Open AccessDetection of Rice Panicle Blast with Multispectral Radiometer and the Potential of Using Airborne Multispectral Scanners
Author(s) -
Takashi Kobayashi,
Eiji Kanda,
Katsuki Kitada,
K. Ishiguro,
Yoichi Torigoe
Publication year - 2001
Publication title -
phytopathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.264
H-Index - 131
eISSN - 1943-7684
pISSN - 0031-949X
DOI - 10.1094/phyto.2001.91.3.316
Subject(s) - panicle , multispectral image , reflectivity , remote sensing , biology , stage (stratigraphy) , near infrared spectroscopy , horticulture , agronomy , veterinary medicine , optics , medicine , geology , physics , paleontology , neuroscience
Rice reflectance was measured to determine the spectral regions most sensitive to panicle blast infection. Reflectance increased in the 430- to 530-, 580- to 680-, and 1,480- to 2,000-nm regions at the dough stage both in the laboratory and the field as the percentage of diseased spikelets increased. The wavebands of the greatest sensitivity were in the visible region, located near 485 and 675 nm. After the yellow-ripe growth stage, near-infrared rather than visible reflectance responded to panicle blast infections. Ratios of rice reflectance were evaluated as indicators of panicle blast. R470/R570 (reflectance at 470 nm divided by reflectance at 570 nm), R520/R675, and R570/R675 decreased significantly as the incidence of panicle blast increased at the dough stage. At the yellow-ripe stage, R550/R970 and R725/R900 were used to estimate panicle blast severity as measured in terms of the percentage of diseased spikelets. According to the simulation that uses ground-based sensor data, airborne multispectral scanners may be effective in detecting the occurrence of panicle blast using a band combination of 530- to 570- and 650- to 700-nm regions at the dough stage.