Document Type : Research Paper
Authors
1 MSc. Graduate Student in Plant Breeding, Department of Agronomy and Plant Breeding Sciences, College of Aburaihan, University of Tehran, Pakdasht, Tehran, Iran
2 Department of Agronomy and Plant Breeding Sciences, College of Aburaihan, University of Tehran, Pakdasht, Tehran, Iran
3 Department of Pharmacognosy, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
Abstract
Study of phenological characteristics and determination of temperature requirement of medicinal plants leads to a better understanding of the extent and manner of growth and development. An accurate planning for optimal utilization of the plant and amount of active substances could be done based on this feature. This research was aimed to evaluate the phenological characteristics and classify early, late and medium maturity ecotypes of Ajowan (Trachyspermum ammi L.) as well as assessment of the essential oils extracted from each ecotype. In this study, 23 native ecotypes of Iranian ajowan were arranged in a randomized complete block design with three replications during 2014-2015. Growing degree-day (GDD) and the days after planting (DAP) were used to determine the exact date of phenological stages. Ecotypes were evaluated every three days and when 50% of the plants of each ecotype reached the phenological stage, the date was recorded. After ripening and harvest, essential oil was extracted by hydro-distillation method and clevenger apparatus. According to the results of this study, significant differences were found among ecotypes in terms of phenological traits. Flowering and granulation showed the most and least significant differences. The essential oil of samples varied between 2.7% (Sarbishe) and 6.1% (Arak). In addition, according to the results of mean comparison, four superior ecotypes in terms of early, medium and late maturity in each phenological stage were identified and classified. Physiological maturity and grain filling period were considered as a criterion to determine the early and late maturity. Accordingly, Arak (Markazi province) and Qaen (South Khorasan province) with an essence content of 6.1% and 4.7%, respectively were identified as the earliest and most late ecotypes.
Keywords
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