Development of a National Expert System for Diagnosis of Grape Problems
Version 1.0 of the diagnosis expert system has been developed with a database containing information on 161 grape problems including 55 arthropods, 48 pathogenic diseases, 25 phytotoxicity problems, 13 nutritional disorders, 9 abiotic stress disorders, 6 wildlife damage, and 5 physiological disorders. Additional problems will be entered into the database in 2007. The system is currently undergoing debugging and refinement prior to evaluation by a test panel. Production of graphics was initiated in 2006 and draft images have been completed for all first-level menu items.
The diagnosis system uses a symptom-based approach that guides the user through a series of directed questions leading to a ranked list of the most probable problems. The user answers questions based on their observations of symptoms and signs of the problem. Questions are organized in hierarchal levels, enabling the software to analyze responses and select the next level of questions on-the-fly based on the previous responses. This approach streamlines the diagnosis process by focusing on discriminating questions and avoiding extraneous ones.
Each vineyard problem is characterized with diagnostic keywords and a Problem Profile. The system uses the keywords to conduct a sorting routine to identify and display a probability-ranked list of possible problems. The Problem Profile contains text and photographs to assist with diagnosis of the problem.
A database was created to hold Diagnostic Keywords and Problem Profiles for known grape problems caused by pathogens, arthropods, vertebrate and other pests, abiotic stresses, nutritional disorders, chemical phytotoxicity, and physiological disorders. Database entries were created based on the personal experience of the principal investigators and from several standard references including the Compendium of Grape Diseases, 1988 APS Press and Grape Pest Management, 1992, University of California, Division of Agriculture and Natural Resources.
The technical accuracy of database entries will be validated by an editorial review process involving experts from around the U.S. Participation in the project by experts will be facilitated by the previous creation of draft versions of Diagnostic Keywords and Problem Profiles, which will minimize the time commitment of reviewers. Experts will be requested to review and edit selected problems. Reviewers will begin testing version 1.0 of the Expert System in 2007 and will be provided password-protected access to the Problem Profile Editor database interface. Reviewers will be credited for their work and will be invited to contribute new problems based on their experience. High-quality photos of symptoms and signs will also be solicited from experts and photo credits acknowledged. The diagnosis expert system will be validated through test use of version 1.0 and 2.0 by a panel comprised of vineyard managers, Extension educators, and students.