VIEW ARTICLE

Levels of Chlorogenic Acid in Tobacco Cultivars, Healthy and Infected with Thielaviopsis basicola. S. K. Gayed, Plant Pathologist, Agriculture Canada, Research Station, Delhi, Ontario, Canada N4B 2W9; Nestor Rosa, Plant Physiologist, Agriculture Canada, Research Station, Delhi, Ontario, Canada N4B 2W9. Phytopathology 65:1049-1053. Accepted for publication 11 April 1975. DOI: 10.1094/Phyto-65-1049.

In 3- and 4-week-old tobacco seedlings higher levels of chlorogenic acid (CA) were recovered from the immune cultivar Burley 49 than from the susceptible White Mammoth and the tolerant cultivars Hicks Broadleaf and Delhi 34. At the 5-, 6-, and 7-week-old stages, CA was higher in both root and leaf of Burley 49 compared to White Mammoth. At these stages, CA content of the roots of all cultivars was 20 to 25 times higher than that of the leaf. Infection of tobacco by Thielaviopsis basicola, either under controlled greenhouse conditions or in the field, resulted in the accumulation of CA not only in the root but also in the leaf. CA accumulation increased with the increase of tolerance to black root rot. The significance of such increase as a possible defensive mechanism is discussed.