The GGE biplot from the SREG model was constructed according to the manual and SAS
program available at the web page of CIMMYT in Biometrics and Statistic Unit (BSU) or at
http://www.cimmyt.org/english/wps/biometrics/. Following Burgueño et al. (2009), Yan et al.
(2001) and Yan and Hunt (2002), a brief description and interpretation of the GGE biplot is
presented below: