Abstract
Drought is one of the major environmental stresses that adversely affects crop growth and productivity worldwide. The effect of inoculation with Azospirillum lipoferum on growth, yield, water status, osmoprotectant, antioxidant system and grain anatomy of wheat plants under drought stress conditions was investigated. The plants exposed to the drought stress exhibited a significant reduction in growth, grains yield, relative water content and leaf photosynthetic pigments, as well as alterations in grain anatomy. However, the treatment with A. lipoferum alleviated the stress generated by drought and improved the above-mentioned parameters. Drought stress increased proline, protein, soluble carbohydrates, relative membrane permeability and activities of antioxidant enzymes (SOD and POX). The antioxidant enzymes, phenols and grain anatomy exhibited changes in response to A. lipoferum inoculation in the absence or presence of drought stress. Our data suggest that inoculation with A. lipoferum could protect wheat plants from the harmful effects of drought stress through changes in the antioxidant defense system.