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Ganesan Vadamalai - One of the best experts on this subject based on the ideXlab platform.
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Selection of a Spectral Index for Detection of Orange Spotting Disease in Oil Palm (Elaeis guineensis Jacq.) Using Red Edge and Neural Network Techniques
Journal of the Indian Society of Remote Sensing, 2019Co-Authors: Kamlesh Golhani, Ganesan Vadamalai, Sk Balasundram, Biswajeet PradhanAbstract:Spectral screening can play an important role in successful detection of Viroid-infected oil palm seedlings from nursery stage prior to transplanting into the field. Coconut cadang–cadang Viroid (CCCVd) is the main causal agent of orange spotting (OS) disease. OS disease is an emerging disease in Malaysian plantation. In this study, a glasshouse experiment was conducted with fifteen CCCVd-inoculated and five healthy oil palm seedlings in the growing season of 2015. Spectral screening was performed using a hyperspectral spectroradiometer, Analytic Spectral Device HandHeld 2 (325–1075 nm). The red edge, a steep gradient in reflectance between red and near-infrared bands (680–780 nm), was used for selection of red edge bands. A maximum point (i.e., 700 nm) and minimum point (i.e., 768 nm) of red edge were selected from healthy and inoculated spectra. Shifts of red edge inflection point from healthy to inoculated spectra were also studied. Four well-known spectral indices, namely simple ratio, red edge normalized difference vegetation index, two-band enhanced vegetation index 2 (EVI2), and chlorophyll index red edge, were evaluated using selected red edge bands. The multilayer perceptron neural network model was used to establish a nonlinear relationship between selected spectral bands and each spectral index. EVI2 was selected as a best spectral index which resulted in zero errors at the training, testing, and validation datasets. The highest coefficient of correlation ( r = 1) was recorded between spectral bands (input values) and EVI2 (target values).
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Coconut Cadang-Cadang Viroid and Coconut Tinangaja Viroid
Viroids and Satellites, 2017Co-Authors: Ganesan Vadamalai, Sathis Sri Thanarajoo, Hendry Joseph, Lih Ling Kong, John W. RandlesAbstract:Coconut Cadang-Cadang Viroid (CCCVd) causes the lethal Cadang-Cadang disease of Coconut palm in the Philippines. Variants of CCCVd are associated with a foliar orange spotting syndrome of African oil palm, showing over 90% sequence identity to CCCVd from Coconut, which are also mechanically transmissible, but still require testing for pathogenicity. Coconut tinangaja Viroid causes the lethal tinangaja disease of Coconut palm in Guam, has about 64% sequence identity to CCCVd, but differs from Cadang-Cadang in symptomatology. Neither disease is under control and their epidemiology is poorly understood. Viroid-like RNAs with sequence identity to CCCVd have been detected by molecular hybridization in palms and other monocotyledonous plants in many South East Asian and South Pacific countries. Their role in palm Viroid epidemiology requires thorough investigation.
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detection of Coconut cadang cadang Viroid sequences in oil and Coconut palm by ribonuclease protection assay
Annals of Applied Biology, 2009Co-Authors: Ganesan Vadamalai, A.a.f.l.k. Perera, D. Hanold, M. A. Rezaian, John W. RandlesAbstract:A ribonuclease protection assay (RPA) has been developed for detecting Coconut Cadang-Cadang Viroid (CCCVd) sequences. An RNA probe complementary to full-length CCCVd246 was used, terminating at nucleotide 65 in the upper conserved region, and linked to a non-Viroid 5′ sequence, which acted as an internal control for ribonuclease activity. Extracts from CCCVd-infected Coconut (Cocos nucifera) and African oil (Elaeis guineensis) palms protected three major fragments of approximately 250, 125 and 50 nt and a variable number of minor fragments. Extracts of healthy Coconut palms, Potato spindle tuber Viroid-infected tomato and transfer RNA did not protect the probe. The approximately 250 nt fragment is predicted to indicate the presence of monomers and dimers of circular CCCVd246, linear CCCVd246 with the same termini as the probe and point mutants of these forms. The origin of smaller protected fragments is discussed. RPA-detected CCCVd sequences in 13 of 18 oil palms surveyed in a commercial plantation in Malaysia. Signal intensity varied between the positive oil palms and was generally lower than in Coconut palms infected with CCCVd. An infection phenotype was implied but not confirmed by the observation that in a group of 10 oil palms with orange leaf spotting, 9 contained CCCVd, whereas in a group of 8 palms without orange spotting, the Viroid was detected in 4. Of four Coconut palms in Sri Lanka shown by dot-blot assay to contain CCCVd-related RNA, one was shown by RPA to be positive for the CCCVd246 sequence. RPA is therefore a robust and sensitive test for CCCVd sequences, and our results show that sequences closely related to CCCVd246 are not confined to the Philippines.
