Stage-Contingent Information Efficacy: Disaggregating the Impact of Advisory Channels on Cocoa Management Practices in Southwest Nigeria

This study addresses the critical knowledge dissemination gap impeding sustainable cocoa production in Southwest Nigeria, where yields have declined by over 70% since the 1970s despite the availability of improved cultural management practices (ICMP). Using a mixed-methods approach (survey of 283 farmers, focused group discussion and Tobit regression), we investigated the stage-contingent efficacy of information sources on ICMP adoption across four production stages: nursery, on-farm, harvesting, and post-harvest. Results reveal farmer-led channels (Farmer Field Schools: 95.8%; Associations: 92.5%) dominate knowledge access, while institutional sources (CRIN, government agencies) are critically underutilised (< 5%). Adoption rates varied significantly by stage: nursery (38.3%), on-farm (73.8%), harvesting (77.4%), and post-harvest (88.1%). Tobit regression confirmed extension agents significantly increased nursery (β = 0.18, p < 0.01) and on-farm adoption (β = 0.05, p < 0.01), but paradoxically reduced harvesting adoption (β = −0.012, p < 0.10) due to contextual misfit (e.g., unaffordable tool recommendations). Tertiary education amplified adoption across stages (nursery: β = 0.30; post-harvest: β = 0.06), while institutional sources negatively impacted harvesting. Post-harvest practices relied solely on experiential learning (β = 0.001/year, p < 0.01), with no information-source effects. We propose a stage-targeted Agricultural Knowledge and Information System (AKIS) framework: farmer-led channels for nurseries, co-designed tools for harvesting, and digitised indigenous knowledge for post-harvest. Policy must prioritise context-adapted dissemination to reclaim Nigeria’s cocoa sector.