Paper Reviewed
Perez-Lopez, U., Miranda-Apodaca, J., Mena-Petite, A. and Muñoz-Rueda, A. 2014. Responses of nutrient dynamics in barley seedlings to the interaction of salinity and carbon dioxide enrichment. Environmental and Experimental Botany 99: 86-99.

Perez-Lopez et al. (2014) begin their intriguing paper by noting that no prior studies have evaluated the interactive effects of atmospheric CO2 enrichment and soil salinity enhancement on nutrient acquisition, partitioning and use efficiencies of various crop plants; and, therefore, they decided to "take the leap," as it were, and do so themselves, selecting barley (Hordeum vulgare L. cv. Iranis) as their "plant of interest." And what exactly did they do?

According to the four Spanish scientists, they measured uptake and translocation rates, nutrient contents, and nutrient concentrations in whole plants and in individual plant organs, as well as whole-plant nutrient use efficiency and nutrient selectivity in barley seedlings grown under non-saline (0 mM NaCl) and saline (80, 160 and 240 mM NaCl) conditions at ambient (350 ppm) or elevated (700 ppm) atmospheric CO2 concentrations. And what did they find?

Perez-Lopez et al. report that their study "provided evidence that elevated CO2 caused adjustments in root size and activity that could change the nutrient uptake and transport efficiency to match the demand for the nutrients analyzed." And they indicate that "under combined conditions of salt stress and elevated CO2, barley seedlings were able to maintain increased uptake and translocation rates for almost all nutrients," with the end result that "this ability allowed the seedlings to adapt to a higher demand under elevated CO2 and to grow more rapidly by allocating more photo-assimilates to the roots, which increased root growth and active nutrient uptake and translocation."