Comparative photosynthetic attributes of emmer and modern wheats in response to water and nitrogen supply

A field study was conducted with the aim to elucidate photosynthetic responses of five emmer hulled wheat ( Triticum turgidum ssp. dicoccum) accessions to 30 (N-limited) and 100 kg(N) ha –1 (N-sufficient) conditions at control and drought stress (irrigation after 30–40% and 60–70% depletion of available soil water, respectively). Chlorophyll (Chl) a and Chl b concentrations of the emmer wheats remained unchanged but net photosynthetic rate and dry mass increased and decreased, respectively, when received a sufficient amount of N. Smaller drought-induced decreases in Chl concentration, membrane stability index, and dry mass were concomitant to a greater decrease in intercellular CO 2 concentration of emmer compared to the durum ( Triticum turgidum ) and bread wheats ( Triticum aestivum ). The lack of negative effect of insufficient N on Chl concentration and dry mass of emmer wheat suggests that this type of wheat possesses an obvious potential for organic farming.