Phenotypic diversity among maize landraces is obvious in kernel color, ear and kernel shape and size, and agronomic traits such as plant height and length of the growing cycle. Traditionally, this phenotypic diversity has been used to classify populations into “races.” Currently, 59 races of maize have been described in Mexico. According to DNA analyses, these races are organized as a continuum and their differentiation is mainly due to isolation by distance. Recent genetic studies of landraces in Oaxaca (Mexico) have shown that gene flow between maize populations is quantitatively important but that management of seed by farmers maintains strong agromorphological differentiation between maize populations. |
Download document