Photosynthetic and transpiration rates of Olea europaea subsp. sylvestris and Rhamnus lycioides as affected by water deficit and mycorrhiza

Abstract

This study examined the effect of mycorrhizal colonization with Glomus intraradices on physiological parameters and foliar nutrient concentrations in Olea europaea L. subsp. sylvestris and Rhamnus lycioides L. seedlings subjected to well-watered or drought-stressed conditions. Under drought stress, mycorrhizal O. europaea seedlings showed significantly higher photosynthetic and transpiration rates, stomatal conductance and foliar P concentration than its similarly-sized non-mycorrhizal counterpart. The intrinsic water use efficiency (photosynthetic rate to stomatal conductance ratio) was not change in O. europaea and decreased in R. lycioides seedlings due to mycorrhizal colonization under both well-watered and drought-stress conditions.