The Plant Pathology Internet Guidebook
A powerful collection of pathology pages all over the web.

Plant Viruses Online
Information on nomenclature, host range, taxonomy and detection methods of numerous plant viruses.

APSnet
The website of the American Phytopathological Society (APS), an international scientific organization devoted to the study of plant diseases and their control.

EPPO
The European Plant Protection Organisation.

NRSP5
National Research Support Project 5, supporting research and development of virus-free pome and stone fruit trees.

International Society for Horticultural Science
The leading worldwide organization of horticultural scientists with contacts all over the world.

Bioreba
Commercial producer of pathogen test kits

Agdia
Easy-to-use test kits, reagents and laboratory testing services for agricultural diagnostics.

Animal and Plant Health Inspection Service
Extensive information on animal and plant health/disease topics, USDA regulations, control of invasive species, agricultural chemicals, and related public health.

Plum Pox Virus Symptoms Booklet
The purpose of this guide is to assist stone fruit growers to identify Plum Pox Virus and differentiate it from other disease symptoms.