1. Ali El Battay (Dr.) Yap Tsong Shiuan Kamaruzaman SIJAM (Dr.) Mazlan HASHIM (Prof. Dr.)

2. PROACTIVE APPROACH TO USE HYPERSPECTRAL REMOTE SENSING FOR CROP BIOTIC STRESS DETECTION  “proactive” means controlling a situation by causing something to happen rather than waiting to respond to it after it happens. RS data are the mirror of what happened on Earth surface.  Using PRS, the change detected in RS data are deliberately induced and the Earth surface is intentionally modified in such a way that the electromagnetic signal reflects new information inaccessible by conventional RS techniques.

3.  Early detection and treatment of cash crop diseases can prevent unnecessary losses and significantly increase crop yield  The induced spectral response will aid in early detection of cash crop diseases through synchronization of remote sensing data acquisition with the routine farming practices and/or environmental fluctuations

4. CONVENTIONAL METHODS  Visual Approach  Requires years of knowledge and experience  Time consuming  Labour intensive  Difference in perception among individuals REMOTE SENSING  Thermology  Detect transpiration  Passive  Sensitive to environment  Chlorophyll fluorescence imaging  Chlorophyll efficiency  Artificial illumination  Reflectance imaging  Satellite or airborne platform  Expensive

5.  To prove the occurrence of pre-symptom stage (spectral) of ralstonia solanacearum infection in cucumber plant  To determine the possibility of inducing a measurable spectral change by using nutrient, light exposure and water stress during the pre-symptom stage

6.  Crop Type: Cucumber (Cucumis sativus L.)  Pathogen: Ralstonia solanacearum (Bacterial Wilt)  Stimuli: Nutrient content, water content, light exposure

7.  Cucumber (Cucumis Sativus L.) is one of the most widely produced vegetable in the world.  An annual, creeping herb, up to 5 m long  It is grown for the immature fruits which are used as a salad vegetable, pickles and sometimes boiled in stews Sowing Week 0 Germi- nation Week 1 Trans- plantin g Week 3 Flower- ing Week 6 Harvest Week 8-10

8.  A gram-negative, plant pathogenic, soil bacterium  The cause of bacterial wilt in a very wide range of potential host plants  Common crop hosts are: potatoes, tomatoes, aubergine, banana, geranium, ginger, tobacco, sweet peppers, olive, etc.  Transmission is through contaminated: tools, machinery, handlers, water, soil and seed

9.  Severe rapid wilting of leaves  Chlorotic or stunted with adventitious roots on the stem  Glistening beads of dark gray slimy ooze from the infected xylem in stem cross sections  Bacterial streaming of fine, milky white strands from xylem vessels occurs when stems are cut and placed in water

11. Non-inoculated cucumber under normal optimal conditions Inoculated cucumber under normal condition Non-inoculated cucumber + manipulated nutrient Inoculated cucumber + manipulated nutrient Non-inoculated cucumber + manipulated light exposure Inoculated cucumber + manipulated light exposure Non-inoculated cucumber + manipulated water content Inoculated cucumber + manipulated water content Spectroradiometer measurement Determination of pre-symptom stage of ralstonia solanacearum in cucumber Quantitative estimation using vegetation indices Detection of spectral signature changes in the pre- symptom stage

12. Normal Condition Nutrient Stress Water Stress Non-inoculated Seed Light Stress Backup Inoculated Seed Normal Condition Nutrient Stress Water Stress Light Stress Backup

15. (a)ASD FieldSpecPro Spectroradiometer connected to the Panasonic Toughbook. (b) Fiberoptic attached to pistol grip with 8˚ foreoptic.

17.  White reference  Dark current  Raw DN (10 times)  Constant lighting  Constant angle  Accompanying image and notes θ

18. Normalised Difference Vegetation Index Most widely used vegetation index. Difference between the high chlorophyll absorption and the reflection of leaf cellular structure Structure Insensitive Pigment Index Estimate the ratio of carotenoids to chlorophyll-a. Triangular Vegetation Index Total area of triangle formed by green, red and infra-red bands gives information on chlorophyll absorption and leaf tissue abundance Nitrogen Reflectance Index Estimate nitrogen content in the target which is related to the chlorophyll-a content. Modified Chlorophyll Absorption Ratio Index Measures the chlorophyll absorption (670 nm) relative to the green reflectance peak (550 nm) and infrared reflectance (700nm)

25.  To prove the occurrence of pre-symptom stage (spectral) of ralstonia solanacearum infection in cucumber plant  To determine the possibility of inducing a measurable spectral change by using nutrient, light exposure and water stress during the pre-symptom stage

33. Inoculated Non-inoculated Normal Condition Light StressWater Stress Nutrient Stress

34.  The occurrence of pre-symptom spectral stage of ralstonia solanacearum infection in cucumber plant has been proven, and last at least 10 days in this experimental conditions.  There is a possibility of inducing a measurable spectral change by reducing light exposure (- 5 hours) during the spectral pre-symptom stage. MCARI and NRI vegetation indices respond to this induced EM-Spectral change.

35.  Understanding!  Modeling and Generalization!  Implementation feasibility? .  Monetising!

36. Questions?