Rubber Research Institute of Sri Lanka

Ministry of Plantation

Biometry Section

Providing necessary research support to other departments, maintenance of databases, conducting research falling into the discipline of Biometry and involving in collaborative research in the rubber sector are the main objectives of the Biometry section. To provide the best of its service to the clients, the staff of the Biometry section is in a routine process of upgrading their knowledge through a research focus to develop suitable statistical methodologies for the rubber sector.


Principal Research Officer

Mrs B W Wijesuriya, BSc Agric (SL), MPhil (SL), PhD (SL)
wijesuriyawasana[at] , wasanawij[at]

Having obtained the basic degree in BSc Agriculture from the University of Ruhuna, she subsequently obtained the MPhil and PhD in the field of Biostatistics from the Postgraduate Institute of Agriculture, University of Peradeniya, Sri Lanka. Joined RRISL as Assistant Biometrician in 1991 and presently employed as a Principal Research Officer in the Biometry Section. Her current research focuses are developing, modification and application of statistical methods to suit the requirements in Rubber research and also involved in climate change research. Contributed to the rubber industry by developing models for rubber sector information dissemination strategy in the Sri Lanka Rubber Master Plan. Has published more than 150 scientific publications and honoured by the IRRDB-RI fellowship offered by the Rothamsted International of UK and IRRDB. She also received the President’s Scholarship for Mathematical Programming.

Current Research interests
  • Modeling rainfall and drought dynamics
  • Statistics for social science research
  • Climate change and variability
  • Forecasting techniques
National & International Awards
  • The Rothamsted International Fellowship, Rothamsted Research, UK – 1997
  • The President’s Scholarship in Mathematical Programming - 2002
  • International Liaison Officer – Socioeconomic Specialist Group of IRRDB - 2017 October to-date

Research Officer

A M R W S D Rathnayaka, BSc Agric (SL)

He obtained the basic degree in BSc (Agricultural Technology and Management) from the University of Peradeniya in 2019 and currently employed as a Research Officer in the Biometry Section of RRISL. He is reading for a Masters in the field of Applied Statistics from the Postgraduate Institute of Agriculture, University of Peradeniya, Sri Lanka. His current research areas are: application of statistical methods, new computer applications and programming in the rubber sector research and developing new statistical approaches for the rubber industry.

