Abstract
Effectiveness of recycled organic wastes/compost enriched with nitrogen and/or L-tryptophan (L-TRP) was tested for improving the growth and yield of maize by conducting pot and field experiments. Fruit and vegetable wastes were collected from different locations and subjected to composting in a locally-fabricated unit. Composted product was enriched with 25% recommended rate of nitrogen and L-TRP @ 5 mg kg-1 compost. Recommended doses of chemical fertilizers (NPK) were kept for comparison. Results revealed that the application of compost enriched with Nand L-TRP in combination with 50% additional dose of N fertilizer significantly increased the plant height (up to 39%), fresh biomass (up to 53%), cob weight (up to 72%) and grain yield (up to 72%) of hybrid maize in both pot and field experiments compared to control (PK fertilizer only). Comparison of enriched compost and chemical fertilizers indicated that enriched compost supplemented with 50% N fertilizer was equally effective in improving the growth and yield of maize compared with chemical fertilizers (NPK), resulting in saving of - 25% of recommended N fertilizer. These findings may imply that organic wastes could be recycled into value added soil amendments for sustainable agriculture to reduce the pollution threat to environments. Key words: organic wastes, compost, soil amendments, crop production