Vadamalai Ganesan - One of the best experts on this subject based on the ideXlab platform.
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Economic Significance of Palm Tree Viroids
'Elsevier BV', 2017Co-Authors: Vadamalai Ganesan, Rodriguez Judith, Randles J WAbstract:The ongoing epidemic of the lethal Cadang-Cadang disease in the Philippines, caused by Coconut Cadang-Cadang Viroid (CCCVd), has killed around 40 million (Mn) Coconut palms over the last century. A survey in 2012–13 showed that the boundary of Cadang-Cadang distribution has not expanded markedly over recent decades. The current incidence is about 700,000 diseased palms and rate of spread is predicted to continue at 0.1%–1.0% per annum. Orange leaf-spotting (OS), a nonlethal disorder of oil palm, is associated with infection by variants of CCCVd. OS has a yield penalty of 25%–50% on individual palms, and overall incidence is estimated to be 1%–5%. Malaysia earns approximately $17.24 billion annually from the oil palm industry, and the national loss from OS is estimated at $25.6–256.2 Mn. Provision of CCCVd-free planting material for new plantations is advocated for raising the yield potential of oil palm. The lethal tinangaja disease, caused by Coconut tinangaja Viroid, remains an uncontrolled disease of Coconut palms in Guam
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Detection of Coconut Cadang-Cadang Viroid (CCCVd) in oil palm by reverse transcription loop-mediated isothermal amplification (RT-LAMP)
'Elsevier BV', 2014Co-Authors: Thanarajoo, Sathis Sri, Kong, Lih Ling, Kadir Jugah, Lau, Wei Hong, Vadamalai GanesanAbstract:A reverse transcription loop-mediated isothermal amplification (RT-LAMP) detected Coconut Cadang-Cadang Viroid (CCCVd) within 60. min at 60. °C in total nucleic acid extracted from oil palm leaves infected with CCCVd. Positive reactions showed colour change from orange to green in the reaction mix after the addition of fluorescent reagent, and a laddering pattern band on 2% agarose gel electrophoresis. Conventional RT-PCR with LAMP primers produced amplicons with a sequence identical to the 297-nt CCCVd oil palm variant with the primers being specific for CCCVd and not for other Viroids such as PSTVd and CEVd. RT-LAMP was found to be rapid and specific for detecting oil palm CCCVd
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An investigation of orange spotting disorder in oil palm
2005Co-Authors: Vadamalai GanesanAbstract:Molecular hybridization of Northern blots of single (1D) and two-dimensional polyacrylamide gels (2D-PAGE) with a ³² P-labelled full length CCCVd₂ ₄ ₆ cRNA probe demonstrated the presence of Coconut cadang - cadang Viroid (CCCVd)-like RNAs in nucleic acid extracts of both symptomatic (orange spotted) and asymptomatic oil palms in commercial plantations in Malaysia. Compared with CCCVd in Coconut these CCCVd-like RNAs seemed to be present at low concentration in the oil palm samples as shown by the weak hybridization signals observed in the oil palm samples even when large amounts of nucleic acid extract (leaf fresh weight equivalent of 20-100 g) were loaded onto the gel. Ribonuclease protection assay (RPA) was found to be more sensitive in detecting low concentrations of the CCCVd-like RNAs in the oil palm samples than Northern blots as shown by the higher percentage of positive samples. RPA showed that 90 % of the symptomatic and 50 % of asymptomatic palms from Malaysia had RNAs which protected the ³²P-labelled full length CCCVd antisense probe and produced a similar RPA pattern to that of CCCVd. RPA results also indicated that there were mismatches in the