Influence of wastewater application and fertilizer use on growth, photosynthesis, nutrient homeostatis, yield and heavy metal accumulation in okra (Abelmoschus esculentus L. Moench).

The scarceness of freshwater assets is a serious problem in semi-arid zones and marginal quality water is increasingly being used in agriculture. This study aimed at evaluating the physico-chemical and biological risks on irrigated soils of treated wastewater, the nutrient supply and the effect on okra plant. A pot experiment based on completely randomized block design was conducted with Treated Wastewater (TW) and inorganic fertilizers to observe a comparative effect on biochemical characters using Okra var. Nidhi. The physico-chemical analysis of the TW showed that it was rich in total suspended and dissolved solids with large amount of BOD and COD. The higher amount of Cl-, Ca++, Mg++ and K+ were also present in the effluent. The heavy metal (Cd, Cr, Ni and Pb) content in TW is comparatively more than groundwater (GW). The values of these heavy metals were slightly higher in the soil irrigated with TW. The effluent severely affects crop plants and soil properties when used for irrigation. The growth parameters, photosynthetic characteristics, chlorophyll content, yield and nutrient homeostatis were analyzed during different growth periods in all treatments. All the parameters were found to increase due to wastewater application. Among the fertilizer treatments, N120 proved optimum, N90 deficient and N150 proved as luxury dose. The seeds accumulated Cd and Ni but their level was under permissible limits. Thus, it may be concluded that wastewater may be used profitably for the cultivation of okra.