Hydrology: Current Research

Assessing the Yields and Nutrient Uptake of Okra Abelmoschus Esculentu Using Diluted Stabilized Wastewater for Irrigation in South -Western Nigeria

Abstract

Adewoye AO, Okunade DA and Adekalu KO

Growth, crop yields and nutrient uptake of Okra [Abelmoschus esculentus (L.) Moench] irrigated with different mix proportions of stream water to partially treated sewage effluent (0:100; 25:75; 50:50; 75:25; 100:0) under furrow system were determined. There were four replicates of each treatment and the 100% stream water served as the control, the stream water has little effluent discharges along the downstream. The 75% treated sewage effluent gave the highest fruit yield of 10.5 t/ha while the 100% stream water gave the lowest fruit yield of 5.40 t/ha. The highest dry matter yield of 9.8 t/ha was obtained with 100% partially treated sewage. There was no significant difference among the treatments in the number of leaves and plant heights. The 100% partially treated sewage effluent however gave significantly (P<0.05) higher leave area index and plant girth than other treatments while the 50% partially treated sewage had significantly (P<0.05) higher fruit moisture content at harvest. Analysis of the plant indicated that maximum nutrient uptake occurred in 25:75% stream water: sewage effluent treatment and the nutrient content of the crop in all the treatments compared with acceptable limits in common crops. There was little or no trace of odour on the water or trace of bacteria in the harvested crop since the water has been treated through waste water stabilization ponds. The sewage resulted in higher P, K, and Cu content of the soil. This study shows that okra can safely be grown in the study area with partially treated sewage effluent but would be best when mixed in 25:75% of stream water to partially treated sewage and the soil leached intermittent to prevent Cu and macro-nutrient build-up.