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1Department of Agronomy, University of Illinois, Urbana, Ill.
2Crops Research Division, Agricultural Research Service, U. S. Department of Agriculture, Urbana, Ill.
1
Received June 15, 1959.
2
This work was supported in part by grants from NCM-23 Regional Funds, U. S. Department of Agriculture, and the University Research Board, University of Illinois.
3
Publication No. 331 of the U.S. Regional Soybean Laboratory, Urbana, I11.