sequence of the CCCVd-like RNAs in the oil palms compared to CCCVd from Coconut. RT-PCR amplification of CCCVd-like RNAs from an asymptomatic palm was only successful when nucleic acids were partially purified using 1D or 2D-PAGE. RNAs eluted from the circular region of 2D-gels of the asymptomatic palm were amplified to a low concentration using CCCVd-specific primers but re-amplification of these first round RT-PCR products was needed for detection of the amplicons by ethidium bromide staining. No amplified product was obtained from a symptomatic palm. Cloning and sequencing of the RT-PCR products from the asymptomatic oil palm produced 20 clones of five sizes comprising 297 nt (OP₂₉₇), 293 nt (OP₂₉₃), 270 nt (OP₂₇₀), 232 nt (OP₂₃ ₂) and 165 nt (OP₁₆₅). 71 % of the clones were OP₂₉₇. Comparison of OP₂₉₇, OP₂₉₃, and OP₂₇₀ with genome database sequences showed high sequence similarity with CCCVd₂₉₆. OP₂₉₇. OP₂₉₃, OP₂₇₀ had 98 %, 97 % and 90 % sequence similarity with CCCVd₂₉₆ respectively. OP₂₃₂ and OP₁₆₅ also had high sequence similarity with parts of CCCVd ₂₄₆ with which they were aligned. Because an arbitrary level of 90 % sequence similarity is accepted as separating Viroid species from variants, OP₂₉₇ , OP₂₉₃ and OP₂₇₀ can be considered as variants of CCCVd. No variants of the ' fast ' CCCVd ₂ ₄ ₆ form were obtained. The consensus OP₂₉₇ sequence had single base substitutions or additions at 5 sites, OP₂₉₃ had substitutions, additions or deletions at 8 sites, and OP₂₇₀ had substitutions at 4 sites as well as deletion of a 26 nt repeat at the right terminus, producing a predicted branched secondary structure. Compared with CCCVd₂₉₆ , all variants substituted (C-U) at nt 31 in the pathogenicity domain and (A-C) at nt 175 in the right hand terminal domain. The presence of sequences similar to OP₂₃₂ and OP₁₆₅ has not been reported for CCCVd. Analysis of DNA extracted from both symptomatic and asymptomatic oil palms from Malaysia by nested PCR using universal primers sets to amplify the 16S rRNA operon showed the presence of phytoplasma-like DNAs in both sets of samples. They were also detected in DNA extracted from oil palm seedlings maintained at the Waite campus but not in the other palm species maintained in the glasshouse. RFLP analysis of phytoplasma-like DNAs gave a different pattern than that expected for Australian grapevine yellows phytoplasma. The phytoplasma - like DNAs were also not related to lethal yellowing phytoplasma (LYp) as PCR analysis with LYp specific primers did not produce any amplicon. No association with OS was found and so they were not characterised further. CCCVd-infected Coconut leaf collected in the Philippines contained two short interfering RNAs (siRNA) approximately 20 nt and 25 nt in size. A high stringency wash of the Northern blots failed to remove the hybridisation signal suggesting that these siRNAs had sequences closely similar to CCCVd. The siRNAs were present in all stages of the Cadang-Cadang and also samples with the 'brooming' symptom. siRNAs are regarded as a marker for post-transcriptional gene silencing (PTGS) in plants infected by Viroids but the results obtained were insufficient to determine whether PTGS regulates the accumulation of CCCVd. This is the first report that a Viroid closely related to CCCVd occurs in oil palm, and in a region outside the Philippines, the country where CCCVd is thought to be contained. The implications for quarantine matters are discussed.Thesis (Ph.D.) -- University of Adelaide, School of Agriculture and Wine, 2005
Thanarajoo, Sathis Sri - One of the best experts on this subject based on the ideXlab platform.