Current Research interests
  • Climate change
  • Industrial statistics
  • Computer applications and programming
Current Research Projects
  • Research support in terms of statistical design, analysis and interpretation.
  • Survey design.
  • Analysis of time series and forecasting.
  • Devising appropriate methods to analyze social science research.
  • Statistical process control.
  • Response surface designs for industrial designs and their analysis and interpretation.
  • Application of GIS and spatial data analysis.
  • Statistical methods for on-farm participatory research.
  • Analysis of rainfall and drought dynamics in rubber growing areas.
Research Highlights
  • Applicability of non-parametric statistical methodologies and Bayesian networks were tested and introduced to analyze and interpret results generated through Participatory Rural Appraisal (PRA).
  • Rainfall patterns, dry spells and shifts in rainfall pattern were identified for the rubber growing areas.
  • Several drought indicators were tested and successfully employed the Standardized Precipitation Index (SPI) for crop management.
  • Used GIS technique to map the drought sequences.
  • Applied a novel forecasting technique (MAPA) for forecasting of economic variables in rubber
  • Assisting researchers in designing of experiments, statistical analysis and interpretation.
  • Survey designing and analysis.
  • Supervising postgraduate and undergraduate students.
  • Training of students from technical colleges and various training institutions.
  • Supplying meteorological data collected at the Dartonfield AGROMET station to the Department of Meteorology.
  • Maintaining the meteorological stations at sub-stations (Moneragala & Kuruwita).
PUBLICATION RECORD Last 5 years 2016-2020
  • Gayan M W H, Wijesuriya B W, Sankalpa J K S, Punyawardene B V R, Premalal S, Herath H M L K, Karunaratne S B, Peiris B L, Amarasekera N. (2016). Comparing the use of Standardized Precipitation Index (SPI) and Standardized Precipitation Evapotranspiration Index (SPEI) for Identifying Rainfall Anomalies in the Wet Zone. Wayamba International Conference 2016: 241p.
  • Padmathilake M A V N, Withanage N S, Dharmadasa R A P I S, Wijesuriya W and Jeewanthi P W (2016). Interference for tapping due to rainfall and effectiveness of rainguards under different rainfall scenarios: A case study in the Dartonfield Rubber Estate. Wayamba International Conference 2016: 138p.
  • Jeewanthi P W, Wijesuriya B W, Sarath Kumara (2016). Application of response surface method for optimizing the efficiency of a process: A case study from centrifuge latex manufacturing process. Wayamba International Conference 2016: 297p.
  • Wijesuriya, B.W., Sankalpa, J.K.S., Liyanaarachchi, L.A.T.S., and Gayan M.W.H. (2016). Drought Indices to Identify Rainfall Anomalies in Rubber Growing Areas of Sri Lanka. CRRI & IRRDB International Rubber Conference, Siem Reap, Cambodia, 21-25 November 2016. 415-427.
  • Gunarathne P.K.K.S., Dissanayake D.M.A.P., Wijesuriya W. and Ranawaka R.A.D. (2016). Evaluation of effectiveness of ‘Training Schools for Latex Harvesting Assistants in the smallholder rubber sector of Sri Lanka: A Case study in Kegalle district. CRRI & IRRDB International Rubber Conference, Siem Reap, Cambodia, 21-25 November 2016. 40-49.
  • Sankalpa, J.K.S., Wasana Wijesuriya, Senani Karunaratne and P G N Ishani. (2017). Use of GIS Geographically Weighted Regression to determine Natural Rubber productivity and their driving forces: A case study from the Kalutara district of Sri Lanka. IRRI & IRRDB International Rubber Conference 2017, Jakarta, Indonesia, 24 p.
  • Sankalpa, J.K.S., Wasana Wijesuriya, Senani Karunaratne and P G N Ishani. (2017). A comparison of spatial interpolation methods in developing yield maps of natural rubber for precision crop production: A case study from smallholder rubber lands in Kalutara district of Sri Lanka. Proc. International Statistics Conference 2017, Taj Samudra Hotel, Colombo, 129 p.
  • Wasana Wijesuriya (2018). Statistical insight improves the interpretability of data generated through participatory approaches: experiences from the smallholder rubber sector of Sri Lanka, IRRDB International Rubber Conference, Ivory Coast.
  • Dissanayake D.M.A.P, B.W. Wijesuriya, P.K.K.S. Gunarathna and R A D Ranawaka (2018). Empowering rubber farmers in non-traditional rubber growing areas of Sri Lanka through knowledge on combating adverse impacts of environment for rubber cultivation: IRRDB International Rubber Conference, Ivory Coast.
