Use of Geographic Information Systems and Remote Sensing in Integrated pest Management Programs

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1 Use of Geographic Information Systems and Remote Sensing in Integrated pest Management Programs Teresia Nyoike, Post-doctoral Research Associate Entomology and Nematology Dept. University of Florida

2 Integrated Pest Management (IPM) It is a knowledge intensive frequent sampling use of thresholds Recognizes that insect pests are not uniformly distributed in the field Most insect and mite populations are known to occur in hot spots in the field However, management actions are still based on whole field treatment Alternative is to use site-specific pest management

3 Site-specific pest management (SSPM) SSPM approach recognizes that pest populations are varied in time and space Therefore: more informed management decisions more efficient use of inputs (chemical, biocontrol agents) conserve the environment Involves developing sampling program to generate pest density maps that will guide management to target specific locations To develop the maps, a global positioning systems (GPS), geographic information systems (GIS) and geostatistics are used

4 Example: Distribution of spider mites and its predatory mite TSSM populations are known to occur in hot spots in the field Temporal and spatial variability of TSSM & its predator (N. californicus): provide valuable information towards mite management study their population dynamics determine how predatory mites disperse from a point of release after inoculation

5 Sampling and generating pest density maps - GPS/GIS Decide your sampling design regular/stratified/transect Georefencing your sampling points Input your geo-referenced points into GIS (e.g. ArcMAP ESRI) Keep a record of the insect data and geo-referenced points -GPS point 1 corresponds to insect population at that exact point 1 Choose the optimum interpolation method to generate the continuous surfaces (maps)

6 Use of maps in making management decisions Mite infestation in the field

7 Sampling dates: Map 1 March 1 st Map 2 - March 14 th Map 3 March 30 th TSSM management on March 1 st could be done only in the center and north side of the field Delaying until March 30 th will require treating the whole field

8 Density maps showing distribution of spider mites and N. californicus

9 GIS Where? - location What is the trends? - what happened Patterns? what if? - modeling (pest data + weather factors or soil type etc)

10 Use of Remote Sensing for Improved Sampling Techniques Use of leaf reflectance spectroscopy (remote sensing) to detect pest damage on leaves

11 Use of Remote Sensing for Improved Sampling Techniques Sampling and monitoring are key steps for timely pest management However, it is time consuming and labor intensive e.g. sampling programs for spider mites involve the use of hand lens or visual observations for symptoms in the field There is a need to develop a different approach to enhance or supplement sampling techniques The potential for using remote sensing has been demonstrated in pest management for detection of pests injury TSSM > 1mm

12 Leaf Reflectance Spectroscopy Healthy leaf reflectance is low in the visible region ( nm) due to strong absorption of EMR by chlorophyll Image credits: innovative gis.com NIR region ( nm) reflectance is high due to light scattering by the internal plant cells Plant stress due to insect pests & diseases cause changes in reflectance in the VIS & NIR regions due to changes in chlorophyll content and cellular damage

13 Example: Spider mites Mites injury removal of chlorophyll cell structure damage through their feeding This causes changes in leaf reflectance properties of the leaf These are changes can be quantified to indirectly estimate the number of spider mites causing injury on the leaf

14 Reflectance (%) Leaf Reflectance Curves 70 Control Low High Wavelength (nm) Control ± 1.5 Low ± 12.8 High ± 37.6 NIR region was the most important region predict TSSM injury

15 Equipment used Equipment that can be used to collect spectral reflectance data in the VIS/NIR regions ( nm) Spectroradiometer Cary 500 Scan UV-Vis-NIR Spectrophotometer

16 Remote sensing platforms Satellites Landsat, GeoEye Inc, Quickbird Air craft

17 Field Applications In real-time sampling programs pests Hand-held spectrophotometers can be mounted on a tractor with a GPS to generate field maps for sitespecific pest management of pest Ground-based

18 Spotted Wing Drosophila in the U.S. Since 1980