Inter-Genotypic Competition in Soybeans II. Predicted and Observed Performance of Multiline Mixtures1
- C. A. Brim and
- W. M. Schutz2
AH of the 10 possible two- and three-line mixtures of four soybean (Glycine max L. Merrill) lines exceeded the yield of component means. Seven of the mixtures were superior, although not significantly, to the best component of the respective mixtures. Mixtures were seldom more efficient (seed yield per unit of straw) than expected on the basis of component mean performance. The increased productivity was closely associated with the magnitude of net competitive effects. A model which utilized estimates of within- and between-row competition effects for predicting the yield of mixtures was extremely reliable. The sum of the deviations of predicted from observed was essentially zero for the yield of two- and threeline mixtures. This result indicated that the deviations were a result of random error rather than bias in the model. Competitive effects obtained in hill plots appeared to be reliable estimates of within-row competition despite the disparity in plant densities for the two planting configurations. Effects due to between-row competition contributed very little to the agreement between predicted and observed performance. The results suggest that a nine-hill plot is an effective field design for determining pair-wise competitive effects in soybeans, and that it may be useful for determining these effects in other crop species.Please view the pdf by using the Full Text (PDF) link under 'View' to the left.
Copyright © . .