Rubisco genes expression and pigment synthesis at early stages of development of wheat cultivar dajti under saline stress conditions

Photosynthetic rate is highly correlated with the amount of Rubisco, thus naturally occur-ring rubiscos with superior properties can be exploited to improve wheat productivity. Local wheat cultivar Dajti was created in Albania through conventional selection practices, and was evaluated as resistant toward environmental stresses. Here we present results on the expression of rubisco genes (rbcL/S) and concentration of chl pigments under saline stress. For these, seeds of cultivar Dajti were kept at 4ᵒC for 24 h and were allowed to germinate in Petri dishes supplied with water only at 22ᵒC for 3 days; further supplied with Hoagland solution for 14 days, and finally were grown in Hoagland culture modified with different concentrations of NaCl (50, 100, and 200 mM). Chl pigments were extracted and measured from leaves of plantlets two and three weeks after the application of stress conditions following the standart DMSO protocol, calculations were made based on Arnon’s equations; Excel and SPSS were used to statistically evaluate the results. Total RNA was extracted from leaf material at 0–3–6–10–24–72 h following saline treatment, and specific RT-PCRs were developed to control the expression of Rubisco genes (rbcL/S). Synthesis of new rubisco gene products compared to controls was evidenced; synthesis of chl pigments was not impacted significantly by salt concentrations, even though it was reduced over the time of exposure (from week to week). Since photosynthetic rate is highly correlated with the amount of Rubisco, the presence of new transcripts of rubisco genes could be interpreted as plant’s response for the regulation of the amount of the enzyme in order to keep the pigment’s amount in leaves as stable as possible in shortly applied saline stress conditions.