Possible contribution of cell-wall-bound ferulic acid in drought resistance and recovery in triticale seedlings

Studies were undertaken to estimate whether the presence of free and cell-wall-bound ferulic acid in leaf tissues can support drought resistance and its recovery under rehydration. An experiment was carried out on two genotypes of winter triticale: Lamberto and Ticino, at the propagation phase. Lamberto exhibited high content of ferulic acid bound with carbohydrates of the cell-wall under drought and rehydration. The markedly better parameters of chlorophyll fluorescence for this variety under both treatments correlated strongly and positively with the high contents of cell-wall-bound ferulic acid. The photosynthetic apparatus of Lamberto, in relation to Ticino, proved to be the more efficient after 4 weeks of drought treatment. The after-effects of soil drought better elicited the function disturbances of the photosynthetic apparatus in Ticino, which did not fully recover in comparison to Lamberto. Ferulic acid covalently bound to carbohydrates of the cell wall may act as a light filter limiting mesophyll penetration under drought conditions and can also support drought adaptation by down-regulation of leaf growth. The observed increase in the content of cell-wall-bound ferulic acid, as a response to water deficit in the leaf, could be one of the protective mechanisms induced by drought conditions. The ability to accumulate phenolic compounds in dehydrated leaves might be an additional and reliable biochemical parameter indicating the resistance of plants to drought stress.