Response of Low Frequency Harvesting Systems of Rubber Under Drier Climatic Conditions in Sri Lanka
RESPONSE OF LOW FREQUENCY HARVESTING SYSTEMS OF RUBBER UNDER DRIER CLIMATIC CONDITIONS IN SRI LANKA K.V.V.S. Kudaligama1*, V.H.L.Rodrigo1, K.M.E.P. Fernando2 and P. A. J. Yapa
1
Department of Biochemistry and Physiology, Rubber Research Institute, Sri Lanka 2 Department of Botany, University of Sri Jayewardenepura, Sri Lanka * vskudaligama@yahoo.com, Tel-++ 94 34 2247426, Fax- ++ 94 34 2247427
Abstract
Escalating cost of production (COP) and inadequate supply of skilled harvesters are among the major issues that natural rubber industry face today. Low frequency harvesting (LFH) systems of which trees are tapped in a lesser frequency than once in two days, are considered to be one of the solutions to overcome these issues. With the focus given to expand rubber in drier climates, the present study was aimed to investigate on the yield response of LFH systems, viz. harvesting trees once in three (d3), four (d4) and six (d6) days in the intermediate zone (IZ) with the stimulation protocols developed for the wet zone (WZ). With the decrease in harvesting frequency in IZ, yield per tree per tapping (GTT) increased, however yield per tree per year (YPT) decreased. No such declines were observed in WZ. Stimulation had no negative impact on percentage dry rubber content in latex (%DRC) or incidence of Tapping Panel Dryness. Whilst only the S/2 d3 system is acceptable for IZ in the present form, stimulation protocols are to be revised in other LFH systems. Bark consumption was reduced significantly by LFH resulting in several long-term beneficial effects. Effect of stimulation on latex physiology is also discussed. Keywords: Climate change, Ethephon, Hevea, Low frequency harvesting, Rubber
1. INTRODUCTION Being the second largest plantation crop in the country, rubber (Hevea brasiliensis) covers ca. 122,000 ha and produces ca. 129million kg of raw rubber (ref). More importantly, it provides ca. 500,000 direct and indirect employments. The total export earnings
1
Department of Biochemistry and Physiology, Rubber Research Institute, Sri Lanka 2 Department of Botany, University of Sri Jayewardenepura, Sri Lanka * vskudaligama@yahoo.com, Tel-++ 94 34 2247426, Fax- ++ 94 34 2247427
Abstract
Escalating cost of production (COP) and inadequate supply of skilled harvesters are among the major issues that natural rubber industry face today. Low frequency harvesting (LFH) systems of which trees are tapped in a lesser frequency than once in two days, are considered to be one of the solutions to overcome these issues. With the focus given to expand rubber in drier climates, the present study was aimed to investigate on the yield response of LFH systems, viz. harvesting trees once in three (d3), four (d4) and six (d6) days in the intermediate zone (IZ) with the stimulation protocols developed for the wet zone (WZ). With the decrease in harvesting frequency in IZ, yield per tree per tapping (GTT) increased, however yield per tree per year (YPT) decreased. No such declines were observed in WZ. Stimulation had no negative impact on percentage dry rubber content in latex (%DRC) or incidence of Tapping Panel Dryness. Whilst only the S/2 d3 system is acceptable for IZ in the present form, stimulation protocols are to be revised in other LFH systems. Bark consumption was reduced significantly by LFH resulting in several long-term beneficial effects. Effect of stimulation on latex physiology is also discussed. Keywords: Climate change, Ethephon, Hevea, Low frequency harvesting, Rubber
1. INTRODUCTION Being the second largest plantation crop in the country, rubber (Hevea brasiliensis) covers ca. 122,000 ha and produces ca. 129million kg of raw rubber (ref). More importantly, it provides ca. 500,000 direct and indirect employments. The total export earnings
References: Abraham, P. D., Blencowe, J. W., Chua, S. E., Gomez, J. B., Moir, G. F. J., Pakianathan, S. W., Sekhar, B. C., Southorn, W. A., Wycherley, P. R., 1971. Noval stimulants and procedures in the exploitation of Hevea. I. Introductory review. Journal of Rubber Research Institute of Malaya, 23, 85. Abraham, P. D., Tayler, R. S., 1967. Stimulation of latex flow in Hevea brasiliensis, Exp. Agr. 3, 1. Ahmad Zarin Mat Tasi, Kewi, Chong, Hashim, Ismail, 1991. Low intensity tapping systems and early use of CUT. In: Towards Greater Viability of the Natural Rubber Industry. Rubber Growers’ Conference, Kuala Lumpur, Malaysia July 1991. 189-211. Anon, 2008a. Statistical information on plantation crops, Ministry of Plantation Industries, Colombo, Sri Lanka. Anon, 2008b. Annual report of Central Bank of Sri Lanka. Anon, 2009. Sri Lanka Business Directory, Kurunegala District, North Western province of Sri Lanka. http://www.buyandsell.lk/north-western/kurunegala/index.html%20-%20 [Accessed on 15 May 2010]. Chapman, G. W., 1951. Plant hormones and yield in Hevea brasiliensis, Journal of Rubber Research Institute of Malaya, 13, 167. De Jonge, P., 1955. Stimulation of yield in Hevea brasiliensis, III Further observations on the effects of yield stimulation, Journal of Rubber Research Institute of Malaya, 14, 383. Gomez, J. B., 1983. Physiology of latex (rubber) production, Rubber Research and Development Board of Malaysia, Monograph No 8. Proceedings of the 15th International Forestry and Environment Symposium, 26-27 November 2010. Published by Department of Forestry and Environmental Science, University of Sri Jayewardenepura, Sri Lanka. 68 Kewi, Chong, Sivakumaran, S., 1994. Performance of low frequency tapping systems. Workshop of the exploitation technologies to address current labour problems in the rubber industry, Kuala Lumpur, Malaysia. 47. Nugawela, A., 2001. Exploitation for economic yields. In: L. M. K. Tillekerathne, A Nugawela (Eds.), Handbook of Rubber Volume 1, Rubber Research Institute of Sri Lanka, Agalawatta, Sri Lanka, 176-190. Pushpadas, M. V., Karthikakutty Amma, M., 1980. Agro-ecological requirements. In: Radhakrishnan Pillay, P. N. (Eds.), Hand book of natural rubber production in India, Rubber Research Institute of India, Kottayam, India. 87 – 109. Rao, P. S., Vijayakumar, K. R., 1992. Climatic requirements. In: Sethuraj, M. R., Mathew, N. M. (Eds.), Natural rubber biology, cultivation and technology, Rubber Research Institute of India, Kottayam, India, 220-238. Vijayakumar, K R, 2003. Low frequency tapping to reduce cost of natural rubber production. Indian Rubber Journal, 70, 41. Wijesekera, R. S., Rajapakse, R. A. G. R. R., Somasiri, L. L. W., Tennakoon, N. A., 2004. Hydrological study on deep groundwater aquifers in the coconut growing areas of Kurunegala District. Water Professionals’ Symposium, Colombo, Sri Lanka, October, 2004. Available from: http://www.gissl.lk/WaterProf/2004/acrobatpapers/RS_Wijesekera_18.pdf [Accessed on 15 May 2010] Yogarathnam, N., 2001. Land suitability evaluation, selection and soil conservation. In: Tillekeratne L. M. K., Nugawela A. (Eds.), Hand book of rubber, Agronomy, Rubber Research Institute of Sri Lanka. Proceedings of the 15th International Forestry and Environment Symposium, 26-27 November 2010. Published by Department of Forestry and Environmental Science, University of Sri Jayewardenepura, Sri Lanka. 69