Geographic information systems and geostatistics in the design and validation of regional plant virus management programs

A regional management plan was designed and implemented for a multivirus, multivector, disease complex in tomatoes in the Del Fuerte Valley, Sinaloa, Mexico. The viruses include tobacco etch and cucumber mosaic with aphid vectors, a geminivirus complex with whitefly vectors, tomato spotted wilt with thrips vectors, and tomato mosaic with no known vector. Although the viruses and their vectors are biologically diverse, all are transmitted by flying insects, with the exception of tomato mosaic, and all except tomato mosaic are known to have alternate hosts among weeds and other crop plants in the area. Because of these similarities, we developed a risk-assessment process based on general virus infection hazards rather than specific viruses