An evaluation of differential susceptibility of barley varieties to lodging under varying environmental conditions

Abstract

Information on the variation in susceptibility to lodging between barley varieties under different environments can be used for local prediction. It can also be used to identify varieties that are robust to environmental variation. Efficient methods to obtain analogous information on the local yielding capacity of crop varieties have recently been established. The present paper extends the use of these methods for the analysis of dichotomously measured performance characteristics, the susceptibility to lodging, in particular. The procedures examined were based on generalized linear models in which the expected conditional mean of the susceptibility to lodging was used as an explanatory variable to express the environmental effects of a given environment. Through the use of logistic transformation the approach extends previous methods developed for continuous response variables to binary response variables. Models were subsequently used to obtain measures of susceptibility to lodging of each barley variety in terms of environmental variation. While the emphasis is restricted to lodging, similar methods can also be applied to other performance characteristics.