Drought-induced anatomical modifications of barley (Hordeum vulgare L.) leaves: an allometric perspective

•Anatomical leaf traits in barley were allometrically related to leaf length.•Exposure of plants to a period of drought resulted in xeromorphic anatomical modifications in newly produced leaves.•Most of the drought-induced modifications were partly explained by reduction in leaf length.•Both allometric and plastic components account for drought-induced leaf xeromorphism in barley.