Fig. 2. GGE biplot based on the yield data of 28 soybean genotypes that were tested all three years from 1997–1999. (A) The genotype by environment biplot taking each year-site combination as a single environment; (B) the genotype by site biplot on the basis of data averaged over years. The names of the test sites are in lowercase letters and the names of the genotypes in uppercase letters. EXET = Exeter, STPA = St. Pauls, WINC = Winchester, and WDST = Woodstock.