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Detection of Coconut Cadang-Cadang Viroid (CCCVd) in oil palm by reverse transcription loop-mediated isothermal amplification (RT-LAMP)
'Elsevier BV', 2014Co-Authors: Thanarajoo, Sathis Sri, Kong, Lih Ling, Kadir Jugah, Lau, Wei Hong, Vadamalai GanesanAbstract:A reverse transcription loop-mediated isothermal amplification (RT-LAMP) detected Coconut Cadang-Cadang Viroid (CCCVd) within 60. min at 60. °C in total nucleic acid extracted from oil palm leaves infected with CCCVd. Positive reactions showed colour change from orange to green in the reaction mix after the addition of fluorescent reagent, and a laddering pattern band on 2% agarose gel electrophoresis. Conventional RT-PCR with LAMP primers produced amplicons with a sequence identical to the 297-nt CCCVd oil palm variant with the primers being specific for CCCVd and not for other Viroids such as PSTVd and CEVd. RT-LAMP was found to be rapid and specific for detecting oil palm CCCVd
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Rapid detection, accumulation and translocation of Coconut Cadang-Cadang Viroid variants in oil palm
2014Co-Authors: Thanarajoo, Sathis SriAbstract:Coconut Cadang-Cadang Viroid (CCCVd) is the causal agent of the lethal Coconut Cadang-Cadang disease in the Philippines. CCCVd variants were also found in Malaysian oil palm, but in low concentration and difficult to detect. Palms infected with CCCVd variants were associated with orange spotting (OS) disorder and it was estimated that the average yield from the OS-affected palms was 25-50% lower than the healthy palms. Existing diagnostic methods such as hybridization assay and Reverse transcription polymerase chain reaction (RT-PCR) methods are able to detect CCCVd variants in oil palms; however they are laborious, insensitive and time-consuming. In addition, the relationship between CCCVd sequence variation and Viroid accumulation has not been studied. In view of this, the present research was undertaken to produce a simple and rapid detection of CCCVd variants using reverse transcription Loop-mediated isothermal amplification (RT-LAMP) method. Besides that, CCCVd accumulation between two different variants together with movement in inoculated oil palm seedlings was studied using real-time PCR. Simultaneously, the pathogenicity of the two different variants was observed in the inoculated seedlings. CCCVd variants were successfully detected in infected samples as early as 60 min at 60 °C using the primer C2.1. Positive reactions of RT-LAMP showed colour change from orange to green after addition of a fluorescent reagent. The RT-LAMP products generated a laddering pattern on 2% agarose gel electrophoresis with bands of different sizes. The optimal condition for RT-LAMP amplification of CCCVd RNAs from oil palm was at 60 °C for 60 min with 6.0 mM MgSO4, 0.8 M betaine, 2.4 mM dNTPs, 1.6 μM of each inner primer FIP and BIP, 0.4 μM each of outer primer B3 and F3 and 8U Bst DNA polymerase. The sensitivity of both RT-PCR and RT-LAMP was found to be equal. The RT-LAMP primers were specific in detecting CCCVd since they did not amplify other Viroids that were used in the specificity test. CCCVd were also detected in some of the random field samples collected. The BLAST program results showed that the amplified product of RT-LAMP was indeed a variant of CCCVd246OP. For Viroid accumulation study, two variants of CCCVd (CCCVd246OP and CCCVd293OP) were inoculated into 10 three month old oil palm seedlings each, with 10 control seedlings. A RT-PCR and sequencing was carried out to characterise the CCCVd variants obtained from the inoculated seedlings at different time intervals. CCCVd was detected three months after inoculation in low concentrations. The Viroid titre showed that the accumulation of the CCCVd variant in the inoculated seedlings fluctuated without any distinct increasing or decreasing pattern. The results of sequencing analysis showed that CCCVd246OP (Genbank: HQ608513.1) was characterised from seedlings inoculated with CCCVd293OP plasmids. In addition, a 246-nt sequence was also recovered from the symptomatic (OS) seedling with 99% sequence similarity to CCCVd246OP, which confirmed the pathogenicity of this 246-nt CCCVd variant. In Viroid movement study, the CCCVd246OP variant was inoculated into 12 seedlings. The seedlings were sampled every three months with three replicates; separating the leaves, stems and roots. CCCVd was detected in the leaves, stems and roots of the oil palm seedlings after three, six, nine and twelve months of inoculation. The quantification showed that CCCVd load varied in different parts of the seedlings, with higher concentrations in the stems and leaves as compared to the roots
Kamlesh Golhani - One of the best experts on this subject based on the ideXlab platform.
