Drivers of Postharvest Loss among Citrus Farmers in Eastern Cape Province of South Africa: A Zero-Inflated Poisson (ZIP) Regression Model Analysis

Abstract

Reducing postharvest losses (PHLs) in the South African citrus industry is fundamental in ensuring food, income, and nutrition security. However, there is limited knowledge on the extent of postharvest losses, their diversity, and the associated inhibiting factors. These factors compromise postharvest loss management strategies and how they can be scaled up across production zones in South Africa. The study adopted a pragmatic philosophy to assess the magnitude and diversity of PHLs for citrus crops and assess the determining factors. A standardized questionnaire was administered to 137 citrus producers from the Eastern Cape Province’s three production zones. Multistage sampling which combined purposive and stratified proportionate sampling was utilized to select the province, production zones, and farmers. The study employed the embedded research approach with a zero-inflated Poisson (ZIP) model. The countfit and Vuong tests were used in Stata 15 to ascertain and correct for overdispersion and inflated zeros while isolating the model which best fitted the data. The ZIP regression model indicated that social (e.g., marital status, education, age), economic (e.g., yield), institutional (e.g., markets, extension, credit), and cross-cutting (e.g., pruning, cultivar) factors determined the magnitude of PHL exposure. Targeted and tailored capacity building on good agricultural practices in citrus production might help to reduce postharvest losses through the extension pillar. The production of Nova and Navel citrus cultivars may be promoted when these cultivars are easily accessible and available to farmers while researching other traits to reduce PHL incidences. Investment programs to support the use of water-efficient drip irrigation systems need to be initiated to reduce the chances of incurring considerable postharvest losses. Likewise, pest and disease control in citrus production should be intensified and targeted. Subsidized support for the maintenance of citrus plantations should be provided by the government and other stakeholders, such as citrus production associations.