Condition of curry leaves exposed to quarantine treatments of cold, gamma irradiation, or methyl bromide fumigation

In separate treatments, leaves of the curry leaf tree [Murraya koenigii (L,) Sprengel] were subjected to 15 days at 1 degrees C, to gamma irradiation from a Co-60 source at dosages from 100 to 1000 Gy, or to fumigation with methyl bromide from 16 to 64 g.m(-3). Cold-treated leaves retained their fresh appearance with minimal weight loss when stored in sealed plastic bags; although color intensity of the underside of leaves was measurably reduced, the change was not visually perceptible, Similarly, irradiation was associated with a darkening of leaves and a loss of color intensity, but these changes were not visibly apparent even at the highest dosage. Methyl bromide fumigation, however, greatly increased susceptibility of leaves to postharvest decay. Cold or gamma irradiation treatments should be tolerated by this commodity when treated for pests such as the Asian citrus psgllid (Diaphorina citri Kuwayama) prior to export.