Influence of Planting Date on Growth, Yield, and Volatile Oil of Menthol Mint (M. arvensis) Under Marginal Land Conditions

Abstract

Mentha arvensis, commonly named menthol mint or Japanese mint, is an important volatile oil- bearing plant having high amounts of natural menthol. M. arvensis volatile oil (VO) and menthol have a considerable share in the global trade of medicinal plants for widespread use in the pharmaceutical, food, cosmetic, and fragrance industries. This study was conducted to investigate the response of M. arvensis var. piperascens Holmes to planting time (fall and spring) under marginal land conditions. Plants were propagated by three-year-old rhizomes. Obtained results showed that the effect of growing seasons was not significant on the agronomic traits and VO yield. However, the effects of six different impressions during the experiment were significant on the studied parameters. The highest plant height (45 cm), fresh biomass (16692 kg ha-1), dry biomass (4736 kg ha-1), leaf dry yield (2816 kg ha-1), and VO yield (158 L ha-1) were observed in the 1st cuttings. The yield components decreased with the plants aging. The lowest values of the mentioned parameters were in the sixth harvest. Moreover, the VO content varied from 4.6-6.1 %. Menthol (52.19-73.53 %) and menthone (3.42-18.89 %) were identified as the most major VO components of M. arvensis. While the menthol percent decreased in the last cuttings, menthone increased correspondingly. Based on the results of this study, it can be suggested that the cultivation of mint in marginal land has a desirable agronomic yield and acceptable chemical properties.