Enhancing Okra [Abelmoschus Esculentus (L.) Moench] Yield With Biosolid Mass Derived From Faecal Sludge: A Sustainable Approach

Abstract

This study evaluates the effects of biosolid mass (BM) obtained from a faecal sludge treatment plant (FSTP) in Bhongir, Telangana, on Okra (Abelmoschus esculentus (L.) Moench) crop yields. The FSTP, situated in Bhuvanagiri (17.49° N, 78.91° E), has a capacity to treat 15 KLD of faecal sludge and began operations in 2020. The study measured seed germination rates, plant growth, pod length, pod weight, nutrient values and heavy metals (found to be within the limits as per norms). Okra plants grown in an experimental soil bed (ESB) with biomass compost (BMC) exhibited significantly improved growth attributes compared to those grown in a control soil bed (CSB). The germination rates were 37% for CSB and 39 % for ESB. Plants in CSB grew to heights between 0.6 and 0.7 meters, while those in ESB reached 1 to 1.2 meters. The pod weights during the first and second harvests on CSB were 519 g and 830 g, respectively, while they dramatically increased to 1176 g and 1713 g when BM mixed with BMC was used.
The aerobic treatment yielding Aerobically treated Biomass (ABM), and the combination with BMC, significantly enhanced okra yields, doubling and tripling production compared to the control. BMC demonstrated the highest nutrient content across all experiments, with a notable C/N ratio, total nitrogen, and total phosphate levels. Heavy metal analysis confirmed that the concentrations of arsenic, cadmium, and mercury in BMC-treated soil were within permissible limits. The results suggest that BMC is a potent sustainable fertilizer, improving okra yield and ensuring soil safety. This study confirms the positive impact of biosolids obtained from stabilized fecal sludge on agricultural productivity, particularly for okra crops.