Inhibition of ethylene response by 1-methylcyclopropene in potted ornamental pepper

Abstract

In the face of great potential of 1-MCP in blocking ethylene action, this study aimed to evaluate the efficacy of 1-MCP on ethylene action and extend the post-production of ornamental peppers Capsicum annuum potted plants. Ornamental pepper cultivar Calypso shows complete abscission of leaves when exposed to 10µL L-1 ethylene. By exposing plants to ethylene, significant drops on a, b and total chlorophyll were found at the end of the treatment. Nevertheless, no changes on leaf total carotenoid were observed after the treatment with ethylene. When the plants were treated with 1-methylcyclopropene (1-MCP), followed or not by treatment with ethylene, contents of a, b, total chlorophyll and carotenoid remained unchanged. Control plants showed no changes in chlorophylls or carotenoid contents after 48 hours from moving the pots from greenhouse to indoor conditions illuminated with white fluorescent light. The 1-MCP was able to prolong the post production shelf life, by inhibiting the abscission of leaves. Plants treated with 1-MCP, followed by ethylene had 38% accumulated leaf abscission, after 18 days of post production life, similar to control plants. After the same period, plants treated only with 1-MCP had 22% leaf abscission. The 1-MCP partially blocked ethylene and induced leaf abscission. Regardless which treatment was applied during post production life, there was a continuous decrease on leaf chlorophyll content beyond 18th day. Thus, 1-MCP was effective in preventing leaf abscission even in the presence of ethylene, avoiding deleterious effects of ethylene by blocking its receptor sites.