Genotype X environment Interaction and Stability of Oil Content of Sesame (Sesamum indicum L.) Genotypes in Northern Ethiopia

Abstract

The experiment for oil content analysis was conducted for two growing seasons under rainfed condition (2012-2013) in Humera and Dansha, and in a single year (2013 cropping season) in Sheraro (comprising a total of five environments). The experiment comprised of 13 sesame genotypes, laid out in a randomized complete block design of three replications with the objective of determining the magnitude of Genotype x Environment Interaction (GEI)and oil content. here was highly significant (p<0.01) oil content variation based on genotypes, environments and GEI resulting 26%, 42.7 % and 30.9% of the total sum of squares for the oil content variation respectively.  The mean of the oil content was 53.9%, with genotypes G4 and G11 with the highest oil content (55.1 %) each, and G8 with the lowest oil content (51.4 %). G4 was the exceptional genotype with the highest oil content (55.1 %) and oil yield (512.9 kg/ha). Based on the Environmental Index (EI) analysis, Environments E4 and E5 were the favourable environments, while E1, E2 and E3 were unfavourable environments for sesame oil production. According to the AMMI1(Additive main effects and multiplicative interaction) bi-plot, Genotypes G4, G13 and G10 with oil the content of 55.1%, 54.7 and 54.2 respectively, were stable genotypes. On the other hand, genotypes G2, G8, G9, G3 and G1 were unstable genotypes in most of the environments. The AMMI 2 bi-plot showed that, genotypes G2, G3 and G9, with long vector length, were specifically adaptable genotypes and genotypes G10, G12, G4 and G7 with shorter vector length were widely adaptable in most of the environments for their oil content. Oil content of sesame varies highly both across years and locations.