Growth, water relations and nutrition of three grassland annuals as affected by drought.
3 winter annuals were grown under glasshouse conditions to evaluate their behaviour under varying soil moisture stress and population density. The reduction in total biomass was significant when soil water potential was decreased from field capacity to -3 bar. Trifolium subterraneum appeared to be the least sensitive to soil moisture stress. Erodium botrys had the lowest transpiration rate and the lowest total water use. Bromus mollis used the greatest amount of water and also had the highest total biomass. Increases in plant population density did not affect E. botrys and B. mollis but the total biomass of T. subterraneum increased significantly. Total nutrient uptake was reduced by increasing soil moisture stress.