Intergenotypic competition studies in corn (Zea mays L.) : I. Among experimental hybrids

Four experimental single-cross hybrids were evaluated for intergenotypic competition in a split-plot design with 7 replicates and a stand density of 51,700 plants/hectar in 1970, 1971 and 1972 at Lincoln, Nebraska. The arrangement of rows used in this study allowed the measurement of effects of different levels of competition on the traits grain yield, plant height and a selection index. There were some definite inter-genotypic competitive effects for all three traits among the pairs of hybrids studied. Variation in types of intergenotypic interaction was found.A two-step process was suggested to take advantage of favorable competitive interactions for increasing grain yield.Failure of mixtures in corn to take advantage of favorable competitive situations was discussed.