VIEW ARTICLE

Fusiform Rust Gall Formation and Cellulose, Lignin, and Other Wood Constituents of Loblolly Pine. S. J. Rowan, Plant Pathologist, Southeastern Forest Experiment Station, Forest Service, USDA, Athens, Georgia 30601. Phytopathology 60:1216-1220. Accepted for publication 18 March 1970. DOI: 10.1094/Phyto-60-1216.

The stem wood of loblolly pine infected with Cronartium fusiforme was compared with that of noninfected loblolly pine. Gall wood was found to have its greatest sp gr near the point where the diam of the gall is largest (the site where the infection probably originated). This increase in sp gr is caused by an accumulation of substances extractable in neutral solvents. Holocellulose and alpha-, beta-, and gamma-cellulose (cell wall constituents) are reduced in gall wood, but lignin content is higher. Gall wood resembles conifer summerwood in lignin content and in the monosaccharide composition of holocellulose. These and other modifications caused by C. fusiforme infection of pine stems are discussed, along with their possible relation to gall formation.