Mustafa Mirik, MMirik@ag.tamu.edu1, Gerald J. Michels, g-michels@ag.tamu.edu1, Norman C. Elliott, norman.elliott@ars.usda.gov2, Robert Bowling, r-bowling@tamu.edu3, Sabina Kassymzhanova-Mirik, SKassymzhanova@ag.tamu.edu1, and Vasile Catana, Vasile.Catana@okstate.edu2. (1) Texas A&M University, Agricultural Experiment Station, Entomology, 2301 Experiment Station Road, Bushland, TX, (2) USDA-ARS, PSWCRL, Stillwater, OK, (3) Texas Cooperative Extension, Pest Management - Entomology, 310 E. 1st Street, Dumas, TX
Abstract: Remote sensing techniques have the potential to provide information about vegetation characteristics. Therefore, this study was designed to determine the ability of a hyperspectral field spectrometer along with a digital camera to estimate greenbug, Schizaphis graminum (Rondani), damage to wheat, Triticum aestivum L., in field condition. Percentage reflectance data and digital images were collected over 1 m2 wheat plots in four fields in mid-May of 2005. Percentage reflectance data were transformed into spectral vegetation indices and a damage quantification software package was used to determine percentage damage in each of the digital images. The percentage damage was also visually assessed on the ground. A simple linear regression procedure was conducted to investigate the relationships between spectral vegetation indices and percentage damage obtained from the ground and digital images. The results show that there were strong relationships between percentage damage and Spectral Index Two (SI2). The coefficients of determination were 0.69, 0.88, 0.93, and 0.96 for the percentage damage determined using the digital images and SI2 for fields 1-4, respectively. The relationships between the percentage damage collected on the ground and SI2 were 75%, 81%, 87%, and 93% for the fields 1-4, respectively. These results strongly suggest that percentage reflectance and digital image data can be used to estimate greenbug damage in wheat in field conditions with a high degree of accuracy and precision.
Species 1: Hemiptera Aphididae
Schizaphis graminum (Greenbug)
Keywords: Remote Sensing, Vegetation Indices
Recorded presentation