III.2 Control of microorganisms infesting seeds used for laboratory studies.
C.F Konzak, Department of Agronomy and Soils and Program in Genetics, Washington State University, Pullman, Washington, 99163, U S A
After many years of tests and searching for a suitable material to control infestation of seeds used for laboratory seedling tests, we have now found a material through the kind cooperation of Dr. R.F. Line which seems to be the answer. Without reviewing details about the materials that failed us for one reason or another we have found that the product Pentachloronitro-Benzene (PCNB) commercially known as Terrachlor is wholly satisfactory for our purpose. Evidently treated seeds should not be stored for long periods since some damage has been reported from use of a related compound, Terracote. Generally we use it by making a thick water slurry to dip seeds into it, using tweezers as we plant them in our germination blotter "sandwiches" in order to avoid human contact with the material, since it has been reported to be a teratogen. However, larger samples can be treated by shaking seeds in a small amount of slurry. Importantly, it appears not to be harmful to use a considerable excess of the material on the seeds, and thereby assure complete control of microorganisms.