Influence of harvest duration on the yields of rhizome, root, shoot and their oils in Alpinia galanga (Linn.) Willd.
P.P. Joy, J. Thomas, Samuel Mathew and Baby P. Skaria Kerala Agricultural University, Aromatic and Medicinal Plants Research Station Odakkali, Asamannoor-683 549, Ernakulam, Kerala, India.
Abstract A study on the optimum time of harvest in Alpinia galanga (Linn.) Willd. at the Aromatic and Medicinal Plants Research Station, Odakkali during 1995-1999 revealed that harvesting the crop at 42 months after planting was the best for realising maximum rhizome (45.4 t/ha) and oil (127.4 l/ha) yields and oil of good quality (27.1% cineole). A substantial quantity of oil (127.4 l/ha) could also be obtained from the roots (19.5 t/ha) at 39 months after planting. The shoot yield (40.5 t/ha) and shoot oil yield (70.6 l/ha) were highest at 18 months after planting. Alpinia galanga reached a maximum height of 129.4 cm with more than 48 tillers/clump and 13 leaves/tiller in the experimental location.
Key words: Alpinia galanga, rasna, harvest duration, rhizome and oil yield, essential oil Introduction Alpinia galanga (Linn.) Willd. or greater galangal is known as ‘rasna’ in Sanskrit, ‘kulainjan’ in Hindi and ‘chittaratha’ in Malayalam. It is a perennial herb cultivated for its aromatic and medicinal rhizome. It is distributed in India, China, Myanmar, Nepal and southeast Asia. Charaka includes rasna in the Vayasthapana varya, the group of drugs that are capable of maintaining the youthful vigour and strength. It is one of the ingredients of medicated “Pan” used for masking the foul smell of the mouth and getting relief in throat inflammation. In Ayurveda, “Rasna-saptak-kwath” and “Rasna-adikamath” are used as antiinflammatory decoctions. In Unani, it is an ingredient of aphrodisiac preparations, “Majun Mugawivi ma Mumsik”, “Majun Samagh”, and antispasmodic nervine tonic “Majun Chobchine” and “Lubab Motadil”. It is also used in “Arq Pan” as a cardiac stimulant and carminative 5. The drug stimulates digestion, purifies blood and improves voice 3. The rhizomes are bitter, acrid, thermogenic, aromatic, nervine tonic, stimulant, revulsive, carminative, stomachic, disinfectant, aphrodisiac, expectorant, broncho-dilator, antifungal, febrifuge, antiinflammatory and tonic 6. Rhizome is diuretic and hypothermic. Seed is antiulcerative 4. From green rhizomes, pale yellow oil with a pleasant odour can be obtained on distillation. The essential oil yielded 5.6% cineole, 2.6% methyl-cinnamate and sesquiterpenes. Asolkar et al 1 isolated 18 monoterpenes of which -pinene (22.5%), - 1 pinene (36.7%) and limonene (13.8%) were the major compounds. Charles et al 2 characterised twelve compounds by GC/MS in A. galanga. The major compound was myrcene: 94.51% in rhizome and 52.34% in leaves. Though the plant is adapted to tropical climate and huge demand exists for its rhizomes, no attempt has been made to develop its cultivation technology. Presently the bulk of the demand is met from wild source where the plant grows as a perennial herb. Therefore, the present field experiment was conducted to find the right time of harvest to obtain optimum yields of rhizome and oil. Materials and Methods This study was carried out at the Aromatic and Medicinal Plants Research Station (AMPRS), Odakkali for four years from 1995 to 1999. The experiment was laid in randomised block design with 15 harvest stages as the treatments (harvesting at 3 month intervals from 6 months after planting till 48 months) which was replicated thrice. The soil had a pH of 5.50 and was low in N, high in P and medium in K. The crop was planted at 40x30cm spacing with the onset of monsoon in June. Farm yard manure was applied at 30t/ha/year. No irrigation was given to the crop through out the period of study. Growth and yield observations were recorded at the time of each harvest. The data for the four years were pooled and statistically analysed. The plant materials were hydrodistilled for 5 hours in Clevenger’s apparatus for extracting the essential oil. Components of the essential oil were determined using a gas chromatograph (Chemito model 8510) equipped with flame ionisation detector. The constituents of the oil were separated on a 10 feet long stainless steel packed column loaded with 5% SE-30 on 80-100 mesh chromosorb-W using nitrogen as the carrier gas at a flow rate of 30ml/min. The oven was programmed to heat from the initial temperature of 110C to 220C at the rate of 3C/min. The injection and detection temperatures were 270C. Cineole was identified based on coincidence of retention time with that of authentic standard. Quantification was done by area normalisation. Other components of oil could not be identified for want of reference compounds. Results and Discussion The plant height increased until 42 months of planting beyond which there was no further increase (table 1). The number of tillers/clump could be recorded only up to 27 months, after which, the individual hills were not distinguishable as they merged with each other. The number of tillers/clump increased with advancement of time. The number of leaves/tiller ranged from 5.2 to 13.3 and the maximum number was recorded at 36 months.
