dosage at the proper time and byaproved technique. In the development of chemical weed 
control practices the behavior and persistence of herbicides in soils must be understood 
to avoid possible injury to the crop plants being treated as well as succeeding crops in 
the rotation. One of the largest gaps in knowledge is possibly the effects of the chemicals 
on soil microorganisms, and the specific role that soil microorganisms play in the 
degradation of pesticides. 
Future progress in the development and use of pesticides will depend upon co- 
operative basic research of scientists in public agencies and in the chemical industry. 
The continuation and expansion of basic research is the forward look and this holds the 
secret of successful development and use of crop-protecting chemicals in the future. 
LITERATURE CITED 
(1) Diamond, A. E., and Horsfall, J. G. 
1955. Fifty years of fungicides. Ann. Appl. Biol. 42: 282-287. 
(2) Dunegan, John C., and Doolittle, S. P. 
1953. Plant diseases. U.S. Dept. Agr. Yearbook 1953: 115-120. 
(3) Horsfall, James G. 
1956. Principles of fungicidal action. Chronica Botanica Co. 
Waltham, Massachusetts. 279 pp. 
(4) Large, E.C. 
1940. Advance of the fungi. Henry Holt and Co., 488 pp., illus. New York. 
(5) McNew, George L. 
1959. Landmarks during a century of progress in use of chemicals to control 
plant diseases. Plant Pathology - Problems and Progress 1908-1959. The 
University of Wisconsin Press, Madison. 588 pp. 
(6) Taylor, A. L. 
1951. Chemical treatment of the soil for nematode control. Adv. in Agron. 3: 
243-264. 
(7) ——_——_ 
1959. Progress in chemical control of nematodes. Plant Pathology - Problems and 
Progress 1908-1958. The University of Wisconsin Press, Madison. 588pp. 
(8) Taylor, A. L., and McBeth, C. W. 
1941. A practical method of using methyl bromide as a nematocide in the field. 
Proc. Helminthol. Soc., Washington, D.C. 8: 26-28. 
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