Phenol metabolism of two cultivars of durum wheat (Triticum durum Desf.) as affected by ozone and flooding stress

Abstract

To compare the phenolic responses under oxidative stressors, plants of two Italian cultivars of durum wheat (Claudio and Mongibello) were (a) exposed to ozone (O3) (80 ppb, 5 hr/day for 70 consecutive days), with the aim to investigate the changes of phenolic compound contents in their leaves, or (b) flooded (seven consecutive days). Plants showed O3‐induced visible injury, but their photosynthetic performance was not affected by the pollutant. Specifically, Claudio showed a higher O3 tolerance than Mongibello. The major value of the present study is undoubtedly the pioneering investigation of phenolic metabolism of durum wheat under O3. We identified 12 foliar phenolic compounds in all leaf samples (i.e. controls, exposed to O3 and flooded): ten phenolic acids, a flavanol (catechin hydrate) and a phenolic aldehyde (syringaldehyde). Overall, O3 exposure resulted in accumulations of phenolic compounds, especially in Claudio. These responses can be likely considered a fine‐regulated repair process that equipped Claudio stressed plants with an antioxidant system capable of scavenging oxidative stress. Different phenolic variations were found in flooded plants, suggesting that phenolic response to environmental constraints is stress specific. Our study confirms that investigations and characterization of specific phenolic profiles of crop cultivars under oxidative stress may be helpful in breeding programmes.

Transient Waterlogging Events Impair Shoot and Root Physiology and Reduce Grain Yield of Durum Wheat Cultivars

“…However, this phenomenon was likely due to the activation/depression of enzymatic and non-enzymatic antioxidants, adopted by plants to regulate the stress response and signaling [4,42]. Among antioxidants, the key role of phenylpropanoids in the response of durum wheat to waterlogging has been previously indicated by [10].…”

“…Accordingly, our findings clearly showed that Emilio Lepido was more tolerant to waterlogging, whereas Svevo was more sensitive even with a waterlogging duration shorter than 20 days. To the best of our knowledge, any other durum wheat cultivar from Claudio and Svevo has been investigated for agronomic waterlogging tolerance [5,10]. However, high-yielding genotypes of common wheat were more affected by waterlogging than lower yielding types, because plants were not able to maintain high tillering, as showed by [20].…”

“…From a physiological point of view, excess water accumulation in the root zone can induce osmotic stress and disrupt cell ion homeostasis. To cope with such stressful conditions, plants tend to accumulate compounds called osmoprotectans (such as free amino acids, non-structural carbohydrates, and quaternary ammonium substances), as their accumulation may decrease the osmotic potential [9,10]. Next, the impaired root functioning under waterlogging affects the physiological responses of the shoots, particularly the carbon fixation.…”

“…Waterlogging may induce partial stomatal closure that, in turn, could constrain internal CO 2 levels and limit carbon fixation [11,12]. Additionally, photosynthesis rates can also be inhibited by non-stomatal factors, e.g., oxidative injury [10] caused by reactive oxygen species (ROS) like hydrogen peroxide (H 2 O 2 ), superoxide radicals, and hydrogen radicals which impair mesophyll conductance [13], and harm photosystem II (PSII), causing cellular damage and leaf chlorosis related to chlorophyll degradation [14,15].…”

TECHNOLOGICAL CHARACTERISTICS OF CHICKPEA (Cicer arietinum L.) CULTIVARS GROWN UNDER NATURAL CONDITIONS

“…Experimental data on technological characteristics of chickpea cultivars were subjected to analysis of variance by using JMP 13.0 (SAS Institute Inc., Cary, NC, USA) statistical software. Significant means were compared with the use of Tukey's test (p≤0.05) (Steel and Torrie, 1980;Chen et al, 2020).…”