SUMMARYField experiments made for 2 years on a deep vertisol under semi-arid conditions showed that soil-surface evaporation control by mulching with rice straw or transpiration suppression by foliar application of kaolin or atrazine increased the yield of grain sorghum. These materials decreased soil moisture depletion and thus increased water-use efficiency. Application of one irrigation at the boot-leaf stage was beneficial. No additional advantage was noted with two irrigations, one given 45 days after seeding and the other at anthesis.