Inoculation and co-inoculation of lettuce and arugula hydroponically influence nitrogen metabolism, plant growth, nutrient acquisition and photosynthesis.

The objective of this study was to investigate the effects of single and combined inoculations of and on lettuce and arugula grown in a hydroponic system. The study was carried out in a greenhouse and was designed in randomized blocks with five replications. The treatments consisted of inoculation with and and co-inoculation with and via nutrient solution. An increase in the length and fresh mass of the shoot and leaf chlorophyll concentrations of arugula and lettuce was observed under co-inoculations of and . Greater length, fresh mass and volume of the lettuce root system were observed under the co-inoculations of and in arugula under the inoculations of and Greater nitrate reductase activity was detected in leaves, and lower nitrate accumulation was detected in lettuce and arugula under inoculations with and . The greatest accumulation of N, P, K, Ca and Mg in the lettuce shoot was obtained under inoculation with , and . Co-inoculation with and was the most efficient combination for increasing the growth, nutrient acquisition and functioning of nitrogen metabolism in arugula lettuce plants.