Identification of Healthy and BSR-Infected Oil Palm Trees Using Color Indices

Most of the oil palm plantations have been threatened by Basal Stem Rot (BSR) disease which causes serious economic impact. This study was conducted to identify the healthy and BSRinfected oil palm tree using thirteen color indices. Multispectral and thermal camera was used to capture 216 images of the leaves taken from frond number 1, 9 and 17. Indices of normalized difference vegetation index (NDVI), red (R), green (G), blue (B), near infrared (NIR), green – blue (GB), green/blue (G/B), green – red (GR), green/red (G/R), hue (H), saturation (S), intensity (I) and thermal index (T) were used. From this study, it can be concluded that G index taken from frond number 9 is the best index to differentiate between the healthy and BSR-infected oil palm trees. It not only gave high value of correlation coefficient (R=-0.962), but also high value of separation between healthy and BSR-infected oil palm tree. Furthermore, power and S model developed using G index gave the highest R2 value which is 0.985.

Authors:

• Siti Khairunniza-Bejo
• Yusnida Yusoff
• Nik Salwani Nik Yusoff
• Idris Abu Seman
• Mohamad Izzuddin Anuar

Keywords:

• Oil palm
• image processing
• disease
• leaves.

References:

A. Roslan, and A.S. Idris,“Economic impact of Ganoderma incidence on
Malaysian oil palm plantation – a case study in Johor,” in Oil Palm
Industry Economic Journal, vol. 12, no. 1, pp. 24-30, 2012.
[2] R.H.V. Corley, and P.B. Tinker, The oil palm (Elaeisguineensis Jacq).
Oxford: Wiley-Blackwell, 2004, 4th edition.
[3] R.H.Y. Corley, J.J. Hardon, and B.J. Wood, Oil palm research.
Amsterdam: Elsevier, 1976.
[4] P.D. Turner, Oil Palm Diseases and Disorders. Oxford: Oxford
University Press, 1981.
[5] D. Ariffin, A.S. Idris, and H. Khairuddin, “Confirmation of Ganoderma
infected palm by drilling technique,” in Proc of the PORIM
International Palm Oil Congress: Update and Vision (Agriculture),
Bangi, 1993, pp. 735-738.
[6] A.S. Idris, and R. Rafidah, “Enzyme linked immune sorbent assaypolyclonal
antibody (ELISA-PAb),” MPOB Information Series, no. 430,
pp. 4, 2008.
[7] A.S. Idris, M.S. Mazliham, P. Loonis, and M.B. Wahid,“Gano Sken for
early detection of Ganoderma,”MPOB Information Series, no. 499, pp.
4, 2010.
[8] T.W. Darmono, and Suharyanto, “Detection of basal stem rot disease of
oil palm using polyclonal antibody”,Menara Perkebunan, 67(1), pp. 32-
39, 1999.
[9] H. Santoso, T. Gunawan, R. Jatmiko, W. Darmosarko, and B. Minasny,
“Mapping and identifying basal stem rot disease in oil palms in North
Sumatra with Quickbird Imagery,” Precision Agriculture, 12(2), pp.
233-248, 2011.