The analysis of yield-density relationships in binary mixtures using inverse polynomials

Abstract

SUMMARY: The reciprocal relationship commonly used in the analysis of plant yield-density relationships in monoculture is extended to allow a similar treatment of binary mixtures, using the model:w^–1_a = A_a × B_aap_a × B_abp_bwhere w_a is the plant weight of component a in mixture with component b, and p_a and p_b are the plant densities of a and b respectively. The model gives a good fit to fresh weights taken from a glasshouse experiment involving monocultures and mixtures of red clover (T. pratense L.) and Italian ryegrass (L. multiflorum L.) in different proportions, all grown at a range of plant densities. The interpretive and predictive uses of the model are discussed.