تاثير نحوه مصرف ريزمغذي ها و تراكم بوته بر عملكرد و اسانس نعناع فلفلي (Menta piperita L)

The effects of application microelements and plant density on yield and essential oil of peppermint (Mentha piperita L.)

Peppermint (.Mentha piperita L.) from Lamiaceae family is one of the most important mcdicinal plants, used in food, sanitary and cosmetic industries. A field experiment was carried out in Tabriz University in 2005. In this study, the effects of four plant densities (8, 12, 16 and 20 plants/m2) and microelements of two level (nonspraying, spraying) on yield and essential oil production of peppermint were evaluated at two cuttings. The data obtained from each harvests by factorial experiment on the basis of randomized complete block design (RCBD) with three replications and two cutting analysis of compound variance (split plot on time). The results of the first cutting showed that microelements of spraying dry yield, bush and leaf essential oil percentage and essential oil yield increased. In the first cutting dry yield, the oil yield increased by increasing the plant density. In second cutting, microelement spraying cause dry yield and leaf essential oil percentage and essential oil yield of significant affected. Also dry yield increased by increasing the plant density. The results of two cutting indicated that peppermint plants grown better in the first cutting than the second cutting. Plants harvested in first cutting had higher dry yield and essential oil yield, but had lower bush and leaf essential oil. The maximum leaf essential oil percentage (2.96%) obtained with spraying in the second cutting. The maximum essential oil yield was obtained (20.02 li.ha"1) in the first cutting.