Maximizing agricultural sustainability: determining the optimal biosolid dose for germination and initial growth of maize and cowpea

Abstract

Waste generated from industrial activities is often disposed of, but reusing these materials can reduce environmental impact and add value to the products. This research aims to identify the ideal dose of biosolid resulting from the lactic acid production, for use as organic fertilizer in germinating of cowpea (Vigna unguiculata) and maize (Zea mays). The experiment involved twelve treatments: commercial substrate, 100% sand, and proportions of the biosolid (2.5, 5.0, 7.5, 10.0, 12.5, 15.0, 17.5, 20,0, 22.5 and, 25.0%). Daily assessments of temperature and pH were carried out, and after ten days, morphological evaluations were performed. These evaluations included germination percentage, normal and abnormal seedlings, and the emergency speed index. Results indicated that maize showed more resilient germination at higher doses of biosolid residue, with fewer abnormalities compared to cowpea. Doses exceeding 5% of biosolid had adverse effects on both germination and seedling growth. For cowpea, a 2.5% residue dose did not significantly hinder seedling germination and growth. However, for maize, while the 2.5% residue did not affect the germination percentage, it did decrease the emergency speed and root length.