Correlation and path-analysis for morpho-economic traits and chemical constituents of essential oil in Corn mint (Mentha arvensis L.) accessions.

Abstract

Mentha arvensis L . which belongs to Lamiaceae family and it is also know as cornmint or japanese mint.The plant as been used for medicinal and aromatic purpose since from ancient time. The present study was planned to estimate the variability among morpho-economic traits, to estimate magnitude of association between essential oil yield and its contributing traits and to determine the direct and indirect effects of various agro-morphic traits on essential oil yield. Experimental materials consist of twenty-nine accessions, which were evaluated for two consecutive years (2016-2017 and 2017-2018) in a randomized complete-block design (RCBD) with two replications. Data were collected on agro-morphic traits and essential oil yield. The results revealed that, the plant height was ranged from 72 cm (MASP-20) to 31cm (MASP-2), herb yield per plot was ranged from 1.83 kg/plot (MASP-13) to 4.36 kg/plot (MASP-12), and essential oil yield was varied from 0.118 kg/plot (MASP-1) to 0.698 kg/plot (MASP-12).The menthol percent was varied from 0.13% (MASP-15) to 73.19 % (MASP-24),menthyl acetate 25.52% (MASP-29) to 0.030% (MASP-18), pulegone 0 % to 75.00% (MASP-22), and limonene was varied from 0.24 %(MASP-29) to 24.89% (MASP-27).The significant and positive association was noticed between essential oil yield and herb yield per plot (0.82**; ** = significant at 1% probability level) and number of branches per plant (0.26*; *= significant at 5% probability level). Among the chemical constituents of essential oil, Limonene percent was positively and significantly correlated with pulegone percent. The path coefficient analysis revealed that herb yield per plot had the highest direct effect on essential oil yield (0.8104). Plant height, number of branches per plant, and herb yield per plot can be used as a selection criterion during selection to develop a high yielding menthol mint chemotypes.