Socio-Ecological Systems Theory Applied to Understanding Adoption Barriers for Disease-Resistant Cassava Varieties in Northern Nigeria

The low adoption rate of disease-resistant cassava varieties released by IITA and NRCRI across Northern Nigeria represents a persistent gap between plant pathology research output and measurable on-farm disease management impact. Despite high-yielding CMD and CBSD-resistant varieties being available for more than a decade, adoption remains below 30 percent in most North Central and North West cassava-growing communities. This doctoral research applies socio-ecological systems theory as an original theoretical framework for diagnosing adoption barriers, treating the cassava seed system as a complex adaptive system in which social, ecological, institutional, and technological components interact to produce observed adoption trajectories. Empirical data are collected from 450 farming households and 60 key informants across Kogi, Benue, Niger, Kaduna, and Kano States using a mixed-methods design incorporating structured surveys, focus group discussions, participatory system mapping, and agent-based model simulation. Qualitative comparative analysis is used to identify configurations of enabling and constraining conditions associated with high versus low adoption outcomes. Original contributions include the first application of socio-ecological systems theory to cassava variety adoption in West Africa, a generative agent-based model of variety dissemination under different institutional scenarios, and a novel composite adoption readiness index validated across the surveyed communities. Policy recommendations target specific institutional leverage points within the cassava seed system, including informal seed network formalisation, community demonstration plot programmes, and gender-targeted incentive structures. Keywords: socio-ecological systems, cassava, variety adoption, Northern Nigeria, seed systems.