Rubber Research Institute of Sri Lanka

Ministry of Plantation Industries

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 a Junior Researcher 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. Has published more than 100 scientific publications and honoured by the IRRDB-RI fellowship and the President's Scholarship for Mathematical Programming.

Current research interests

Modeling rainfall and drought dynamics
Statistics for social science research
Climate change and variability

National & International Awards

The Rothamsted International Fellowship, Rothamsted Research, UK - 1997
The President’s Scholarship in Mathematical Programming  - 2002


  • 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.


  • Research support
  • Analysis of time series
  • Devising appropriate methods to analyze social science research
  • Statistical process control
  • Application of GIS and spatial data analysis
  • Statistical methods for on-farm participatory research
  • Statistical methods for on-farm participatory research
  • Analysis of  rainfall and drought dynamics in rubber growing areas

  • Supervising postgraduate and undergraduate students  
  • Training of students from technical colleges and various training institutions
  • Supplying meteorological data collected at the Dartonfield meteorological station and rainfall data from substations on request
  • Wasana Wijesuriya,  D M A P Dissanayake,  H M L K Herath,  S B Karunaratne,  P W Jeewanthi, B R Kulasekera and C S Gurusinghe. (2013). Use of rainfall patterns for effective management of rubber plantations in Eastern, North central and Northern provinces of Sri Lanka. J. Rubber Research Institute of Sri Lanka, 93: 72-88.
  • H M L K Herath, S Samita and Wasana Wijesuriya. (2013). Identification of instability in natural rubber prices in Sri Lanka.  J. Rubber Research Institute of Sri Lanka, 93: 37-50.
  • Wijesuriya, Wasana. (2014). Statistical Information on the Sri Lankan Rubber sector: What is available and where to find?.  The journal of the plastics and rubber institute of Sri Lanka, 14: 47-54.
  • Edirisinghe, J. C.  and W. Wijesuriya. (2014). Spatial Relationships in Choosing to Conserve Soil in Smallholder Rubber Farming.  Journal of Environmental Professionals Sri Lanka: 2014 – Vol. 3 – No. 1 : 22-29.
  • Gunaratne, M.D.N., Wasana Wijesuriya and D.A.B.N. Amarasekera. (2014). Application of multivariate process control (MPC) in the Natural Rubber Industry. Proc. 18th International Forestry and Environment Symposium 2013. University of Sri Jayawardenepura, Sri Lanka. 130p.
  • Jeewanthi, P.W. , Wijesuriya, Wasana and Herath, H.M.L.K. (2014). R codes for calculation of optimum plot size.  Proc. Wayamba International Conference 2014, Wayamba University of Sri Lanka.
  • Keminda Herath, Wijesuriya, Wasana, Samita, S. (2014). An alternative method to use SARIMA-GARCH model on seasonal time series with volatility. Proc. Wayamba International Conference 2014, Wayamba University of Sri Lanka.
  • Wijesuriya, Wasana,  J.K.S. Sankalpa, S.B. Karunaratne, D.M.A.P. Dissanayake, P.W. Jeewanthi and O.V. Abeywardene. (2014). Identifying Rainfall and Drought Dynamics Using Standardized Precipitation Index (SPI): An Application in Non-traditional Rubber Growing Areas in Eastern, North Central and Northern Provinces of Sri Lanka.  5th symposium on PCR.
  • 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.
  • 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.
  • Sankalpa, J.K.S., S. Karunaratne and W. Wijesuriya. (2015). Land suitability evaluation for rubber cultivation using multi criteria decision approach and GIS: Special focus on Ampara district. Proc YSF Symposium 2014, HARTI, Colombo: 175-178.
  • Jeewanthi. P.W., W. Wijesuriya & J.K.S Sankalpa (2015). Use of information on rainfall behavior to assist timely management of agronomic operations in rubber plantations in the Agro Ecological Region – WL1a. Proc YSF Symposium 2014, HARTI, Colombo: 100-103.
  • 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.

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