Increased Production of Hybrid Corn (Zea mays L.) in Sinaloa, Mexico through the Application of Sewage Sludge and Traditional Fertilizer

Abstract

Background: Sewage sludge (SS) contains organic matter and plant-available nutrients that may contribute to soil fertility and reduce reliance on inorganic fertilisers. However, its agricultural use requires careful evaluation because of potential microbiological and chemical risks. Aim: This study evaluated whether partial substitution of conventional fertiliser with SS could improve hybrid corn (Zea mays L.) production and replenish selected soil nutrients under field conditions in Sinaloa, Mexico. Method: Six 6 × 8 m plots were established with SS/fertiliser proportions of 0/100, 5/95, 10/90, 15/85, 20/80, and 25/75. The experiment was conducted from October 2025 to March 2026. Soil pH, organic carbon, and available nitrogen, phosphorus, and potassium were measured at the beginning and end of the experiment. Crop responses included estimated yield, plant height, number of grains per cob, and fresh cob weight. Results: The 20/80 and 25/75 SS/fertiliser treatments produced higher agronomic values than the fertiliser-only control. Estimated yields reached 10.2 and 10.4 tonnes/ha, respectively, compared with 9.2 tonnes/ha in the control. The 25% SS treatment also reached 253 cm plant height, 528 grains per cob, and 270 g fresh cob weight. The higher-SS treatments also showed favourable changes in measured soil nutrient variables. Conclusion: Moderate substitution of inorganic fertiliser with SS may support hybrid corn productivity and nutrient recycling under the conditions evaluated. Nevertheless, its agricultural use should remain cautious because sewage sludge may contain pathogenic microorganisms and potentially harmful contaminants.