title: Effect of salicylic acid and structurally related compounds in the accumulation of phytoalexins in cotyledons of common bean (Phaseolus vulgaris L.) cultivars.
abstract: In the present work, isoflavonoid phytoalexin production in response to the application of salicylic acid in cotyledons of four common bean (Phaseolus vulgaris) cultivars (SA) was evaluated. The time-course and dose-response profiles of the induction process were established by quantifying the isoflavonoids by HPLC. Cotyledons of anthracnose-resistant cultivars induced by SA produced substantially higher phytoalexin contents as compared to the susceptible ones. In addition, maximum levels of phytoalexins (50-100 fold increases) were reached between 96 and 144 h, and when a concentration of SA from 3.62 to 14.50 mM was used. The observations also indicate that there was a relatively good correlation between the phytoalexin contents and the inhibitory effect against C. lindemuthianum; the higher antifungal activity was observed during the first 48 hours for extracts from cotyledons treated with SA at 1.45 and 3.62 mM, and between 96 and 144 h after induction. Finally, compounds structurally related to SA (dihydro-quinazolinones and some imines) showed a strong elicitor effect. Moreover, induced extracts from cotyledons treated with these potential elicitors, besides the properly elicitors, displayed a weak to moderated antifungal activity. These compounds may be considered good candidates for developing of new phytoprotectants. Furthermore, phytoalexin-eliciting substances may contribute for selecting disease resistant cultivars.
authors.affiliation: Grupo de Química de los Productos Naturales y los Alimentos, Escuela de Química, Facultad de Ciencias, Universidad Nacional de Colombia-Sede Medellín, Calle 59ª 63-020 Autopista Norte, P.O. Box 3840, Medellín, Colombia. dldurango@unal.edu.co
authors.forename: Diego
authors.initials: D
authors.lastname: Durango
authors.forename: Natalia
authors.initials: N
authors.lastname: Pulgarin
authors.forename: Fernando
authors.initials: F
authors.lastname: Echeverri
authors.forename: Gustavo
authors.initials: G
authors.lastname: Escobar
authors.forename: Winston
authors.initials: W
authors.lastname: Quiñones
mesh_terms: D000935:Antifungal Agents / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D020231:Colletotrichum / Q000187:drug effects; D018548:Cotyledon / Q000187:drug effects / Q000378:metabolism*; D060467:Disease Resistance; D007529:Isoflavones / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D027805:Phaseolus / Q000187:drug effects / Q000378:metabolism*; D010935:Plant Diseases / Q000382:microbiology; D010936:Plant Extracts / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D010937:Plant Growth Regulators / Q000494:pharmacology / Q000502:physiology; D020156:Salicylic Acid / Q000494:pharmacology*; D012717:Sesquiterpenes / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology; D000094162:Phytoalexins
chemical_list: D000935:Antifungal Agents; D007529:Isoflavones; D010936:Plant Extracts; D010937:Plant Growth Regulators; D012717:Sesquiterpenes; D020156:Salicylic Acid; D000094162:Phytoalexins