Testing the Assumption of Constant Relative Yield Total in Replacement Series Experiments

Abstract

The Relative Crowding Coefficient (RCC) is a common measure of interspecific competition in a replacement series experiment. However, the interpretation of RCC depends upon the validity of an assumed functional relationship in total species yield. We develop inference procedures based upon the Relative Yield Total (RY T ), a function of species yields in mixture and monoculture plantings, that may be utilized to assess the plausibility of the species yield functional form under which RCC is a reasonable metric of interspecific competition. The performance of the proposed RYT inference procedures is evaluated on the basis of a simulation study. Using the proposed methodology, we conduct RYT inference in a replacement series experiment of bahiagrass (Paspalum notatum) and smutgrass (Sporobolus indicus).