Using airborne video, global positioning system, and geographical information system technologies for detecting and mapping citrus blackfly infestations.
The application of airborne video data with global positioning system and geographical information system technologies is described for detecting infestations of Aleurocanthus woglumi in Citrus orchards in the Lower Rio Grande Valley of Texas. Aphid infestations could be easily detected on colour-infrared and black-and-white near-infrared video imagery. Deposits of sooty mould fungus (Capnodium citri) on the foliage gave them a distinct grey-black image tonal response. Quantitative data obtained from near infrared digitized video images showed that digital values of infested trees were significantly lower than those from uninfested trees. The global positioning system latitude-longitude coordinate data of infested orchards was entered into a geographical information system to map infested orchards over a large agricultural area and develop a digital image data base for future reference.