  • P.K.K.S. Gunarathne, D.M.A.P. Dissanayake, W. Wijesuriya and R.A.D. Ranawaka (2018). Livelihoods of Rubber Latex Harvesters in Kegalle District: Comparative Analysis of Harvesting Own Lands versus Operating on Hired Basis. In Proceedings of the SLCARP International Symposium, Colombo, Sri Lanka.
  • Jeewanthi P.W., Wijesuriya W. and Amarakoon A.M.C. Identifying Changes in Rainfall Distribution using Standardized Precipitation Index (SPI): An Application in Uva Province Sri Lanka”. Proceeding of second International Conference on Climate Change 2018:5p.
  • Anura Dissanayake, A., Ishani, P.G.N., Gunarathne, P.K.K.S., Ranawaka, R.A.D., Sankalpa, J.K.S., Seneviratne, P. and Wijesuriya, W. (2019) ‘Strategies to prevent evading from rubber planting: Introducing Gliricidia as a fuel wood in smallholder rubber lands of Sri Lanka’, International Rubber Conference 2019, Myanmar.
  • Wijesuriya, W., Herath, H.M.L.K., lshani, P.G.N. and Sankalpa, J.K.S. (2019) ‘Forecasting of Rubbe Prices in the Sri Lankan market using Multiple Temporal Aggregation (MTA)’, International Rubber Conference 2019, Myanmar.
  • Rathnayaka, A.M.R.W.S.D., Samitha, S., and Wijesuriya, W. (2019). Occurrence of Extreme Rainfall Events in Rubber (Heveabrasiliensis) Growing Areas. Proceeding of 5th Annual Sessions of Faculty of Agriculture Undergraduate Research Symposium, University of Peradeniya, Peradeniya, Sri Lanka, Pp.160.
  • Jeewanthi P.W., Wijesuriya W. and Sankalpa J.K.S. (2016). Changes Observed in Rainfall Patterns in Three Major Rubber Growing Areas. Annual Research Colloquium on Agrarian Studies in Sri Lanka 2016: 25p.
  • Liyanaarachchi, L.A.T.S., Wijesuriya, B.W., Sankalpa, J.K.S., Herath, H.M.L.K., Premalal, S., and Karunaratne, S.B. (2017). Identification of Temporal Trends in Rainfall Anomalies of Different Rainfall Seasons in Sri Lanka Using the Standardized Precipitation Index (SPI). Proceeding of 6th Young Scientists Forum, National Science and Technology Commission, Sri Lanka, 20th January 2017. 74-79.
  • Ishani, P G N, J K S Sankalpa and W. Wijesuriya (2017). Sri Lankan Rubber exports performance by major destinations using shift-share analysis. 11th Annual Research Forum, Sri Lanka Agricultural Economics Association, University of Peradeniya. 13 p.
  • Wasana Wijesuriya and Priyani Seneviratne (2017). Preparedness of the Natural Rubber sector against adverse impacts climate change and variability. Proc. Workshop on present status of research activities on climate change adaptations (Ed. B. Marambe). Pp 83-100. Sri Lanka Council for Agricultural Research Policy, Colombo.
  • Ishani, P.G.N., Wijesuriya, W. and Sankalpa, J.K.S. (2019) ‘Can Poverty be reduced through Improvement in Technical Efficiency in the Smallholder Rubber Sector: Case Study from Kegalle District of Sri Lanka, Proceedings of the Seventh Symposium on Plantation Crop Research, 2, pp. 145-153.
  • P.K.K.S. Gunarathne, D.M.A.P. Dissanayake, R.A.D. Ranawaka and Wasana Wijesuriya (2019). Training Induced Adoption Changes in Rubber Harvesting Technologies in Rubber Smallholdings in the Kegalle District of Sri Lanka: Comparative Analysis of Lands Harvested by Owners versus Operating on Hired Basis, Proceedings of the Seventh Symposium on Plantation Crop Research, 2, pp. 135-144.
  • Kuruppu, I.V., Edrisinghe, J.C., Herath, H.M.L.K., Jayasinghe-Mudalige, U.K., Wijesuriya, W., Udugama, J.M.M. and Fernando, A.P.S. (2015). Farmers’ valuation of agro-biodiversity in home gardens: Case study in the Kurunegala district. Journal of Environmental Professionals Sri Lanka, 4: 72-83.
  • Dissanayake, D.M.A.P., P.K.K.S. Gunarathna and W. Wijesuriya. (2016). Evaluation of farmer awareness on rubber cultivation and production technologies in major rubber-growing areas of Sri Lanka. Sri Lanka Journal of food and agriculture SLJFA, Vol. 01 (1): 39-50.
  • Wickramarachchi, A.R., H.M.L.K. herath, U.K. Jayasinghe-Mudalige, J.C. Edirisinghe, J.M.M. Udugama. I.D.M.N. Lokuge and W. Wijesuriya. (2018). An analysis of price behaviour of major poultry products in Sri Lanka. The journal of Agricultural Sciences, Vol. 12 (2): pp 138-148.
  • Sankalpa, J.K.S., Wijesuriya, W. & Ishani, P.G.N. Do rubber-based agroforestry practices build resilience upon poverty incidence? A case study from Moneragala district in Sri Lanka. Agroforest Syst (2020).

For Information

  • Call 1919

Contact Info

  • Rubber Research Institute of Sri Lanka.
  • Dartonfield, Agalawatta. 12200
  • 034 - 2247426, 034 - 2247383
  • 034 - 2248459, 034 - 2295540
  • 034 - 2247427