The Studies on Citrus Virus and Virus-Like Diseases and Their Speed Indexing Technique

The virus and virus-like diseases of citrus trees had become seriously epidemic since the first outbreak of Likubin (greening) in 1951, and called public attention in citrus industry of Taiwan. The etiological studies on the systemic virus and virus-like diseases of citus trees have been made through transmission experiments with the diseased scions and vector insects. Citrus trees of the all commercial cultivars grown on the island were proved to be commonly infected by the virus and fastidious bacteria pathogens. In order to promote the pathogen-free foufldation stock and budling program for controlling the systemic diseases of citrus trees, the identification of causal viruses, their pathological studies and development of disease-indexing techniques were realized to be primarily important. The etiolngical natures and diagnostic technology of the citrus virus and virus-like diseases were briefly described