تاثير مقادير و روشهاي مصرف نيتروژن برتعدادي از ويژگيهاي كمي و كيفي گياه دارويي مرزه

The effects of different methods and levels of using nitrogen on some quality and quantity characteristics of Satureja hortensis L.

The effect of applying different methods and nitrogen levels on yield and essential oil of savagery (Satureja hortensis L.) was investigated using a factorial experiment based on randomized complete block design with 3 replications in 2005, Karaj, Iran. The treatments included application of solid nitrogen in soil with 4 levels 0, 50, 100 and 150 kg/ha and spray of nitrogen on foliage with 4 levels 0, 4.5, 6 and 7.5 percent. The nitrogen applied three times equally. The results showed, effect of treatments on biological yield, plant height, essential oil percentage, flowering shoot yield, number of lateral branch (P< 0.01) and harvest index were significant (P<0.05). Interaction of treatments on essential oil percentage, essential oil yield, flowering shoot yield (P<0.01) and biological yield (PO.05) were significant. This experiment found that applying 100 kg pure nitrogen in soil with 4.5% produced highest biological yield, seed and flowering shoot with means of 4424, 875.3 and 1855 kg ha"1, respectively. The results showed, increase of nitrogen application caused decrease of essential oil percentage. Highest essential oil percentage related to application of 6% of nitrogen solution with mean of 2.13%. Utilization of 150 kg of solid nitrogen with 7.5% of nitrogen solution produced highest plant height with mean of 66.88 cm, highest lateral branch with mean of 18 and highest essential oil yield with mean of 33.7 kg ha"1. Highest harvest index related to control with mean of 25.98%. The results showed that use of sprayed nitrogen on foliage decrease nitrogen application. Therefore, this method could be suitable for sustainable agriculture.