Water Uptake and Germination of Leguminous Seeds in Soils of Changing Matric and Osmotic Water Potential

Abstract

Water uptake and germination rate of chickpea and pea seeds were compared under changing water potentials in sand and soil aggregate columns and osmotic solutions. The final water uptake and germination were the same in all cases for a given water potential, but the rates were lower for seeds planted in sand columns, probably due to mechanical constraints imposed on the swelling seed by the dense sand, since the capillary conductivity, and the diffusivity to water of the sand were very high. The area of the seed in contact with soil is not of importance if soil aggregates are small as compared to the seeds but increases in importance when the seeds and the soil aggregates are of the same size and at low water potentials.