TY - JOUR
T1 - Hyperspectral reflectance and indices for characterizing the dynamics of crop–weed competition for water
AU - Ronay, Inbal
AU - Ephrath, Jhonathan E.
AU - Eizenberg, Hanan
AU - Blumberg, Dan G.
AU - Maman, Shimrit
N1 - Funding Information: We thank the research team from the Earth and Planetary Image Facility (EPIF) for their collaborative effort during the data collection, with a special thanks to Adi Berman. We also thank the Albert Katz International School for Desert Studies (AKIS) for their scholarship. Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2021/2/1
Y1 - 2021/2/1
N2 - Understanding the spectral characteristics of crops in response to stress caused by weeds is a basic step in improving the precision of agricultural technologies that manage weeds in the field. This research focused on the competition between corn (Zea mays) and redroot pigweed (Amaranthus retroflexus), a common weed that strongly reduces corn yield. The aim of this research was to characterize the physiological changes that occur in corn during early growth because of crop–weed competition and to examine the ability to detect the effect of competition through hyperspectral measurements. A greenhouse experiment was conducted, and corn plants were examined during early growth, with and without weed competition. Hyperspectral measurements were combined with physiological measurements to examine the reflectance and photosynthetic activity of corn. Changes were expected to appear mainly in the short-wave infrared region (SWIR) due to competition for water. Relative water content (RWC), chlorophyll content, photosynthetic rate, and stomatal conductance were reduced in the presence of weeds, and intercellular CO2 levels increased. Deeper SWIR light absorption occurred in the weed treatment as expected, accompanied by spectral changes in the visible (VIS) and near infrared (NIR) ranges. The results highlight the potential of using spectral measurements as an indicator of competition for water.
AB - Understanding the spectral characteristics of crops in response to stress caused by weeds is a basic step in improving the precision of agricultural technologies that manage weeds in the field. This research focused on the competition between corn (Zea mays) and redroot pigweed (Amaranthus retroflexus), a common weed that strongly reduces corn yield. The aim of this research was to characterize the physiological changes that occur in corn during early growth because of crop–weed competition and to examine the ability to detect the effect of competition through hyperspectral measurements. A greenhouse experiment was conducted, and corn plants were examined during early growth, with and without weed competition. Hyperspectral measurements were combined with physiological measurements to examine the reflectance and photosynthetic activity of corn. Changes were expected to appear mainly in the short-wave infrared region (SWIR) due to competition for water. Relative water content (RWC), chlorophyll content, photosynthetic rate, and stomatal conductance were reduced in the presence of weeds, and intercellular CO2 levels increased. Deeper SWIR light absorption occurred in the weed treatment as expected, accompanied by spectral changes in the visible (VIS) and near infrared (NIR) ranges. The results highlight the potential of using spectral measurements as an indicator of competition for water.
KW - Crop–weed competition
KW - Hyperspectral indices
KW - Hyperspectral measurements
UR - http://www.scopus.com/inward/record.url?scp=85100377690&partnerID=8YFLogxK
U2 - https://doi.org/10.3390/rs13030513
DO - https://doi.org/10.3390/rs13030513
M3 - Article
SN - 2072-4292
VL - 13
SP - 1
EP - 14
JO - Remote Sensing
JF - Remote Sensing
IS - 3
M1 - 513
ER -