Introductory

Abstract

Virus diseases of plants, although of course not recognized as such, were known long before the discovery of bacteria. The first record in the literature of which we have knowledge is a description published in 1576 by Charles L’ Ecluse, or Carolus Clusius of a variegation in the colour of tulips, which is now called a ‘colour-break’ and is recognized to be due to an aphid-transmitted virus of the mosaic type. ‘Broken’ tulips are figured in Theatrum Florae published in 1662; these illustrations have been identified as the work of the painter Daniel Rabel. A somewhat later account published in Traité des Tulips, about 1670, contains the first suggestion that the variegation in the flower colour might be due to a disease. In 1715, an account of an infectious chlorosis of Jasminum was published in the Art of Gardening.