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Selection of a Spectral Index for Detection of Orange Spotting Disease in Oil Palm (Elaeis guineensis Jacq.) Using Red Edge and Neural Network Techniques
Journal of the Indian Society of Remote Sensing, 2019Co-Authors: Kamlesh Golhani, Ganesan Vadamalai, Sk Balasundram, Biswajeet PradhanAbstract:Spectral screening can play an important role in successful detection of Viroid-infected oil palm seedlings from nursery stage prior to transplanting into the field. Coconut cadang–cadang Viroid (CCCVd) is the main causal agent of orange spotting (OS) disease. OS disease is an emerging disease in Malaysian plantation. In this study, a glasshouse experiment was conducted with fifteen CCCVd-inoculated and five healthy oil palm seedlings in the growing season of 2015. Spectral screening was performed using a hyperspectral spectroradiometer, Analytic Spectral Device HandHeld 2 (325–1075 nm). The red edge, a steep gradient in reflectance between red and near-infrared bands (680–780 nm), was used for selection of red edge bands. A maximum point (i.e., 700 nm) and minimum point (i.e., 768 nm) of red edge were selected from healthy and inoculated spectra. Shifts of red edge inflection point from healthy to inoculated spectra were also studied. Four well-known spectral indices, namely simple ratio, red edge normalized difference vegetation index, two-band enhanced vegetation index 2 (EVI2), and chlorophyll index red edge, were evaluated using selected red edge bands. The multilayer perceptron neural network model was used to establish a nonlinear relationship between selected spectral bands and each spectral index. EVI2 was selected as a best spectral index which resulted in zero errors at the training, testing, and validation datasets. The highest coefficient of correlation ( r = 1) was recorded between spectral bands (input values) and EVI2 (target values).
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Early detection of orange spotting disease in oil palm using red edge parameters
2018Co-Authors: Kamlesh GolhaniAbstract:Viroids are single-stranded, low molecular weight, circular RNA between 246 and 401 nucleotides that lacks a protective protein coat. Viroids have only been found in the plants. Coconut Cadang-Cadang Viroid (CCCVd; Genus CocadViroid, Family PospiViroidae) is one of the known species of Viroids that has been reported to cause Orange Spotting (OS) disease in the oil palm (Elaeis guineensis Jacq.; Arecaceae). OS disease is an emerging oil palm disease in Malaysia. Variants of CCCVd have been reported in both symptomatic and asymptomatic oil palm. Currently, there is no direct control measure reported that can be recommended to control OS disease. Replacement of the infected plants is the only measure to reduce losses. Molecular marker techniques are used to detect CCCVd-infected plants. But these techniques are destructive and typically take a longer time in molecular analysis and sequence characterisation. Therefore, for early disease detection, visible-near infrared spectroscopy was employed for the first time at the leaf scale to screen oil palm seedlings using a hand-held spectroradiometer. Glasshouse experiment was conducted on three-month-old inoculated and healthy oil palm seedlings for a duration of four months in two different years, 2015 and 2017. In this research, oil palm seedlings were inoculated with a CCCVd oil palm variant (OP246), and an ASD spectroradiometer was employed to measure reflectance from inoculated and control seedling. In particular, the red edge region (680-780 nm), which has been frequently shown to indicate plant stress, was investigated for selection of red edge wavebands, red edge indices, and development of the Orange Spotting Disease Index (OSDI) using red edge parameters. Firstly, using a standard foreoptic with a 25° Field of View (FOV), two red edge wavebands (i.e. 680 nm and 754 nm) were identified. Their reflectance sensitivity was also examined. Secondly, using a contact probe, two other red edge wavebands (i.e., 700 nm and 768 nm) and a red edge index (i.e., Enhanced Vegetation Index 2) were identified. Finally, a simple ratio, i.e. the sum of the first derivative spectra of right side – Red Edge Point (REP) to the sum of the first derivative spectra of left side – REP of the red edge region, was developed as an OSDI. The OSDI values between experiment batch of 2015 and 2017 demonstrated a strong correlation (r = 0.96). The OSDI is a first spectral index developed for early detection of OS disease at the leaf scale and can be tested at canopy scale in the future. This study has proved that OS disease can be detected at an early stage using a hand-held spectroradiometer.
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Use of reflectance spectroscopy as a tool for screening Viroid-inoculated oil palm seedlings
'Medwin Publishers', 2017Co-Authors: Kamlesh Golhani, K. S. Balasundram, G. Vadamalai, B. PradhanAbstract:Reflectance spectroscopy was assessed as a new diagnostic tool for screening oil palm (Elaeis guineensis Jacq.) seedlings inoculated with Coconut Cadang-Cadang Viroid (CCCVd). This study was aimed at non-destructive diagnosis of Orange Spotting (OS) disease of oil palm under glasshouse conditions. Leaf reflectance (in the detection range of 325-1075 nm) was acquired from oil palm seedlings with and without inoculation (control) of CCCVd. Spectral reflectance was measured at 15 and 30 days after inoculation using a non-imaging spectroradiometer, ASD FieldSpec® HandHeld™ 2. The red-edge region (680-780 nm) was investigated, and two spectral bands (i.e. 680 nm and 754 nm) were selected. Reflectance Sensitivity (RS) analysis was performed over these spectral bands. The far red band at 680 nm was found to be markedly sensitive to CCCVd infection while the spectral band at 754 nm was found to be insensitive. The 680 nm band gave an RS of 35.4% while the 754 nm band registered an RS of -5%. This study demonstrates the potential of screening CCCVd infection at an early stage (nursery establishment) non-destructively
Pradhan B - One of the best experts on this subject based on the ideXlab platform.
