1-MCP is more effective on a floral brassica (Brassica oleracea var. italica L.) than a leafy brassica (Brassica rapa var. chinensis)

Abstract

Florets of broccoli (Brassica oleracea var. italica L.) and the youngest fully expanded leaf detached from pak choy (Brassica rapa var. chinensis) were treated with 1-methylcyclopropene (1-MCP) overnight (16 h) and then stored at supermarket retail temperature (10 °C). A concentration of 12 μl l−1 was considered optimal for both pak choy leaves and broccoli florets. 1-MCP increased shelf life of broccoli florets by just greater than 20% but had little effect on pak choy shelf life (increases between 10 and 20%) in the absence of exogenously applied ethylene. Multiple applications had no further impact while 1-MCP needed to be applied as soon as possible after harvest to have maximal effect. If 1-MCP treatment was applied overnight at 20 °C prior to storage at 10 °C, its effect was slightly increased. However, 1-MCP did protect broccoli and pak choy from the effects of exogenously applied ethylene (0.1 or 1 μl l−1) suggesting it may be useful during retail or storage with ethylene-producing commodities. Differences between the efficacies of 1-MCP on florets compared with leaves are discussed.