Résumé
The effect of thyme oil (96 μL L−1) vapours on the expression of phenylalanine ammonia-lyase (PAL) and lipoxygenase(LOX) genes, and control of anthracnose was investigated in naturally infected ‘Hass’ and ‘Ryan’avocado fruit stored for 21 d at 7–7.5 °C, and thereafter kept for 5 d at 20 °C, simulating the supply chainconditions. Exposure to thyme oil vapours prior to cold storage resulted in up-regulation of the PAL gene expressionin both ‘Hass’ and ‘Ryan’ avocado when compared with untreated fruit and those treated with prochloraz®. The higher expression of PAL gene was observed in ‘Ryan’. Thyme oil vapours exposure resulted in thehigher epicatechin content. At the same time, exposure to thyme oil vapours led to down-regulation of LOX geneexpression in both cultivars. Thus, simultaneous up-regulation of PAL gene and down-regulation of LOX gene inavocados exposed to thyme oil vapours prior to cold storage was associated with higher epicatechin content inthe fruit. Therefore, it can be concluded that postharvest application of thyme oil vapours increases anthracnosedisease resistance in ‘Hass’ and ‘Ryan’ avocado fruit.