Yield Stability and Adaptability Analysis of Sorghum Mutant Lines Resulted from Gamma Rays Induced Mutation

Abstract Sorghum has a great potential to be grown and developed for food in Indonesia. The objective of this study was to obtain information on the stability of grain yield from several sorghum hopes mutant lines at 10 test locations. The CTY-43 mutant line was used as the genetic material and was irradiated with a 300 Gy dose of gamma rays. The pedigree method was used for selection, starting with the M2 generation, by choosing plants with better agronomic traits than the parent and national sorghum varieties. After going through the stages of selection, observation, and preliminary yield tests, 10 promising mutant lines were selected for yield stability tests. The mutant lines were grown during the rainy season of 2020/2021 and the dry season of 2021 in 10 locations, with three control genotypes (CTY-43 mutant line as the parent and Kawali and Numbu as national sorghum varieties). The experiments were arranged in a randomized block design, with three replicates. The presence of significant genotype-environment (GxE) interactions in this study requires additional stability analysis. The results showed that there were two mutant lines with seed yields higher than those of all control genotypes. The GH-1 mutant line has 6.15 t/ha seed production and is stable in all seasons and locations (βi = 0.970 and Sdi = 0.054). The GH-4 mutant line produced the highest seed yield of 6,43 t/ha and was adapted to an optimal environment, similar to the Bogor area (βi = 1.252 and Sdi = 0.117).