On-farm Evaluation and Economic Implication of Neem (Azadirachta indica) and Siam Weed (Chromolaena odorata) Leaves Powder in the Management of Plant-Parasitic Nematodes Associated with Yam (Dioscorea spp.)

Abstract

Plant-parasitic nematodes threaten yam production, causing yield losses and economic challenges. Eco-friendly management strategies are essential to reduce their impact while limiting synthetic nematicide use. This study was conducted in the late season of 2021 across two adopted villages of the Institute of Agricultural Research and Training: Ogbomoso (Oniyo) and Ibadan (Apete Onidoko) to evaluate the potentials of neem and siam weed leaves powder in the management of plant-parasitic nematodes in yam (Dioscorea spp.) field. Yam varieties were sourced from the adopted villages. Naturally infested farmers’ fields were selected for the experiment. Neem and siam weed slurry at 5 tonnes/ha were applied as fertilizers at the base of plants. At post planting soil samples were taken to determine nematode population. Data on vine length, tuber yield (kg/ha), nematode parameters were recorded. Data collected were subjected to Analysis of Variance using Statistical Tool for Agricultural Research (STAR) version 2013. Means were separated using Duncan Multiple Range Test (DMRT) at a 5% probability level. Neem and siam weed at 5 t/ha effectively managed plant-parasitic nematodes, significantly reducing Scutellonema bradys, Pratylenchus sp., and Meloidogyne sp., while enhancing yam tuber. Also, the market analysis revealed that yam treated with neem extract had more economic returns due to larger tuber sizes, weight, and number of tubers recorded at harvest. These findings highlight neem and Siam weed as sustainable and eco-friendly management method, contributing to improved yam productivity and offering a viable alternative management method to synthetic nematicides in yam production.