MATERIALS AND METHODS
Plant Materials: The study was conducted at the
International Institute of Tropical Agriculture (IITA),
Ibadan (7°26’N, 3°54’E) a transition zone between humid
and sub-humid tropics. A total of 24 genotypes, including
both landraces and elite genotypes, were provided by
IITA for this study. The names and source of these
genotypes are described in Table 1. About 200 to 250 mg
fresh and young leaves sample were collected, frozen in
liquid nitrogen and stored at -80°C until use for DNA
extraction. In total 24 genotypes were analyzed