methyl-jasmonate and epsilon-viniferin

Topics: Acetates; Benzofurans; beta-Cyclodextrins; Cyclopentanes; Glucosides; Oxylipins; Plant Roots; Resorcinols; Resveratrol; Stilbenes; Vitis

This study was conducted to characterize the forms of disease resistance induced by methyl jasmonate (MeJA) in harvested grape berries and to evaluate the impact of the induced resistance on fruit quality. The results showed that MeJA treatment at concentrations from 10 to 100μmol/L could effectively induce disease resistance against Botrytis cinerea and reduce disease incidence in grape berries. The induced disease resistance was tightly associated with increased H2O2 generation, enhanced expression of the defense-related gene VvNPR1.1 and accumulation of stilbene phytoalexins such as tran-resveratrol and its oligomer (trans-)ε-viniferin. The expression of the defense-related gene and synthesis of phytoalexins in 10μmol/L MeJA-treated grape berries were only significantly enhanced upon inoculating the berries with B. cinerea, whereas the 50 or 100μmol/L of MeJA treatment directly induced these defense responses. Hence, we deduce that the low concentration of MeJA (10μmol/L) triggered a priming defense mechanism, while higher concentrations of MeJA (50 or 100μmol/L) directly activated defense responses, thus enhancing disease resistance in grape berries. Moreover, the primed grape berries maintained higher contents of soluble sugars and higher DPPH radical scavenging activity and reducing power compared with those expressing direct defense responses. These results indicate that priming of defense is a cost-effective strategy to protect harvested grape berries from B. cinerea infection in terms of minimizing quality loss.

Topics: Acetates; Benzofurans; Botrytis; Cyclopentanes; Disease Resistance; Fruit; Gene Expression Regulation; Hydrogen Peroxide; Oxylipins; Plant Growth Regulators; Resveratrol; Stilbenes; Vitis

Methyl jasmonate, jasmonic acid and chitosan were tested as elicitors on cell suspension cultures obtained from Vitis vinifera cv Italia to investigate their effect on stilbene production. Stilbene accumulation in the callus, grown under nonelicited conditions, was also investigated. Calli and cell suspensions were obtained in a B5 culture medium supplemented with 0.2 mg L(-1) NAA and 1 mg L(-1) KIN. Stilbene determination was achieved by HPLC/DAD/MS. Whereas callus biosynthesized only piceid, cell suspensions elicited with jasmonates produced several stilbenes, mainly viniferins. In suspended cells, methyl jasmonate and jasmonic acid were the most effective in stimulating stilbene biosynthesis, whereas chitosan was less effective; in fact, the amount of stilbenes obtained with this elicitor was not significantly different from that obtained for the control cells. The maximum production of total stilbenes was at day 20 of culture with 0.970 and 1.023 mg g(-1) DW for MeJA and JA, respectively.

Topics: Acetates; Benzofurans; Cells, Cultured; Chitosan; Cyclopentanes; Oxylipins; Plant Growth Regulators; Plant Stems; Resorcinols; Resveratrol; Stilbenes; Vitis