Physiological effects in genotype-dependent plants of winter triticale growing in previously salinized soil

Studies were conducted to assess the effect of long-term soil salinity on adult plants of four winter triticale genotypes grown 500 days after the application of 100 mM NaCl. Morphological features (straw length, total height, number of tiers, weight and number of grains) and chlorophyll a fluorescence parameters were analyzed. Additionally, the content of pigments in leaves (chlorophyll, flavonoids and anthocyanins) and kernel proteins (peroxiredoxin, glutenins and gliadins), was assessed, which allowed for the identification of defense mechanisms activated under the influence of stress. Additionally, Raman and microscopic analysis were performed. The results of the study showed that long-term soil salinization significantly limits plant growth, which is manifested by a decrease in straw length and total height, and damage of photosynthetic apparatus, as evidenced by a decrease in Fv/Fm and PI values. An increase in flavonoid, anthocyanin and protein levels was observed, which indicates the mobilization of protective mechanisms. The DH3 line showed the highest tolerance to salt stress, maintaining photosynthetic efficiency at a level similar to the control, and a smaller decrease in morphological features. Raman measurements indicated only minor biochemical modifications in this line, as evidenced by the calculated ratio of band intensities associated with starch-specific signals. Chlorophyll a fluorescence parameters and pigment content can serve as markers for the selection of genotypes with increased tolerance to long-term salinity, which is of importance in the context of plant breeding in areas exposed to soil degradation. To our knowledge, the study presents the first evidence of peroxiredoxin on the protein level in triticale grains and its flag leaf cross-sections.