Growing Maize for Genetic Studies

Abstract

CORN is a large kerneled, highly domesticated, vigorous annual plant of tropical origin. Because it is a natural cross-pollinator it is highly heterogeneous and responsive to selection pressure. Corn has been taken by humans into all but the harshest of agricultural environments. Strains of corn are known that grow as far north as southern Canada while others range to the extremes of the tropical forest and desert oasis. Some grow at sea level and others at 11,000 feet of elevation. Those lines and strains most used for breeding and genetic purposes are much more restricted in adaptation and therefore require narrower limits on growth conditions in order to produce a useful crop. There is no doubt that strains could be found or developed that would be satisfactory for use under most plant growing conditions. For the purpose of this chapter the conditions of choice will be described while keeping in mind that, by proper manipulation and by appropriate choice of strains, there is considerable flexibility in the conditions leading to a successful corn crop.