Yield and Maturity of Populations of Drilled Corn Hybrids on the Northern Great Plains

The majority of corn population studies have been conducted in the eastern or central area of the corn belt, where moisture is not usually a limiting factor. It would be unusual if those studies would apply to corn growing in the western regions of the corn belt, where moisture is often inadequate. Therefore a study dealing with rates of planting in the western regions of the corn belt is of major interest. Every spring the corn growers of this area are confronted with a great deal of literature indicating the need for high plant populations to realize maximum yield. A study dealing with plant populations would help the corn growers of this are decide which planting rate is best suited for their growing conditions, regardless of the advantage to the seed corn companies. This study was undertaken to extend the range of available information on population levels best suited to conditions found in the western edge of the corn bel. Using populations ranging from very low to very high, it was hoped to establish the general nature of the yield-stand curve. This is one part of a series of genotype-environment interaction studies in corn and small grain presently being conducted at South Dakota State College. These are designed to test the hypothesis that a general population-production curve can be worked out for each crop. The general curve could then be modified for conditions such as moisture, hybrids, locations, length of growing season and fertility levels. The present work also fits into the continuous exploration of the place of corn and available corn genotypes in the agriculture of this area