Study of Different Levels of Nitrogen, Phosphorus and Potassium on Physiological and Morphological Parameters and Essential Oils in Savory Plant (Satureja hortensis L.)

In present study, effects of foliar of NPK fertilizer on some physiological, morphological parameters and essential oil of medicinal plant of savory (Satureja hortensis L.) were studied. Experimental design was Randomized Complete Block design (RCB) with 4 treatment and 3 replications. Treatments were including control and foliar of NPK fertilizer with proportions of 20-20-20, 10-50-10 and 12-12-36. Highest number of leaves, lateral branches, height and wet and dry weight of roots and shoots was obtained by fertilizer treatment with ratio of 12-12-36. It seems that eminent role of potassium rather than nitrogen and phosphorus in fertilizer composition of 12-12-36 could lead to significant increases in these traits. The highest content of chlorophyll a with 0.161 mg g-1 F.W and the highest rate of carotenoid with 0.571 mg g-1 F.W were captured in fertilizer with ratio of 20-20-20. Control treatment revealed the most content of anthocyanin with 37.682 mg g-1 F.W. Low levels of anthocyanin in foliar application treatments in comparison with control sample may be because of creation the optimum condition for plants by application of fertilizer. Total essential oil content demonstrated fluctuations in different treatments so in plants with fertilizer treatments with ratio of 12-12-36 had the most essential oil productions rather than control and other fertilizer treatments. Outcomes of regression analysis by stepwise method showed that chlorophyll a, number of leaf and height had the most effect on dry weight of stem and could justify 85% of dry weight of stem.