Effects of Composts Derived from Neem ( Azadirachta indica ) Fruit Processing Residues on Tomato ( Solanum lycopersicum ) Growth and Yield under Greenhouse Conditions

Composting provides an effective solution for managing agro-industrial organic waste by reducing its environmental impact and producing fertilizers suitable for vegetable production. This study aimed to analyze the physicochemical properties of six composts produced from neem (Azadirachta indica) fruit processing residues (shells, pulp, and depulping sludge) composted alone or in co-composting with cattle dung and to evaluate their effects on the growth and yield of tomato (Solanum lycopersicum) under greenhouse conditions. An agronomic trial was conducted using a randomized complete block design with three replications and eight treatments, including a commercial municipal solid waste-based compost (T7) as a positive control. Physicochemical analysis revealed contrasting nutrient profiles among composts, with total nitrogen ranging from 0.35% (shells only) to 1.12% (sludge + cattle dung) and C/N ratios ranging from 21.2 to 35.3. Co-composting with cattle dung consistently improved nitrogen content and reduced C/N ratios across all substrate types. Agronomic results showed that the compost based on sludge and cattle dung (T4) yielded the best performance, with 18.33 ± 1.53 fruits per plant and an average fruit weight of 100.83 ± 1.60 g, significantly outperforming the commercial reference compost on fruit weight, despite comparable fruit counts. These findings demonstrate that composting neem fruit processing residues, particularly when co-composted with cattle dung, can produce quality organic amendments with significant agronomic potential for smallholder vegetable production systems.