Towards Model-Assisted Evaluation of Perennial Ryegrass Varieties

Abstract

As in other crops, evaluation of grass genotypes requires objective measures of the performance of individual plants or swards. However, because of genotype-by-environment-by-management interactions, the genetic value of a genotype cannot always be easily assessed. Detailed ecophysiological models that describe physiological processes determining phenotypic traits consist of parameters that can be considered as genetic coefficients that better represent the genetic value of the genotype. We used the LINGRA grass model to estimate model parameters for a perennial ryegrass variety based on harvest data from seven growing seasons. Despite its relative simplicity, the LINGRA model succeeded in simulating the dry matter harvest of different years, although it substantially underestimated the yield in the driest year. The grass-specific LINGRA features should therefore be combined with a more extensive ecophysiological model to enable reliable estimation of genotype specific parameters.