Influence of Integrated Nutrient Management on French Bean Productivity, Soil Properties, and Profitability under a Prunus salicina L. 'Mariposa'-Based Agroforestry System in the Kullu Valley

Abstract

Background: Integrated nutrient management may improve the productivity and resource-use efficiency of short-duration crops grown within fruit-tree-based agroforestry systems. This study evaluated French bean (Phaseolus vulgaris L.) under a mature plum (Prunus salicina L. 'Mariposa') orchard and in an open sole-cropping environment in the Kullu Valley, Himachal Pradesh. Methods: Twelve nutrient-management treatments were evaluated under two production systems in a factorial arrangement with three replications. The treatments included recommended mineral fertiliser, farmyard manure, vermicompost, goat manure, Jeevamrut, combinations of mineral and organic sources, and an unfertilised control. Crop growth, pod and biological yield, selected post-harvest soil properties, and farm-level economic returns were assessed. Results: Sole cropping produced greater pod length, pod width, number of pods, pod yield, and biological yield than the plum-based system, whereas the system difference in plant height did not exceed the reported critical difference. Across nutrient treatments, 50% recommended fertiliser plus 50% vermicompost (T7) produced the highest mean plant height, pod length, pod width, number of pods, pod yield, and biological yield. The plum-based system had lower post-harvest bulk and particle density and higher soil organic carbon and available nitrogen, phosphorus, and potassium than sole cropping. The agroforestry system also produced a higher mean net return (US$3,616.40 ha−1) and benefit-cost ratio (3.44) because plum income offset the reduction in understory bean yield. T7 produced the highest treatment-level mean net return, whereas 100% recommended fertiliser produced the highest treatment-level mean benefit-cost ratio. Conclusion: The results indicate a site-specific trade-off between maximum French bean yield in the open system and improved selected soil indicators and whole-system profitability under plum-based agroforestry. Combining mineral fertiliser with vermicompost was the most consistently productive nutrient strategy for French bean in this trial.