Characterization of Industrial Dairy Wastewater and Contribution to Reuse in Cereals Culture: Study of Phytotoxic Effect

The present work aims to study the impact of dairy effluents on seed germination and seedling growth of Wheat (Triticumaestivum) and Maize (Zea mays). Dairy effluents were collected from the inlet and outlet of waste water treatment plant of two dairy industries located in Tunisia in the areas of Sousse and Mahdia. Different physical and chemical parameters were evaluated for the assessment of effluents quality before and after treatment. Total suspended solids, BOD5, COD, detergents and Oils and fats of both Mahdia and Sousse dairy effluents decreased after treatment and were within permissible limits. While in the case of total Kjeldahl Nitrogen and total phosphorus, the reduction remained above limits. The use of treated effluent from both dairy plants enhanced seed germination and seedling growth of wheat. However, results showed inhibitory effect from the same effluents on maize seed germination and growth of roots and shoots. Observation showed that untreated effluent from Sousse dairy plant had inhibited seed germination for both wheat and maize but induced seedling growth.