the effect of organic, biological and chemical fertilizers on yield, essential oil percentage and some agroecological characteristics of summer savory (satureja hortensis l.) under mashhad conditions

introduction savory (satureja hortensis l.) is an annual herbaceous plant that belongs to the lamiaceae family. nowadays, the use of biofertilizers is increased in agriculture and their role in increasing the crops production has been demonstrated in many research works (vessey, 2003; chen, 2006; mahfouz & sharaf- eldin, 2007). one of the most important visions is sustainable production of enough food plus paying attention to social, economical and environmental aspects. (gliessman, 1998) stated that the first step to achieve this goal is optimization and improvement of resources use efficiencies. considering medicinal importance of savory and its role in the food and pharmaceutical industries (omidbeigi, 2000), beside the limited nutrient resources and need to increase healthy production through using ecological inputs, this study was designed and conducted aimed to evaluate agroecological characteristics of savory as affected by the application of bio fertilizers, chemical and organic fertilizers under mashhad conditions. materials and methods in order to study the effects of organic, biological and chemical fertilizers on quantitative and qualitative characteristics of summer savory, a split-plot design based on rcbd with three replications was conducted during the growing season of 2012 at the agricultural research station, college of agriculture, ferdowsi university of mashhad, iran. different levels of cattle manure (0 and 25 t.ha-1) were assigned to the main plots and different types of bio fertilizers (nitroxin, containing azotobacter sp. and azospirillum sp., biophosphor, containing phosphate-solubilizing bacteria (bacillus sp. and pseudomonas sp.), biosulfur, containing sulfur-solubilizing bacteria (thiobacillus ssp.), combination of nitroxin+biophosphor+ biosulfur), vermicompost (7 t.ha-1), chemical fertilizers (npk: 60, 60 and 70 kg.ha-1) and control (no fertilizer) were used in the sub- plots. results and discussion according to the results, all studied characteristics including plant height, lateral branches, flowering shoot yield, stem yield, percentage of essential oil and dry matter yield were affected positively by cattle manure. the highest plant height and number of lateral branches resulted from vermicompost and combination of nitroxin+biophosphor+biosulfur, respectively. biosulfur fertilizer produced the highest dry matter yield, flowering shoot yield and stem yield. percentage of essential oil was also significantly affected by fertilizer treatments as the most percentage of essential oil was obtained from nitroxin, vermicompost and combination of nitroxin+biophosphor+biosulfur. a positive and strong correlation was observed between dry mater yield and flowering shoot yield and stem yield, respectively. conclusion the results indicated that application of organic and inoculation of biological fertilizers have positive effects on improvement of qualitative and quantitative traits of summer savory, so it could be considered as an alternative method for healthy production of summer savory. acknowledgements the expenses for this research were funded by the research and technology deputy of the ferdowsi university of mashhad, faculty of agriculture. the financial support is appreciated. references chen, j. 2006. the combined use of chemical and organic fertilizers and/or biofertilizer for crop growth and soil fertility. international workshop on sustained management of the soil-rhizosphere system for efficient crop production and fertilizer use. october 16-20. thailand. 11 pp. gliessman, s.r. 1998. agroecology: ecological processes in sustainable agriculture. crc press. isbn: 1-57504-043-3 mahfouz, s.a., sharaf- eldin, a. 2007. effect of mineral vs. biofertilizer on growth, yield, and essential oil content of fennel (foeniculum vulgare mill.). agrophysics journal 21: 361-366. omidbeigi, r. 2000. approaches to production and processing of medicinal plants, vol. (3). beh nashr publisher, mashhad. (in persian) vessey, j.k. 2003. plant growth promoting rhizobacteria as biofertilizers. plant and soil 255: 571-586.