DETERMINANTS OF TECHNICAL EFFICIENCY OF SWEET POTATO FARMERS IN IMO STATE, NIGERIA
Authors: OSUAGWU, Chizoma Olivia; ESIOBU, Nnaemeka Success; OHAEMESI, Chidubem Francis; CHIBUNDU, Emeka Ikechi; ANYANWU, Rosita Chinwe; NWACHUKWU, Emmanuel; ONYEOMA Uruchukwu Mary; AGUNANNE, Uchenna Theresa and Oparaojiaku, Joy Obiageli
OSUAGWU, Chizoma Olivia: Department of Agricultural Economics, Faculty of Agriculture, University of Agriculture and Environmental Sciences (UAES), Umuagwo, Imo State, Nigeria.
ESIOBU, Nnaemeka Success: Department of Agricultural Economics, Faculty of Agriculture, University of Agriculture and Environmental Sciences (UAES), Umuagwo, Imo State, Nigeria.
OHAEMESI, Chidubem Francis: Department of Agricultural Economics, Faculty of Agriculture, University of Agriculture and Environmental Sciences (UAES), Umuagwo, Imo State, Nigeria.
CHIBUNDU, Emeka Ikechi: Department of Agricultural Economics, Faculty of Agriculture, University of Agriculture and Environmental Sciences (UAES), Umuagwo, Imo State, Nigeria.
ANYANWU, Rosita Chinwe: Department of General Studies, University of Agriculture and Environmental Sciences (UAES), Umuagwo, Imo State, Nigeria.
NWACHUKWU, Emmanuel: Department of General Studies, University of Agriculture and Environmental Sciences (UAES), Umuagwo, Imo State, Nigeria.
ONYEOMA Uruchukwu Mary: Department of Agricultural Economics, Faculty of Agriculture, University of Agriculture and Environmental Sciences (UAES), Umuagwo, Imo State, Nigeria.
AGUNANNE, Uchenna Theresa: Department of Agricultural Management, Imo State Polytechnic Omuma, Imo State, Nigeria.
Oparaojiaku, Joy Obiageli: Department of Agricultural Extension, University of Agriculture and Environmental Sciences (UAES) Umuagwo, Imo State, Nigeria.
ABSTRACT
Sweet potato (Ipomoea batatas L.) is a one of the vital food and nutrition security crop in sub-Saharan Africa, with Nigeria ranking as the second-largest global producer. Despite its importance, empirical evidence on the technical efficiency of sweet potato farmers in Imo State remains limited. This study analyzed technical efficiency using primary data from 126 farmers during the 2024/2025 cropping season. A multistage sampling technique was adopted, while structured questionnaire was used for data collection. The Cobb-Douglas stochastic frontier production function and Battese and Coelli model were employed for estimation. Descriptive results show a mean farm size of 0.47 ha, average age of 43 years, 8.16 years of education, and 11.06 years of farming experience. Mean output was 149.37 kg, fertilizer use 394.56 kg, labour input 30.12 man hour, and extension contact averaged 0.85 visits per year. The stochastic frontier results revealed that farm size (0.082), planting materials (0.259), agrochemicals (0.066), labour (0.197), fertilizer (0.088), and capital (0.643) significantly increased output at the 1% level. The gamma value (0.723) indicates that 72.3% of output variation is due to inefficiency, while lambda (1.615) confirms its dominance. Mean technical efficiency was 0.60 (range: 0.15-0.96), implying that farmers achieve only 60% of potential output. Efficiency was positively influenced by education (0.049), farming experience (0.085), farm size (0.063), extension contact (0.074), improved planting materials (0.088), credit access (0.082), and cooperative membership (0.056). Major constraints include high input costs (3.68), poor extension access (3.55), climate variability (3.47), limited credit (3.42), and pest infestation (3.36). The findings indicate substantial inefficiency and the need for targeted policy interventions.
Keywords: Sweet potato; Technical Efficiency; Stochastic Frontier Production Function; Constraints; Imo State, Nigeria.