Abstract:
Thyme oil (TO) fumigation (96 ll l 1) to cv. Hass and Ryan avocados significantly reduced anthracnose
incidence compared to prochloraz and the untreated control. Also, enhanced activities of b-1,3-
glucanase, chitinase were noted in both cultivars. TO fumigation induced the expression of both b-1,3-
glucanase and chitinase genes in naturally infected fruit of both cultivars, during storage at 7 or 7.5 C
for up to 21 d and during subsequent simulated market shelf conditions at 20 C for 5 d. However, the
impact of TO fumigation on the b-1,3-glucanase gene expression was higher in both cultivars. Higher
gene regulation and b-1,3-glucanase, chitinase activities were observed in cv. Ryan compared to Hass.
Although TO fumigation significantly reduced anthracnose incidence in both naturally infected cultivars,
the inhibitory effect was slightly higher in cv. Ryan than Hass. Thus, postharvest TO fumigation had positive
effects on enhancing anthracnose disease resistance during storage and also gave a residual effect
during the simulated shelf life.
