The effect of different levels of vermicompost and irrigation on morphological properties and essential oil content of German chamomile (Matricaria recutita) C.V. Goral

German chamomile (Matricaria recutita) is one of the most important essential oil bearing plants that its essential oil constituent (Chamazulene, Bisabolol and Bisabolol oxide A, B) is used in different medicinal industries. In this research, effect of different levels of vermicompost and irrigation was evaluated on morphological characteristics and essential oil content of “Goral” an improved German chamomile. The research was conducted in pot and greenhouse system. The treatments included four amounts of vermicompost (0, 5, 10 and 15% w/w) and three irrigation regimes (2 mm per week, 4mm per 2 weeks and 2 mm per 2 weeks). The studied factors were flower dry yield, plant height, flowering time, anthodia height, anthodia diameter, oil content (%) and essential oil yield. The results indicated that the vermicompost application improved plant height, early flowering, flowers dry weight, anthodia height and diameter significantly. Irrigation also affects plant height, flower dry weight and flowering time significantly and 2mm irrigation per two weeks was the best method and 2mm irrigation per week increased anthodia height and diameter significantly. The interactions between vermicompost and irrigation was significant as plant height (64.82 cm), flowers dry weight(7.84 gr per pot) and flowering time (35.5 days) as concerned and the best treatments was 15% vermicompost and irrigation 2mm per two weeks. The highest essential oil yield detected in 10% vermicompost and irrigation 4mm per two weeks (2.23 mg/pot). According to the results, it appears that 15% vermicompost plus 2 mm irrigation per two weeks was the best treatment to produce the flower yield in Goral cultivar of German chamomile in organic system.