VIEW ARTICLE

Evidence of Pectinase Activity Between Cronartium ribicola and Pinus monticola. Bruce L. Welch, Biological Laboratory Technician, U.S. Department of Agriculture, Forest Service, Intermountain Forest and Range Experiment Station, Ogden, Utah 84401, stationed at Logan, Utah, and Moscow, Idaho; Neil E. Martin, Plant Pathologist, U.S. Department of Agriculture, Forest Service, Intermountain Forest and Range Experiment Station, Ogden, Utah 84401, stationed at Logan, Utah, and Moscow, Idaho. Phytopathology 64:1287-1289. Accepted for publication 30 April 1974. DOI: 10.1094/Phyto-64-1287.

This report contains the first in vivo evidence of pectinase activity during the pathogenesis of a rust disease. Comparisons between noninfected bark of Pinus monticola, and bark infected by Cronartium ribicola, show a significant decrease (44%) in the amount of extractable pectic substances from infected bark. Data are provided that indicate significant increases in infected bark of materials soluble in petroleum ether and in 95% ethanol.