Estimation of productivity yield gap contributions of climate change variability in selected horticultural crops (fresh maize and okra) in Anambra State, Nigeria

Most horticultural crops are susceptible to climate extremes that affect vegetative growth and yield. Climate variability poses a great threat to food security and the sustainability of the agricultural sector in Nigeria. However, the study estimated the productivity yield gap contributions of climate variability among maize and okra farmers. Data was collected from a cross-section of 160 farmers. Statistical tools such as descriptive statistics, second-order quadratic and linear regression models and Chi-square were utilized to operationalize the study objectives. The study established that high temperature was the highest climate variability (okra - 80.0%, and maize - 78.7%); whereas fug was lowest with 38.3% (okra) and 30.4% (maize). Again, flood contributed to the highest (27.5% - okra, and 36.5% - maize) yield gap. All the climate variability cumulatively explained 6.49 ton/ha (maize) and 3.47 ton/ha (okra) yield gap. However, the farmers are producing 2.26 ton/ha (maize) and 1.70 ton/ha (okra) below their optimal level. For better management, the study revealed that sex, age, education, household size, and cooperative membership are responsible for okra farmers; while age, marital status, and farming experience are responsible for maize farmers’ managerial ability. The study, therefore, concludes that climate variability significantly reduced horticultural crop yield. Howbeit, the study recommends that farmers should be taught to adopt climate-smart agricultural practices.