and quantitative differences in the content, as well as in the distribution of phytoalexins. Thus, following BTH treatment, we observed an increase in scopoletin, pisatin and medicarpin contents in all, excreted, soluble and cell wall-bound fraction. This suggests fungal growth impairment by both direct toxic effect as well as plant cell wall reinforcement. The response mediated by BTH was genotype-dependent, since coumarin accumulation was observed only in the resistant genotype whereas treatment by BABA primed phytoalexin accumulation in both genotypes equally. Exogenous application to the leaves of scopoletin, medicarpin and pisatin lead to a reduction of the different fungal growth stages, confirming a role for these phytoalexins in BTH- and BABA-induced resistance against U. pisi hampering pre- and postpenetration fungal stages.
MAIN CONCLUSION: Systemic acquired resistance elicitors, BTH and BABA, reduce rust penetration in pea through phytoalexins pathway but differing in their mode of action. It has been previously shown that rust (Uromyces pisi) infection can be reduced in pea (Pisum sativum) by exogenous applications of systemic acquired resistance elicitors such as BTH and BABA. This protection is known to be related with the induction of the phenolic pathway but the particular metabolites involved have not been determined yet. In this work, we tackled the changes induced in phytoalexin content by BTH and BABA treatments in the context of the resistance responses to pea rust. Detailed analysis through high-performance liquid chromatography (HPLC) showed qualitative and quantitative differences in the content, as well as in the distribution of phytoalexins. Thus, following BTH treatment, we observed an increase in scopoletin, pisatin and medicarpin contents in all, excreted, soluble and cell wall-bound fraction. This suggests fungal growth impairment by both direct toxic effect as well as plant cell wall reinforcement. The response mediated by BTH was genotype-dependent, since coumarin accumulation was observed only in the resistant genotype whereas treatment by BABA primed phytoalexin accumulation in both genotypes equally. Exogenous application to the leaves of scopoletin, medicarpin and pisatin lead to a reduction of the different fungal growth stages, confirming a role for these phytoalexins in BTH- and BABA-induced resistance against U. pisi hampering pre- and postpenetration fungal stages.
Entities:
Keywords:
Elicitors; Fungal impairment; Pea rust; Phytoalexins
Authors: A Arfaoui; A El Hadrami; Y Mabrouk; B Sifi; A Boudabous; I El Hadrami; F Daayf; M Chérif Journal: Plant Physiol Biochem Date: 2007-04-21 Impact factor: 4.270
Authors: Ma Angeles Castillejo; Ana M Maldonado; Eliane Dumas-Gaudot; Mónica Fernández-Aparicio; Rafael Susín; Rubiales Diego; Jesús V Jorrín Journal: BMC Genomics Date: 2009-07-03 Impact factor: 3.969