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Selection of a Spectral Index for Detection of Orange Spotting Disease in Oil Palm (Elaeis guineensis Jacq.) Using Red Edge and Neural Network Techniques
'Springer Science and Business Media LLC', 2019Co-Authors: Golhani K, Sk Balasundram, Vadamalai G, Pradhan BAbstract:© 2019, Indian Society of Remote Sensing. Spectral screening can play an important role in successful detection of Viroid-infected oil palm seedlings from nursery stage prior to transplanting into the field. Coconut cadang–cadang Viroid (CCCVd) is the main causal agent of orange spotting (OS) disease. OS disease is an emerging disease in Malaysian plantation. In this study, a glasshouse experiment was conducted with fifteen CCCVd-inoculated and five healthy oil palm seedlings in the growing season of 2015. Spectral screening was performed using a hyperspectral spectroradiometer, Analytic Spectral Device HandHeld 2 (325–1075 nm). The red edge, a steep gradient in reflectance between red and near-infrared bands (680–780 nm), was used for selection of red edge bands. A maximum point (i.e., 700 nm) and minimum point (i.e., 768 nm) of red edge were selected from healthy and inoculated spectra. Shifts of red edge inflection point from healthy to inoculated spectra were also studied. Four well-known spectral indices, namely simple ratio, red edge normalized difference vegetation index, two-band enhanced vegetation index 2 (EVI2), and chlorophyll index red edge, were evaluated using selected red edge bands. The multilayer perceptron neural network model was used to establish a nonlinear relationship between selected spectral bands and each spectral index. EVI2 was selected as a best spectral index which resulted in zero errors at the training, testing, and validation datasets. The highest coefficient of correlation (r = 1) was recorded between spectral bands (input values) and EVI2 (target values)
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Estimating chlorophyll content at leaf scale in Viroid-inoculated oil palm seedlings (Elaeis guineensis Jacq.) using reflectance spectra (400 nm–1050 nm)
'Informa UK Limited', 2019Co-Authors: Golhani K, Sk Balasundram, Vadamalai G, Pradhan BAbstract:© 2019, © 2019 Informa UK Limited, trading as Taylor & Francis Group. Orange Spotting (OS) is an emerging disease in oil palm (Elaeis guineensis Jacq) that has been associated with Coconut Cadang-Cadang Viroid (CCCVd; CocadViroid, PospiViroidae). This study was aimed at selecting efficient wavebands in the Visible/near infrared (VNIR) spectrum (400–1050 nm) for estimation of chlorophyll content in CCCVd-inoculated oil palm seedlings. The VNIR spectrum is most sensitive to chlorophyll stress and able to differentiate between healthy and diseased plants. Therefore, a greenhouse experiment was conducted to remotely sense the chlorophyll content using a hyperspectral hand-held spectroradiometer (Analytical Spectral Device (ASD) FieldSpec–II) and a portable chlorophyll meter (Minolta Soil-Plant Analysis Development (SPAD)−502). FieldSpec–II provides reflectance spectra with narrow and contiguous wavebands while SPAD-502 churns out SPAD readings corresponding to chlorophyll content. Interval Partial Least Squares (iPLS) model was used to assess the relationship between independent variable (spectra) and dependent variable (SPAD readings). Five different spectral datasets (i.e. raw spectra, first-order derivatives, Savitzky-Golay smoothing, Multiplicative Scatter Correction (MSC), and standard normal transformation) were investigated. Results showed that the MSC dataset yielded the most accurate estimation with a root mean square error of prediction of 3.70% and a correlation coefficient for prediction of 0.72. A total of thirty wavebands within a range between 601 nm and 630 nm was selected. This work showed that VNIR spectra has the potential to diagnose OS disease in oil palm using the iPLS regression method. This is completely a new application of hyperspectral remote sensing for the oil palm industry, particularly in the domain of plant protection