* Present address: Assistant Horticulturist PAU Regional Research Station Gurdaspur, Punjab-143521
Ethylene inhibitors such as n-propylgallate, silver nitrate and benzothiadiazole at different concentrations were sprayed on Red Delicious apple tree at 10 and 15 weeks after full bloom. The fruits were harvested at maturity. Silver nitrate and benzothia-diazole at 100 mgl−1 concentration were found to be most effective in slowing down the polygalacturonase, cellulase and malic dehydrogenase enzyme activities of the fruit after harvest and during storage at 0±1°C temperature and 90–95 per cent relative humidity. These prolonged the shelf life of the fruits.
