Phytotoxicity of methyl bromide fumigation to a range of apple cultivars

Abstract

Two trials were conducted to study the phytotoxicity of methyl bromide fumigation to a range of apple cultivars. Crofton was highly susceptible, being injured by all concentration x temperature combinations studied. Democrat was moderately susceptible, being injured by 32, 48 and 64 g m-3. The cultivars Red Delicious, Jonathan and Granny Smith had a relatively low susceptibility as they were injured only slightly by 32 g m-3 methyl bromide at 15¦C. The other cultivars, namely Legana and Golden Delicious, were not injured by any of the dosages. The amount of injury in Croftons and Democrats varied from orchard to orchard. Dosagehemperature combinations considered equivalent for efficacy purposes resulted in different levels of methyl bromide injury on these two cultivars. Spartan was the only cultivar in which any dosages of methyl bromide produced significantly more of the storage disorder internal breakdown than occurred in non-fumigated fruit.