GRAIN YIELD STABILITY ANALYSIS USING PARAMETRIC AND NONPARAMETRIC STATISTICS OF BULGARIAN AND HUNGARIAN COMMON WINTER WHEAT GENOTYPES

The research was conducted in the period 2020-2023 on the experimental field at the IPGR "K. Malkov", town of Sadovo. 5 Hungarian varieties, 16 advanced lines and 4 Bulgarian varieties of common winter wheat were evaluated for grain yield and stability. The stability of the grain yield was determined by the variances of stability (sigma i(2) and Si-2), equivalency (Wi), the criterion of phenotypic stability (Ysi), regression coefficient b. and general adaptability. The highest average yield for the study period was obtained from MV-Nemere 864.4 kg/da, followed by RU179/1400 and MV-Nador -766.6 and 766.5 kg/da. The yield formed by the Hungarian varieties is relatively high and they are of interest for selection improvement work. In terms of grain yield, the lines RU 129/3053 and RU 177/486 have a complex stability assessment. The variety Sadovo1 is defined as very stable in different environments and valuable for selection programs.