Allometric relations in legume – grass mixture under drought

The study of allometric relations could interpret the competitive capability of different species that grow in mixture. The grow up way of canopy was measured in 1:1 mixture of Medicago sativa with Festuca arundinacea. The experiment was contacted in Drama, in northern Greece, in semiarid climate and infertile soil without any fertilizer apply, during the period from May to July in the years 1996 and 1997. Two levels of water regimes were used: A. only rainfed B. supplementary irrigation. Leaf area, dry weight of the leaves and shoots dry were measured in pure and mixed culture for each species. Leaf Area Ratio (LAR), Leaf Weight Ratio (LWR) and Specific Leaf Weight (SLW) were calculated. Results shown that, during summer season, the LAR was decreased in plants grown in rainfed conditions, compared to plants grown under irrigation. The cultivation in mixture influenced the LAR only under irrigation but in different way for each species. The LAR was increased in Festuca arundinacea and was decreased in Medicago sativa.