EFFECT OF WASTEWATERS ON PLANT-GROWTH AND SOIL PROPERTIES

Effects of wastewaters on plant growth and soil properties were studie d in a pot experiment. Mean biomass ranged from 159 to 210 g per pot f or maize and from 165 to 212 g per pot for sorghum in different water salinity treatments. Mean dry matter yield ranged between 28.9 to 38.3 and 34.9 to 50.4 g per pot in different water salinity treatments for maize and sorghum crops, respectively. The crop yield showed signific ant increase with increase in water salinity. This was presumably due to the nutrients present in wastewaters, especially the nitrogen. Plan t yield decreased slightly at water salinity level of 2330 mg L-1 (TDS ), indicating that high water salinity can neutralize the beneficial e ffects of nutrients in wastewaters. Soil salinity and sodicity increas ed significantly with corresponding increase in water salinity and sod icity (r values of 0.98 (maize) and 0.98 (sorghum) for soil salinity, and 0.96 (maize) and 0.95 (sorghum) for SAR of soils). The interaction between crop and water treatments was significant for soil salinity ( an LSD of 0.48 at p = 0.05) and SAR of soil (an LSD 2.55 at p = 0.05). Overall, the soil salinity and sodicity was significantly more in sor ghum than maize. The results showed that wastewaters can successfully be used to grow corn and sorghum as forage crops, provided 15 to 20% e xcess water is applied to meet leaching requirements to maintain soil salinity within acceptable limits for optimal agricultural production.