EFFECTS OF AROMATIC PLANTS ON POTATO STORAGE - SPROUT SUPPRESSION ANDANTIMICROBIAL ACTIVITY

Sprout suppressant properties of the essential oils of Lavandula angus tifolia (lavender), Mentha pulegium (mint), Mentha spicata (spearmint) , Origanum onites (Turkish oregano), Origanum vulgare ssp. hirtum (Gre ek oregano), Rosmarinus officinalis (rosemary), and Salvia fruticosa ( sage) were assessed. Except for oregano oils, all other essential oils suppressed potato sprout growth. Those of L. angustifolia, Salvia fru ticosa and R. officinalis were the most effective. Application of crud e herbs, instead of extracted essential oils, lead to comparable resul ts. The inhibition is reversible, thus allowing subsequent normal spro uting of seed potatoes. The essential oils of the above mentioned arom atic plants, as well as those of Coridothymus capitatus (Spanish orega no), Origanum dictamnus (Cretan dittany), and Satureja thymbra, were a lso found to possess potent antimicrobial activities against Erwinia c arotovora strains and bacteria isolated from the surface of potato tub ers. The carvacrol-containing essential oils, and particularly that of Greek oregano, had the strongest effect. Use of aromatic plants could be an effective and safe way to prolong the storage life of potato tu bers, at the same time protecting them from certain microbial attacks. This holds, in particular, for regions such as the Mediterranean, whe re prolongation of tuber dormancy needs more drastic and costly measur es, because of the high temperatures. As aromatic plants grow natively and in abundance, their use would be cost-effective.