2 On an average Alpinia grew to a height of 98cm and produced 24 tillers/clump/year and 10 leaves/tiller. A few pests and diseases (0-9 scale scores) were noticed which were not serious enough to take control measures. The pests observed were shoot borers, leaf eating caterpillars and leaf miners particularly during the early tender stages of growth and development (January to May). The fungal diseases, namely, blight and leafspot were noticed through out the period of growth. The yield of rhizome reached a maximum of 45.4 t/ha at 42 months after planting (Figure 1). The yield of rhizome oil also exhibited a similar trend. The maximum rhizome oil yield recorded was 127.4 l/ha. The gas chromatograms of rhizome oil showed that cineole, the major component in the oil varied from 13.5% to 42.0% and the cineole content at 36-42 months stage was relatively high (Table 1). The root yield reached a maximum of 19.5 t/ha at 39 months (Figure 1). Root oil yield also reached a maximum of 127.4 l/ha at 39 months. The oil content in the root was almost three times that of the rhizome. Therefore, though the root yield was less than rhizome yield, the maximum root oil yield was equal to that of maximum rhizome oil yield. Thus, the root is a very important part of Alpinia. The shoot yield reached a maximum at 18 months and thereafter remained unchanged (Table 1). The shoot oil yield was maximum (70.59 l/ha) at 18 months after planting but declined thereafter due to a decrease in the oil content. This field investigation revealed that highest shoot, root and rhizome yields of Alpinia galanga can be obtained by harvesting the crop at 18, 39 and 42 months after planting under Kerala conditions.
Table 1. Growth and yield parameters and pest and disease scoring of Alpinia galanga as influenced by time of harvest 3 Time of Plant Tillers Leaves Pest Disease Rhizome Root oil Shoot oilCineole in harvest height per per scoring scoring oil recovery recovery rhizome (months) (cm) clump tiller (0-9 (0-9 recovery (%) (%) oil (%) (No.) (No.) scale) scale) (%)
4 6 37.7 10.4 5.6 2.3 0 0.16 0.33 0.12 35.14 9 54.0 12.8 8.3 3.0 1.0 0.11 0.40 0.12 20.56 12 77.5 25.4 9.7 0 0.6 0.16 0.29 0.16 42.04 15 98.1 28.5 9.7 0 1.3 0.23 0.29 0.18 35.41 18 110.9 34.2 10.8 0.3 3.0 0.31 1.14 0.18 17.80 21 105.4 38.4 10.9 0 3.3 0.21 0.56 0.06 18.80 24 97.3 46.0 11.7 0 2.3 0.24 0.57 0.07 24.25 27 99.6 48.3 8.2 0 3.0 0.22 0.36 0.07 27.46 30 104.1 - 9.0 0 3.6 0.28 0.74 0.09 13.54 33 119.5 - 10.3 0 5.0 0.23 0.59 0.05 30.93 36 111.5 - 13.2 0 4.6 0.23 0.49 0.05 21.01 39 116.5 - 9.2 0 3.6 0.24 0.66 0.12 28.90 42 129.4 - 11.3 0 3.6 0.28 0.66 0.12 27.10 45 109.4 - 9.8 0 1.6 0.21 0.62 0.10 28.90 48 94.0 - 5.2 0 2.3 0.20 0.49 0.11 38.69 Mean 97.7 30.5 9.5 - 2.6 0.22 0.55 0.11 27.37 CD 0.05 20.56 15.10 1.63 - NS 0.054 0.159 0.039 --
Acknowledgements This experiment was conducted as a part of the ad-hoc research scheme entitled Standardisation of agrotechniques in lesser known aromatic and medicinal plants of Zingiberaceae with financial assistance from the Indian Council of Agricultural Research. References 1. Asolkar, LV, Kakkar, KK and Chakre, OJ. 1992. Second Supplement to Glossary of Indian Medicinal Plants with Active Principles Part I (A-K). (1965-81). Publications and Informations Directorate (CSIR), New Delhi. 414p. 2. Charles, DJ, Simon, JE and Singh, NK. 1992. The essential oil of Alpinia galanga Willd. Journal of Essential Oil Research, 4 (1): 81-82. 3. Chunekar, KC. 1982. Bhavaprakashanighantu of Sri Bhavamishra. Commentary, Varanasi (in Hindi). 4. Husain, A, Virmani, OP, Popli, SP, Misra, LN, Gupta, MM, Srivastava, GN Abraham, Z and Singh, AK. 1992. Dictionary of Indian Medicinal Plants. CIMAP, Lucknow, India.546p. 5. Thakur, RS. Puri, HS and Husain, A. 1989. Major Medicinal Plants of India, CIMAP, Lucknow, India.pp.50-52. 6. Warrier, PK, Nambiar, VPK and Ramankutty, C. 1993. Indian Medicinal Plants. Vol.3. Orient Longman Ltd., Madras.
5 50 Root Rhizome Shoot 45 40 ) a
h 35 / t (
30 d l e 25 i y 20 h s e 15 r F 10 5 0 6 9 12 15 18 21 24 27 30 33 36 39 42 45 48
Time of harvest (months)
Fig.1. Yields of Alpinia galanga as influenced by time of harvest
140 Root Rhizome Shoot 120
) 100 a h / l (
80 d l e
i 60 y
l i 40 O 20 0 6 9 12 15 18 21 24 27 30 33 36 39 42 45 48 Time of harvest (months)
Fig. 2. Oil Yields of Alpinia galanga as influenced by time of harvest
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