the effect of organic and biofertilizers on some quantitative characteristics and essential oil content of summer savory (satureja hortensis l.)

plant growth promoting bacteria with various mechanisms such as an increase in uptake and availability of nutrients can improve plant growth. in order to evaluate the effects of biofertilizers and vermicompost on quantitative characteristics and essential oil content of vegetative parts of summer savory, a field experiment was conducted during growing season of 2008- 2009 at agriculture research station, faculty of agriculture, ferdowsi university of mashhad, iran. a randomized complete block design with three replications was used. treatments included: nitragin, nitragin+vermicompost, nitragin+nitroxin, nitragin+phosphate solublizing bacteria, nitragin+phosphate solublizing bacteria+vermicompost, nitragin+phosphate solublizing bacteria+nitroxin, nitragin+nitroxin+vermicompost and control. plants were harvested twice at 10% flowering stag. the result showed that biofertilizers and vermicompost had significant effects (p≤0.01) on plant height, percentage of leaf and stem, biological yield and essential oil contents of leaves in both harvests. the combination of nitragin + nitroxin and vermicompost and control treatments had the highest and the lowest plant height, percentage of stem and leaf, and biological yield. it seems that seed inoculation with biofertilizers enhanced root development and hence availability of moisture and nutrients, particularly nitrogen and phosphorus. therefore, summer savory inoculation with biofertilizers could improve some quantitative and essential oil contents.