Stewart, J.I.2015-07-142015-07-141983Stewart, J.I. (1983). Crop Yields and Returns under Different Soil Moisture Regimes. East African Agricultural And Forestry Journal, 427-438. https://kalroerepository.kalro.org/handle/0/43540012-8325https://kalroerepository.kalro.org/handle/0/4354Reserch begun in Kenya in 1977 under the Dryland Cropping Systems Research Project is described. In Machakos District, intercropping of maize and beans [Phaseolus vulgaris] was studied under line source irrigation. Yields of both spp. increased linearly with applied water until requirements were satisfied at 250 mm for beans; maize water requirements were not satisfied at 438 mm and the estimated water requirement for max. yield was 589 mm. With 450 mm water yields were 5.92 and 2.5 t/ha for pure strands of maize and beans, resp., compared with 4.98 + 0.7 t in the intercrop. Intercropping was only advantageous when rainfall was more than 325 mm with an early onset of rains. In a 2nd trial at Katumani maize yields increased with application of 40 kg N/ha, but higher rates did not increase yields further. In fertile conditions, grain production began when water use was 218 mm, but without N fertilizer 298 mm was required. Grain production also depended on plant density; with 154 mm rainfall plots of 20 000 plants/ha produced grain but higher density plots did not. In better rainfall seasons 40 000 or even 60 000 plants/ha produced max. grain yields.enhttp://creativecommons.org/licenses/by/3.0/Journal ContributionCropsYieldsSoilSoil moisture