EFFECT OF CLIPPING HEIGHT ON HERB AND ESSENTIAL OIL YIELD OF LEMONGRASS (CYMBOPOGON FLEXUOSUS)

A field experiment was conducted during 1987-90 to determine the speci fic clipping height of lemongrass (Cymbopogon flexuosus Stapf) in rela tion to essential oil yield and its quality. The treatment consisted o f 8 clipping heights, i.e. 5, 10, 15, 20, 25, 30, 35 and 40 cm, from t he ground level. The grass was clipped at I-month intervals. Among the different clipping heights, 20 cm significantly increased the dry her bage and essential oil. Further increase (40 cm) or decrease (5 cm) in clipping height reduced the yield of the 2 parameters. Leaf-area inde x (5.23) increased at clipping height of 20 cm, whereas oil content, d ry weight and carbohydrate content of root increased up to the highest clipping height (40 cm). In comparison to plant stumps, green leaves contained more oil (1.48 and 0.46% for leaves and stumps respectively) and citral (1.8 and 74.7%); and both the contents decreased at lower clipping heights.