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Ethylene induces postharvest problems in many fruits, including members of the Cucurbitaceae. The effects of ethylene and its antagonist 1-methylcyclopropene (1-MCP) were studied on cucumber fruit, a cucurbit harvested immature. Beit Alpha cucumbers (cv. Manar) were harvested and exposed to 0.5 or 1.0 μL·L-1 1-MCP prior to exposure to ethylene at 10 μL·L-1 at 15 °C. Fruit exposed to ethylene exhibited significant quality loss upon exposure to ethylene, including epidermal yellowing, a 40% reduction in firmness and, following longer exposure (6 d), epidermal sloughing and placental watersoaking. After 8 d, cucumbers exhibited a 75% reduction in firmness and acute pathogen incidence. Control fruit (no ethylene, no 1-MCP) were visually acceptable but firmness had declined 30% compared with initial values. Fruit exposed to 1-MCP were resistant to applied ethylene, with firmness declining 10 (1.0 μL·L-1 1-MCP) to 20% (0.5 μL·L-1) during storage for 14 d at 15 °C. Firmness of fruit treated with 1-MCP at 1.0 μL·L-1 was 28% higher than controls receiving only air, suggesting that ethylene production contributes to softening of cucumber during storage. The softening and watersoaking of fruit treated with ethylene was accompanied by downshifts in pectin mol mass. Fruit exposed to 1-MCP showed significantly reduced mol mass downshifts. The data indicate that cucumber show a PCD response to ethylene that is largely prevented by suppression of ethylene perception. The response of cucumber to ethylene parallels that for other cucurbits, and provides additional information that the benefits of 1-MCP extend beyond application to climacteric fruits.