ADDITIONAL INDEX WORDS. fruit quality, firmness, ethylene, Malus sylvestris var. domestica, postharvest physiology, storage
ABSTRACT. An ethylene action inhibitor, MCP, was applied to preclimacteric and climacteric apple [Malus sylvestris L.
(Mill.) var. domestica Borkh. Mansf.] fruit. Experiments were conducted in North Carolina and Washington State
utilizing the following cultivars: Fuji, Gala, Ginger Gold, Jonagold, and Delicious. MCP inhibited loss of fruit firmness
and titratable acidity when fruit were held in storage at 0 °C up to 6 months and when fruit were held at 20 to 24 °C for
up to 60 days. For all cultivars except ‘Fuji’, differences in firmness between treated and nontreated fruit exceeded 10
N after 6 months storage. These beneficial effects were seen in both preclimacteric and climacteric fruit. Ethylene
production and respiration were reduced substantially by MCP treatment. MCP-treated fruit had soluble solids equal
to or greater than those in nontreated fruit. Storage and shelf life were extended for all cultivars tested. Chemical name
used: 1-methylcyclopropene (MCP).