Avalia？？o de germoplasma de camomila e densidade de semeadura na produ？？o e composi？？o do óleo essencial

the cultivar mandirituba is the only genetic material for chamomile cultivation in southern brazil. besides the limitations regarding floral buds and the yield of essential oil presented by this cultivar, phytosanitary problems have also been observed. the objectives of this work were to compare the genetic materials from the netherlands, denmark and mandirituba and to evaluate the effect of seeding rate on floral heads development and essential oil production, yield and quality. the experiments were carried out at field conditions in piraquara, paraná state, brazil. the essential oil extraction was obtained by hydrodistillation using a clevenger apparatus and the oil composition was analyzed by gas chromatography coupled to mass spectrometry (gc/ms). the genetic materials from the netherlands and mandirituba presented statistically higher dry mass accumulation than the ones from denmark. however the material from mandirituba showed a great essential oil yield (4.7 ml g-1 ms) and productivity (2.40 l ha-1). the genetic material from denmark and mandirituba showed similar essential oil composition. the density of 1.0 kg ha-1 for cultivar mandirituba resulted on great plant development and essential oil production. the use of 3.0 kg ha-1 of seeds did not increase plant density due to the high plant competition.