Development of a thyme essential oil formulation and its effect on Monilinia ructigena

Abstract

Antifungal activity of thyme essential oil against Monilinia fructigena and development of an effective and stable oil formulation for agricultural use were studied in this paper. Bioactivity of the oil itself and its developed formulation, an emulsifiable concentrate (EC), was tested in vitro and in vivo. In vitro experiments, using a slightly modified agar overlay technique, showed that the initially emulsified thyme essential oil, as well as the developed formulation, significantly inhibited mycelial growth of M. fructigena in vitro. Experiments in vivo, performed on inoculated apple fruits, revealed that the formulation successfully decreased oil evaporation from the treated area and provided a significant level of M. fructigena suppression, 64.7-72.1% compared to the control. To our knowledge, an EC formulation of thyme essential oil for agricultural uses had never been developed before. The presented results are initial findings and evaluation of product activity should be continued in the field to determine its efficacy and activity spectrum, and to estimate the economic aspect of its use.

U radu je proučavana antifungalna aktivnost etarskog ulja timijana na Monilinia fructigena, kao i mogućnost razvoja efikasne i stabilne formulacije ulja za upotrebu u poljoprivredi. Bioaktivnost etarskog ulja kao i razvijene formulacije - koncentrata za emulziju (EC) testirana je u ogledima in vitro i in vivo. Ogledi in vitro, izvedeni po delimično modifikovanoj metodi testiranja antimikrobne aktivnosti na površini agara, pokazali su da i inicijalno emulgovano ulje i razvijena formulacija značajno inhibiraju porast micelije izolata M. fructigena. U ogledima in vivo na inokulisanim plodovima jabuke pokazano je da je procesom formulisanja značajno smanjena isparljivost ulja sa tretirane površine i postignuta inhibicija razvoja mrke truleži ploda 64,7-72,1% u poređenju sa kontrolom. Koliko nam je poznato, u ovom radu je po prvi put razvijena EC formulacija etarskog ulja timijana za upotrebu u poljoprivredi. Dobijeni rezultati predstavljaju početak istraživanja koje treba dopuniti rezultatima ispitivanja efekata razvijene formulacije u uslovima praktične primene, proučavanja spektra njenog delovanja, kao i ekonomske isplativosti njene primene.