Spatial Reflectance at Sub-Leaf Scale Discriminating NPK Stress Characteristics in Barley Using Multiway Regression (N-PLS)
نویسندگان
چکیده
Non-destructive stress diagnostics is essential to optimise variable nutrient application with a minimal environmental load. The identifying characteristics when spectrally determining nitrogen, phosphorous and potassium stress in a canopy are dominantly nonspecific symptoms expressed as varying levels of chlorophyll in the leaves. The challenge is spectrally based discrimination between N, P and K stress. This paper introduces a methodology able to discriminate between N, P and K stress symptoms utilising both the spectral and spatial dimension simultaneously. The methodology was tested on spring barley grown under controlled conditions. The spectral range used was 450-1000 nm. Nine spectral measurement were carried out on each plant. The measuring points were spatially located at The authors are solely responsible for the content of this technical presentation. The technical presentation does not necessarily reflect the official position of the American Society of Agricultural Engineers (ASAE), and its printing and distribution does not constitute an endorsement of views which may be expressed. Technical presentations are not subject to the formal peer review process by ASAE editorial committees; therefore, they are not to be presented as refereed publications. Citation of this work should state that it is from an ASAE meeting paper EXAMPLE: Author's Last Name, Initials. 2003. Title of Presentation. ASAE Paper No. 03xxxx. St. Joseph, Mich.: ASAE. For information about securing permission to reprint or reproduce a technical presentation, please contact ASAE at [email protected] or 269-429-0300 (2950 Niles Road, St. Joseph, MI 49085-9659 USA). the tip, middle and base of the three last fully developed leaves. This design generated a fourdimensional data set consisting of the specific plant, the spectral dimension, the plant leaf position, and position on the leaf. Sequential mutiway Partial Least Squares Regression model (N-PLS) analysis with dummy variables was able to correctly classify the four nutrient conditions with 92% accuracy regardless of the respective growth stages within a time window of two weeks. Thus inclusion of the spatial dimension to the spectral dimension was shown to be a promissing nutrient diagnostic tool.
منابع مشابه
Spectral NPK Stress Discrimination in Barley Plants by use of Three Wavebands
Discrimination of nutrient stress condition is the essential step prior to estimating the actual nutrient status using remote sensing. This research introduces a new methodology able to discriminate amongst nonstressed (C) barley plants and N, P, and K deficiency symptoms spectrally using just three narrow reflection bands utilising both the spectral and spatial dimension simultaneously. Nine s...
متن کاملNutrient Stress Discrimination of N, P, and K Deficiencies in Barley Utilising Multi-band Reflection at Sub-leaf Scale
Discrimination of nutrient stress condition is the essential step prior to estimating the actual nutrient status using remote sensing. This research introduces a new methodology able to discriminate amongst non-stressed (C) barley plants and N, P, and K deficiency symptoms spectrally using just three narrow reflection bands utilising both the spectral and spatial dimension simultaneously. Nine ...
متن کاملAssessing Nitrogen Stress in Corn Varieties of Varying Color
Nitrogen (N) is an essential element for crop growth and its accurate assessment in plants is a key to nutrient management. This research was conducted to explore the feasibility of using spectral reflectance to predict nitrogen content in corn plant varieties with varying color. A problem identified by previous researchers is the variability of spectral responses from varieties with different ...
متن کاملClassification of Fusarium-Infected Korean Hulled Barley Using Near-Infrared Reflectance Spectroscopy and Partial Least Squares Discriminant Analysis
The purpose of this study is to use near-infrared reflectance (NIR) spectroscopy equipment to nondestructively and rapidly discriminate Fusarium-infected hulled barley. Both normal hulled barley and Fusarium-infected hulled barley were scanned by using a NIR spectrometer with a wavelength range of 1175 to 2170 nm. Multiple mathematical pretreatments were applied to the reflectance spectra obtai...
متن کاملInvestigation of Leaf Diseases and Estimation of Chlorophyll Concentration in Seven Barley Varieties Using Fluorescence and Hyperspectral Indices
Leaf diseases, such as powdery mildew and leaf rust, frequently infect barley plants and severely affect the economic value of malting barley. Early detection of barley diseases would facilitate the timely application of fungicides. In a field experiment, we investigated the performance of fluorescence and reflectance indices on (1) detecting barley disease risks when no fungicide is applied an...
متن کامل