According to the study of Soylu in the topic “ In vitro and in vivo antifungal activities of the essential oils of various plants against tomato grey mould disease agent Botrytis cinerea”
to determine The effects of different concentrations of volatile (A) and contact (B) phase of essential oil the controls received ethanol and tween20 mixed with PDA and b.cinerea was inoculated immediately by plating in the center of each plate the Petri dishes were incubated in the dark at 22 °C.
as for determination of effects of each phase three types of essential oil which is origanum lavender and rosemary and two tests were used for each phase.
for volatile phase petri dishes , which inoculated at different concentrations of essential oil were added to sterile filter paper and petri dishes to obtain final concentration of 0.05 to 1.6 mm/ml air the petri dishes were sealed immediately with parafilm to prevent loss of essential oil vapours and incubated at 22องศา earlier process resulted in antifungai effect , which vary directly with essential oil concentration and completely stunt the growth of Botrytis cinerea at 1.6 mm/ml as for effect determination of contact phase the essential oil were dispersed as an emulsion in water using ethanol and tween20 and added to PDA immediately before it was emptied into the glass petri dishes at temperature of 40-45องศา
the process completely stopped the growth of b.cinerea at 25.8 mm/ml and the effect vary directly to concentration of essential oils.
in conclusion effects of volatile phase greatly beater contact phase