Abstract :
Apple production is largely affected by the fungi Colletotrichum
gloeosporioides and C. acutatum, causal agents of fruit bitter rot. Economic
losses account for 30-80%. Colletotrichum spp. are the most destructive if the
infection occurs after harvest and storage. The disease is managed by fungicide
application during the season. Due to increased concern for human health and the
environment, as well as to problems with pathogen resistance development, ecofriendly
alternatives to chemical control measures, such as essential oils, became
the object of many researches. The aim of the study was to investigate which
essential oils have a potential to be used as control agents against Colletotrichum
spp. Effects of volatile phase of 56 essential oils on C. gloeosporioides and C.
acutatum were investigated. For both fungal species, oregano oils A, B, C and D
were fungicidal at rates ranging from 0.02 to 0.04 ?l/ml of air, and oregano oil E
at rate of 0.08 ?l/ml of air. Minimum inhibitory concentration for thyme oil
ranged from 0.02 to 0.04 ?l/ml of air. Out of 56 tested essential oils, 47 oils did
not stop mycelial growth even at concentration of 0.16 ?l/ml of air. The results
indicate that oregano and thyme essential oils have a potential in management of
investigated apple pathogens.
