For our discussion, the most notable difference is that the maize cob is solid, whereas the teosinte cob is brittle and comes apart at maturity. Maize does not disperse itself and therefore does not exist as a free species in nature. Recently, some biotechnology companies have requested authorization to plant and market transgenic maize in Mexico. Several ecological groups have raised concerns about the potential risks of introducing such plants to Mexico, where maize originated.
Arguments stating that maize is genetically fragile are weak.
It seems paradoxical to argue that it is necessary to protect the genetic background of corn when, for 6000 years of traditional breeding, Martinez-Soriano says we have protected only alleles important for humankind. Even if we decide to protect the actual genotypes, there should be no need for concern. Any transgene transferred inadvertently to native maizes can be removed from the progeny by selecting against the incorporated trait. Maize is always under strong artificial selection, and therefore natural selection has no practical meaning for the species. On the other hand, transgenes cannot be established in a natural population of teosintes.