Fumigation and dip treatments with 1H-cyclopropabenzene and 1H-cyclopropa[b]naphthalene suppress ethylene production and maintain fruit quality of cold-stored ‘Cripps Pink’ apple

Abstract

The effects of dip and fumigation treatments with two novel ethylene antagonists namely 1H-cyclopropabenzene (BC) and 1H-cyclopropa[b]naphthalene (NC) as well as 1-methylcyclopropene (1-MCP), in reducing the ethylene production and respiration rates and maintaining fruit quality of cold-stored ‘Cripps Pink’ apple were investigated. The apple fruit were fumigated with 1 μM BC, 1 μM NC, or 18 μM 1-MCP for 18 h. For dip treatment the fruits were dipped in 20 L aqueous solution containing 5 % ethanol only, 2 μM BC in 5 % ethanol or 2μM NC in 5 % ethanol for 5 min (at 20 ± 2 °C). The untreated fruit were considered as control. Following 100 d and 150 d of cold storage, in sequence the fumigation treatment with 1-MCP, the fumigation and dip treatments with BC and NC were effective in retarding the ethylene production, reducing physiological loss of weight (PLW) as well as in maintaining higher firmness, total phenol levels and titratable acidity in the fruit, when compared to control and ethanol treatments. The BC and NC fumigation treatments performed better than respective dip treatments in retarding ethylene production and maintaining the quality of ‘Cripps Pink’ apple fruit.