Effect of manure and plant spacing on crop growth, yield and oil-quality of Curcuma aromatica Salisb. in mid hill of western Himalaya

Curcuma aromatica is found as wild species throughout India. Its oil is used in the pharmaceutical and allied industries. The studies were conducted in mid-hills of Himalaya, Himachal Pradesh, India during 2001-2004 to evaluate the effect of plant spacing (25 cm x 25 cm, 50 cm x 25 cm and 50 cm x 50 cm) and farm yard manure (FYM -15, 22.5, 30 and 37.5 t ha-1) on growth, yield and quality of oil from C. aromatica. Observations were recorded on plant height, number of plantlets per plant, leaf length:breadth ratio, leaf area density, relative growth rate (RGR), crop growth rate (CGR) and oil content (on dry weight basis). Constituents of the oil from first order and second order rhizomes were estimated separately using gas-liquid chromatography (GLC). The crop responded significantly to different plant spacing. Plant height increased with reduction in plant spacing from 50 cm x 50 cm to 25 cm x 25 cm, whereas the number of plantlets followed the reverse trend. Leaf length:breadth ratio and leaf area density showed an increasing trend with closer spacing. Wider plant spacing provided higher fresh rhizome yield owing to higher number of plantlets, RGR and CGR. Application of FYM did not affect plant growth significantly. Interaction of plant spacing and FYM level showed higher CGR value at 50 cm x 50 cm spacing with FYM level of 22.5 t ha-1, in the second year and from initial to second year. Variation in plant spacing and FYM level did not influence the oil content as well as major oil constituents. The first order rhizomes had higher oil content than the second order rhizomes. Application of 22.5 t ha-1 of FYM provided higher oil yield (234.4 kg ha-1) as compared to 15.0 t ha-1 of FYM (174.1 kg ha-1). Also, oil yield was maximum at 50 cm x 50 cm spacing (213.5 kg ha-1) as compared to closer spacing of 25 cm x 25 cm (191.6 kg ha-1). The pooled oil constituents of the first order and second order rhizomes showed increment in 1,8 cineole content with increase in plant spacing from 25 cm x 25 cm (14%) to 50 cm x 50 cm (17%). Irrespective of the treatments, camphor was the major compound followed by 1,8 cineole and isobornyl alcohol.