The rise and fall of onion production; its multiple constraints on pre-harvest and post-harvest management issues along the supply chain in northwest Ethiopia

**Background:** Onion is an important cash crop in Ethiopia, but its production and productivity remain low due to various constraints. Postharvest losses exacerbate food insecurity and reduce farmer income. This study aimed to identify multiple constraints on onion production and postharvest handling practices and to determine the extent of postharvest loss along the supply chain in northwestern Ethiopia.

**Methods:** A cross-sectional survey was conducted from August 2021 to March 2022 in three potential onion-producing districts (Mecha, Fogera, and Bahir Dar Zuria) of northwestern Amhara, Ethiopia. A multistage sampling procedure was used to select 197 onion farmers, 15 wholesalers, 50 retailers, and 50 consumers. Primary data were collected through face-to-face interviews using a structured questionnaire, key informant interviews, direct field observation, and market assessment. Data were analyzed using SPSS version 16.0. Descriptive statistics, chi-square tests, ANOVA, and independent sample t-tests were employed to explore associations between socio-demographic factors and onion production/postharvest loss.

**Key Results:** The majority of onion producers were male (98.5%), while retailers were predominantly female (75.8%). The average age of producers was 44.7 years, and the average household size was 5.7. Chi-square analysis showed that sex (X²=89.125, p=0.009), age (X²=2957.97, p=0.000), educational level (X²=406.61, p=0.04), household size (X²=622.6, p=0.000), production experience (X²=1212.57, p=0.000), and land covered by onion (X²=894.4, p=0.000) had significant influence on onion production. For postharvest loss, sex, age, education level, active household size, selling experience, amount purchased, and storage duration were significantly associated at producer and consumer levels. At the retailer level, selling experience and storage duration were significant. Major production constraints included high postharvest loss, market linkage problems, low market price, lack of awareness of postharvest technologies, absence of better storable varieties, shortage of fertilizer access, and disease/insect pests. The average yield was 16 tons/ha, below the world average of 19.7 tons/ha. The total postharvest loss along the supply chain was 29.775%, with the highest proportion at the farmer level (35.5%), followed by retail (27.77%), wholesale (19.81%), and consumer (16.87%). At the farm level, 10.58% loss was recorded; at wholesale, 5.9%; at retail, 8.27%; and at consumer, 5.025%. Only 13.2% of farmers grew hybrid onion varieties, and 82.7% had no information about hybrid seed accessibility. Fertilizer access was inadequate for 97.5% of farmers, and 98% applied fertilizer above the recommended rate. All farmers (100%) reported market problems, and 82.2% did not store onions for late selling. Brokers were involved in 100% of transactions, often manipulating prices.

**Clinical Implications:** Although this is not a clinical study, the findings have implications for food and nutrition security. Reducing postharvest losses of onion can improve household income and nutritional status. The study recommends training producers and handlers on affordable postharvest technologies, improving infrastructure and input access, and making marketing cooperatives functional to absorb surplus production and ensure continuous supply. Policy interventions should focus on sustainable production, handling practices, and supply of onion.