Heterosis and heterotic patterns among maize landraces for forage
Lopez Cesar Gabriel; Bertoia Luis Maximo and Burak Ruggero
Abstract: Corn silage is a high-quality forage crop used in many areas of the world. Although vegetative and reproductive components of the plant must be considered, breeding programs in temperate regions are mainly based on the Reid x Lancaster heterotic pattern that has undergone several cycles of improvement for grain yield. Moreover, hybrids selected for forage production are early maturing genotypes not adapted to warm-temperate or subtropical areas. Consequently, exotic germplasm should be considered as a source of materials for breeding programs. Eight landraces were crossed following a diallel mating design. Interpopulation crosses showed high heterosis for ear, stover, and whole plant dry matter yield (EY, SY, and WY, respectively). On average, crosses had higher SY than checks, but lower EY. Considering WY, two interpopulation crosses had higher means than all commercial checks, indicating the potential of the germplasm evaluated. Two composites were selected and different breeding strategies are discussed.