TREATMENT OF CEREAL SEEDS BY DRY HEAT 



By D. Atanasoff, Assistant in Plant Pathology, University of Wisconsin, and A. G. 

 Johnson, Pathologist, Office of Cereal Investigations, Bureau of Plant Industry, 

 United States Department of Agriculture, and Associate Professor of Plant Pathology, 

 University of Wisconsin 



INTRODUCTION 



In the investigation of possible control measures for certain seed- 

 borne diseases of cereals which do not yield to the ordinary chemical and 

 hot water seed treatments, the authors found dry heat to be particularly 

 adaptable. The progress made with these seed treatments seems to 

 warrant the publication of this preliminary paper, giving a brief review 

 of the pertinent literature, as well as the methods employed and the 

 results obtained by the writers to date. 



REVIEW OF THE LITERATURE 



The early literature, as well as some of the more recent papers relative 

 to heat treatments, represents chiefly the results obtained by plant 

 physiologists who were studying the effect of high temperatures and 

 drying on germinability of various seeds, including those of certain cereals. 



Edwards and Colin (9),^ in 1834, were the first to make important 

 contributions on the subject. 



Heiden (14, p. 30-J7), in 1859, showed that barley germinated after 

 being exposed for one hour to dry air at 90° C, while similar grains heated 

 in water at 60° C. for the same period of time were killed. 



Sachs (24), in 1865, showed that moistened seeds of rye, barley, corn, 

 peas, and flax were killed at from 50° to 60° C, while those containing less 

 moisture withstood 70° C. Length of exposure was not mentioned. 



Just (77, 18), in 1875 and 1877, found that clover and other kinds of 

 seeds heated in a saturated atmosphere at 50° C. for 48 hours, or at 75° C. 

 for I hour, lost their viability, while similar seeds endured a dry heat of 

 120° C. for I hour. 



Von Hohnel (75), in i877,working with the seeds of various plants, 

 reported that most of them when dry were able to endure exposure to 

 110° C. for 60 minutes and that some were found viable even when ex- 

 posed to 125° C. for 15 minutes. 



' Reference is made by number (italic), to " I^iterature cited," p. 388-390. 



Journal of Agricultural Research, rl .1 ; Vol. XVIII, No. 7 



Washington, D. C. , Jan. 3, 1920 



te " (379) Key Xo. Wis.-i7 



