Advanced Search
Biosystems Engineering
Rotbart, N., Institute of Agricultural Engineering, ARO, The Volcani Center, P.O. Box 6, Bet-Dagan 50250, Israel
Schmilovitch, Z., Institute of Agricultural Engineering, ARO, The Volcani Center, P.O. Box 6, Bet-Dagan 50250, Israel
Cohen, Y., Institute of Agricultural Engineering, ARO, The Volcani Center, P.O. Box 6, Bet-Dagan 50250, Israel
Alchanatis, V., Institute of Agricultural Engineering, ARO, The Volcani Center, P.O. Box 6, Bet-Dagan 50250, Israel
Erel, R., Gilat Research Center, Agricultural Research Organization, M.P. Negev, 85280, Israel
Ignat, T., Institute of Agricultural Engineering, ARO, The Volcani Center, P.O. Box 6, Bet-Dagan 50250, Israel
Shenderey, C., Institute of Agricultural Engineering, ARO, The Volcani Center, P.O. Box 6, Bet-Dagan 50250, Israel
Dag, A., Gilat Research Center, Agricultural Research Organization, M.P. Negev, 85280, Israel
Yermiyahu, U., Gilat Research Center, Agricultural Research Organization, M.P. Negev, 85280, Israel
VIS-NIR spectroscopy for estimation of Nitrogen (N) content in olive leaves was studied as a tool for efficient fertilisation in olive (Olea europaea) orchards. Olive leaf samples (cv. Barnea) were taken from orchards which had been fertilised with a wide range of N levels. Dried ground leaves, fresh ground leaves and intact leaves were tested. Reflectance measurements were taken using three spectrometers: USB-2000 for VIS-NIR (450-1000 nm) and a LIGA, and a Luminar-5030 for SWIR (1100-1700 nm). Nitrogen concentrations of the same samples were measured analytically as a reference for the spectral analyses, which were conducted by means of partial least square regression (PLSR). The best predictive model for comprehensive in-season and between-season samples (160 samples from three seasons, taken on 18 separate days) was obtained using the Luminar spectrometer using thoroughly ground dried leaves (R2 = 0.91). Classification into three N levels was evaluated and gave an overall accuracy of 0.83 with a kappa of 0.75 (substantial). Intact leaves yielded non-sufficient correlations. The results showed that leaf dehydration improves the model performance significantly and that VIS-NIR spectroscopy might be used for decision-making in fertilisation procedures. Finally, a protocol is suggested for laboratory spectral measurements. © 2012 IAgrE.
Powered by ClearMash Solutions Ltd -
Volcani treasures
About
Terms of use
Estimating olive leaf nitrogen concentration using visible and near-infrared spectral reflectance
114
Rotbart, N., Institute of Agricultural Engineering, ARO, The Volcani Center, P.O. Box 6, Bet-Dagan 50250, Israel
Schmilovitch, Z., Institute of Agricultural Engineering, ARO, The Volcani Center, P.O. Box 6, Bet-Dagan 50250, Israel
Cohen, Y., Institute of Agricultural Engineering, ARO, The Volcani Center, P.O. Box 6, Bet-Dagan 50250, Israel
Alchanatis, V., Institute of Agricultural Engineering, ARO, The Volcani Center, P.O. Box 6, Bet-Dagan 50250, Israel
Erel, R., Gilat Research Center, Agricultural Research Organization, M.P. Negev, 85280, Israel
Ignat, T., Institute of Agricultural Engineering, ARO, The Volcani Center, P.O. Box 6, Bet-Dagan 50250, Israel
Shenderey, C., Institute of Agricultural Engineering, ARO, The Volcani Center, P.O. Box 6, Bet-Dagan 50250, Israel
Dag, A., Gilat Research Center, Agricultural Research Organization, M.P. Negev, 85280, Israel
Yermiyahu, U., Gilat Research Center, Agricultural Research Organization, M.P. Negev, 85280, Israel
Estimating olive leaf nitrogen concentration using visible and near-infrared spectral reflectance
VIS-NIR spectroscopy for estimation of Nitrogen (N) content in olive leaves was studied as a tool for efficient fertilisation in olive (Olea europaea) orchards. Olive leaf samples (cv. Barnea) were taken from orchards which had been fertilised with a wide range of N levels. Dried ground leaves, fresh ground leaves and intact leaves were tested. Reflectance measurements were taken using three spectrometers: USB-2000 for VIS-NIR (450-1000 nm) and a LIGA, and a Luminar-5030 for SWIR (1100-1700 nm). Nitrogen concentrations of the same samples were measured analytically as a reference for the spectral analyses, which were conducted by means of partial least square regression (PLSR). The best predictive model for comprehensive in-season and between-season samples (160 samples from three seasons, taken on 18 separate days) was obtained using the Luminar spectrometer using thoroughly ground dried leaves (R2 = 0.91). Classification into three N levels was evaluated and gave an overall accuracy of 0.83 with a kappa of 0.75 (substantial). Intact leaves yielded non-sufficient correlations. The results showed that leaf dehydration improves the model performance significantly and that VIS-NIR spectroscopy might be used for decision-making in fertilisation procedures. Finally, a protocol is suggested for laboratory spectral measurements. © 2012 IAgrE.
Scientific Publication
You may also be interested in