1. Institute of Biophysics, Academy of Sciences of the Czech Republic, Kralovopolska 135, CZ - 612 65 Brno, Czech Republic, Deparment of Chemistry and Biochemistry, Mendel University of Agriculture and Forestry, Zemedelska 1, 613 00 Brno Czech Republic, Grain Marketing and Production Research Center, Agricultural Research Service, U.S. Department of Agriculture, Manhattan, Kansas 66502, and ProdiGene, Inc., 101 Gateway Boulevard, College Station, Texas 77845