Abstract

Two different sets of field experiments were conducted from 2016 to2018 main cropping seasons. In experiment I, 15 GSR genotypes including two checks were evaluated in Fogera and Shire-Maitsebri and its objective was to select cold tolerant and high yielding GSR rice varieties. In experiment II, a total of 20 GSR genotypes including one check were evaluated in Pawe and Assosa with the objective of selecting high yielding and disease resistance in the lowland ecosystems of Ethiopia. In both sets of experiments, the trials were laid out in randomized complete block design with three replications. The combined analysis of variance in experiment I revealed significant difference on most of agronomic traits (P≤0.01). Three genotypes (G2, G6 and G4) showed significant difference than the standard checks on grain yield and gave grain yield advantage of 32.6 %, 27.9 % and 22.3 %, respectively. GGE-bi-plot analysis revealed that G2 and G6 are high yielding and most stable among tested genotypes in both environments. There was no grain sterility problems observed in both genotypes (G2 &G6) and had better panicle exertion which can fit the cold tolerant phenotypic characteristics. G2 has been released in 2020 as variety by giving local name “Selam” which means Peace and recommended for large scale production. In Experiment II, the mean grain yield of the 20 lowland green super rice genotypes ranged from 2730.30kgha-1(G7) to 3683.40 kg ha-1 (G13). The combined analysis over the environments revealed that no genotype significantly gave higher yield than the standard check. There was no genotype for wider adaptability. However, the separate location analysis revealed that at Assosa, one genotype (G13) and at Pawe two genotypes (G14 and G1) gave significantly higher yield than the standard check with yield advantage of 26.7%, 21.7% and 20.6%, respectively.

Keywords: GSR; Cold; Stability; Rice