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CURRENT STATUS AND OPPORTUNITIES FOR THE CONTROL OF 
NEMATODES BY PLANT BREEDING 
August E, Kehr, Crops Research Division, Agricultural Research Service, 
U.S, Department of Agriculture, Plant Industry Station, Beltsville, Md. 
Despite many advances in the control of 
plant-parasitic nematodes by biological or by 
nonbiological methods, the estimated annual 
losses in the United States, based upon actual 
trials on 18 crops, amount to nearly $400 
126 
million (81), The total annual loss for the 78 
common agricultural crops may wellapproach 
$1 billion, Such heavy loss justifies expanded 
research in nematode control by breeding and 
other means, 
