Comparison of rank-based stability statistics for grain yield in rainfed durum wheat

Abstract

Several rank-based stability statistics are in use, but little information is available on their repeatability and accuracy. The main objective was to examine the repeatability, similarity and accuracy of the estimates of mean yields and 10 rank-based stability statistics calculated from 25 rainfed durum wheat genotypes grown in 21 diversified rainfed environments. Spearman’s rank-correlation coefficients and Kendall’s coefficient of concordance were used to estimate the repeatability and similarity of stability statistics, while the coefficient of variation from resampling correlations obtained by bootstrap method was used to quantify their accuracy. Correlations between the estimates from each of the rank-based stability statistics obtained from single-year results were very low and non-significant, suggesting that single-year results could not serve as a basis to quantify phenotypic stability. The accuracy for the repeatability of stability statistics was found to be poor, whereas the accuracy for similarities of stability statistics was high.