Over the past few decades it has become well established that semiochemical compounds, including volatile organic compounds (VOCs), are emitted from plants after biotic or abiotic stress. These compounds can have important roles in plant defence. Indeed, investigations carried out on tobacco plants infected by the causal agent of powdery mildew showed an increased emission of methyl-jasmonate (MeJA), cis-jamone (CisJA), methyl-salicylate (MeSA), and E-2-hexenal and β-ocimene, with respect to healthy control plants. The aim of the present study was to investigate the effects of the induction triggered by these compounds in tobacco (Nicotiana tabacum cv Havana 425)–oidium [Erysiphe cichoracearum DC, sin. Golovinomyces cichoracearum (DC) V.P. Heluta] and tobacco–aphid (Myzus persicae Sulzer) interactions. Exogenous treatments with BTH (functional analogue of salicylic acid), MeJA and E-2-hexenal protected tobacco plants against both the biotic stresses, while treatments with β-ocimene reduced aphid infestations, but increased powdery mildew infections. Moreover, BTH treatments induced in tobacco an accumulation of PR1 protein, a marker of the SA-dependent defence pathway, while MeJA treatment induced NICTABA transcript accumulation, a response typically related to the JAdependent defence pathway in tobacco. Screening analyses of semiochemical emissions from MeJA-treated plants supplied further information regarding the jasmonate metabolic pathway. The emission of some terpenes was seen, which were negligible in control plants. Thorough examinations will be carries out to elucidate the roles of these molecules against the pathogen and the insect.
Interaction of tobacco-oidium-aphids: role of some semiochemicals in SA-dependent and JA-dependent induced resistance
QUAGLIA, Mara;FABRIZI, MARIO;ZADRA, Claudia;VOLPE, Daniela;EDERLI, Luisa;MARUCCHINI, Cesare;ZAZZERINI, Antonio
2009
Abstract
Over the past few decades it has become well established that semiochemical compounds, including volatile organic compounds (VOCs), are emitted from plants after biotic or abiotic stress. These compounds can have important roles in plant defence. Indeed, investigations carried out on tobacco plants infected by the causal agent of powdery mildew showed an increased emission of methyl-jasmonate (MeJA), cis-jamone (CisJA), methyl-salicylate (MeSA), and E-2-hexenal and β-ocimene, with respect to healthy control plants. The aim of the present study was to investigate the effects of the induction triggered by these compounds in tobacco (Nicotiana tabacum cv Havana 425)–oidium [Erysiphe cichoracearum DC, sin. Golovinomyces cichoracearum (DC) V.P. Heluta] and tobacco–aphid (Myzus persicae Sulzer) interactions. Exogenous treatments with BTH (functional analogue of salicylic acid), MeJA and E-2-hexenal protected tobacco plants against both the biotic stresses, while treatments with β-ocimene reduced aphid infestations, but increased powdery mildew infections. Moreover, BTH treatments induced in tobacco an accumulation of PR1 protein, a marker of the SA-dependent defence pathway, while MeJA treatment induced NICTABA transcript accumulation, a response typically related to the JAdependent defence pathway in tobacco. Screening analyses of semiochemical emissions from MeJA-treated plants supplied further information regarding the jasmonate metabolic pathway. The emission of some terpenes was seen, which were negligible in control plants. Thorough examinations will be carries out to elucidate the roles of these molecules against the pathogen and the insect.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
