Investigation of Lotus corniculatus L. adaptation under limited irrigation

The purpose of this study was to investigate the adaptation of a population of Lotus corniculatus in conditions of limited irrigation. Plants from a natural population were harvested and transplanted into plastic pots. After a period of plant adjustment two irrigation treatments were applied: a) irrigation to the point of field capacity and b) limited irrigation. During the growing period of 2013, the water potential (Ψ), osmotic potential (Ψs) and stomatal conductance (gs) were measured under field conditions, while the turgor potential (Ψρ) and the relative water content (RWC) were calculated. It was found that for the same Ψ, plants under limited irrigation showed higher water deficit and stomatal conductance and positive turgor, which remained almost constant throughout the growing season. The maintenance of turgor under water stress could be due to the fact that the reduction of Ψs was proportional to the reduction of Ψ. The above results suggest that L. corniculatus shows plasticity and is able to grow under limited irrigation, while maintaining high relative turgor potential and relative water content.