IMPACT OF DIFFERENT WATER HARVESTING TECHNIQUES ON SOIL MOISTURE CONTENT AND YIELD COMPONENTS OF SORGHUM

Rainwater harvesting (RWH) could be the best alternative for water resources, which affects the yield and productivity of Sorghum (Sorghum bicolor L.). Therefore, field studies were conducted in North Kordofan area, Western Sudan, on a sandy clay loam soil during 2012 and 2013 growing seasons, in which the effects of five water harvesting techniques (WHTs) for growing sorghum including mulching, intercropping, stone barriers, crescent and L-shape were investigated. The moisture content of the soil was measured at three periods before crop sowing (P1), at mid-season (P2) and after harvest (P3) and at four soil depths (0-15, 15-30, 30-60 and 60-90 cm). The results revealed that, the soil and plant parameters were significantly influenced by the WHTs during both growing seasons through improving the structure, infiltrability, and water storage capacity of the soil in relation to the control. The variability of the soil moisture content (SMC) and plant parameters increased during the drier season 2012 and decreased during the wetter season 2013. Soil depth, measurement period and their interaction had highly significant effects on SMC during both growing seasons. Differences among the WHTs were more obvious in the topsoil layer (0-30 cm) with no significant differences below 30 cm depth. Straw mulching conserved more moisture within one soil profile, particularly at the medium and lower depths (30-90 cm). It also consistently captured more run-off water than the other techniques; at all stages of plant growth, in both growing seasons followed by earth and stone bunding. This was clearly reflected by better crop establishment and yield components of sorghum, hence generate higher gross returns. In conclusion, the study revealed the potential advantages of WHTs for semi-arid zones and in particularly for Northern Kordofan, Sudan with reference to the rationale for adopting WHTs and enhance sorghum yield.