Yellowing of broccoli in storage is reduced by 1-methylcyclopropene

Broccoli (Brassica oleracea L. var. italica Plen) was held for 12 days at 10 degrees C in air or in ethylene (1 mu L.L-1), with or without prior exposure to MCP (1 mu L.L-1) for 12 hours. In a second experiment, the effects of concentration of MCP, prior to exposure to ethylene, were evaluated. Treatment with MCP reduced whereas exposure to ethylene stimulated respiration and yellowing. Treatment with MCP before continuous exposure to ethylene negated the effects of ethylene. The inhibitory effect of MCP on respiration of broccoli exposed to I mu L.L-1 ethylene was concentration-dependent, while the effect on yellowing was not. The results indicate that the yellowing of broccoli is mediated by ethylene action, and that MCP treatment inhibits yellowing and reduces respiration, even when broccoli is exposed to ethylene. Chemical name used: 1-methylcyclopropene (MCP).