|
Vegetation indices as indicators of damage by the sunn pest
(Hemiptera: Scutelleridae) to field grown wheat
H. Genc1*,
L. Genc 2, H. Turhan3,
S. E. Smith4 and J. L. Nation5
1Department
of Plant Protection,
Agricultural Faculty, Canakkale Onsekiz Mart University,
17020 Canakkale, Turkey.
2Agricultural
Data Processing and Remote Sensing Laboratory, Department
of Agricultural Engineering, Agricultural Faculty, Canakkale
Onsekiz Mart University, 17020 Canakkale, Turkey.
3Department
of Field Crops, Agricultural Faculty, Canakkale Onsekiz Mart
University, 17020 Canakkale, Turkey.
4Department
of Geomatics, School of Forest Resources and Conservation,
University of Florida, Gainesville, Florida USA 32611.
5Department
of Entomology and Nematology, University of Florida,
Gainesville, Florida USA 32611.
*Corresponding author. E-mail:
genchanife@hotmail.com.
Fax:
90-0 286 218 0545.
Accepted 4 January, 2008 |
|
The sunn pest, Eurygaster integriceps Put.
(Hemiptera: Scutelleridae), also known as sting or cereal
pest, is one of the most economically important pests of
wheat in the world. In this study, a collapsible nylon cloth
cage experiments were conducted to determine the feasibility
of using remote sensing techniques to detect stress in wheat
caused by the density of sunn pests. The results show we can
detect the amount of stress in wheat caused by different
life stages of sunn pest with a hand-held radiometer.
Normalized difference vegetation index (NDVI) based indices;
NDVIsg, NDVId, NDVIr, and structure insensitive pigment
index (SIPI) were chosen out of 19 indices initially tested.
The NDVI based vegetation indices derived from hyperspectral
data, recorded by a hand held spectroradiometer, were used
to determine the predicted indices using the initial number
of Sunn Pest (NOSP). Overall, r2 values of all
predicted indices calculated for 3rd instars were
lower than those of 4th and adult stage. When r2
was considered separately, predicted NDVIr index value
(87.4) was the highest and predicted SIPI index value is
lowest (80.7) in 3rd instars. The highest r2
value was obtained in adult stage of sunn pest is
NDVIsg (96.9) compare with NDVId (95.5), NDVIr (92.4) and
SIPI (94.2). It was also concluded that remote sensing could
detect not only the different stages pest damage on wheat,
but also the number of sunn pest stages density affect in
controlled experiments.
Key words:
Remote sensing, Eurygaster integriceps, insect
damage, NDVI, spectroradiometre. |
