Detection of a Tristeza-Seedling Yellows Strain in Spain

Abstract

In late 1984, some growers were found to be using budwood of a very early maturing satsuma mandarin of uncertain origin, for topworking citrus orchards near Valencia. Indexing of this material showed that it was infected with a very severe strain of citrus tristeza virus (CTV). It induced severe stunting, stem pitting, vein clearing and vein corking in Mexican lime and C. macrophylla; conspicuous stunting and seedling-yellows on Eureka lemon and Duncan grapefruit and stem pitting on sweet orange, grapefruit arid rough lemon. None of the common CTV strains previously studied in Spain induces these severe symptoms. There is some evidence indicating that the original satsuma was illegally introduced from Japan. A program has been established for the eradication of this CTV strain.