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Field tests were carried out to examine the efficacy of soil solarization in conjunction with amendments (urea at 20 Kg N ha-l and farmyard manure) for the control of wilt (Fusarium oxysporum f. sp. cumini) of cumin (Cuminum cyminum) and dry root rot (Macrophomina phaseolina) of clusterbean (Cyamopsis tetragonoloba). During the summer of 1987, solarization of soil by covering it with transparent polyethylene sheets for 15 days greatly reduced the population of the two soilborne pathogens at 0-30 cm depth. As a result, significant reductions in the incidence of wilt, dry root rot and weed populations, and improvements in seed yields were recorded in solarized plots. Soil amendments extended the effectiveness of solarization by restricting the rebound of Fusarium, even after two successive crops of cumin, compared to solar heating alone. Similarly Macrophomina populations did not increase significantly after one crop of clusterbean. Populations of these pathogens were also reduced considerably merely by the natural heating of the moistened bare soil after amendments. These results suggest a new approach to disease control by the application of summer irrigation in hot arid regions.