The effect of various planting time on yield and quality of mentha speci̇es in marginal conditions of çukurova region

This study was conducted at the marginal land of experimental area of Field Crops Department, Agricultural Faculty of Çukurova University in 2011, 2012 and 2013 growing season to determine the effect of various planting time (winter and spring) on yield and quality of Mentha species (M. arvensis var. piperascens L. Holmes and M. piperita L. Mitcham). Field trials was arranged in split plot design and randomized complete blocks with three replications. For statistical evaluation, Mentha species, planting time, years and cuttings were as main, sub, sub-sub and sub-sub-sub plots respectively. According to the results, the highest volatile oil ratio and its yield were determined in M. arvensis. The highest fresh and dry herb, dry leaf and dry matter yield, volatile oil ratio and its yield were determined from spring planting. In terms of experimental years, except dry leaf ratio, the other characteristics in 1st year were found higher than 2nd year. Also all of the characteristics values in 1st cuttings were higher than 2nd cuttings. In terms of volatile oil components that determined by GC-MS, the highest menthole ratio was obtained from 2nd cutting of 1st year of winter M. arvensis and the highest menthone ratio was obtained from 1st cutting of 2nd year of spring M. piperita. According to the results of this research under marginal lands conditions of Çukurova region, between two Mentha species that had formed experimental materials, Mentha arvensis produced high volatile oil ratio, volatile oil yield and menthole ratio than Mentha piperita.