Estimation of Genetic and Phenotypic Correlation Coefficients and Path Analysis of Yield and Yield Contributing Traits of Bread Wheat ( Triticum aestivum L.) Genotypes

Abstract

Thirty bread wheat genotypes were tested to assess the association among yield and yield contributing traits and determining the direct and indirect effect of the traits on the grain yield. The genotypes were grown in alpha-lattice design at Tongo sub-center of Assosa Agricultural Research Center and Kulumsa Agricultural Research Center in 2015. Grain yield showed significant (p≤0.01) positive phenotypic correlations with thousand kernels weight, above ground biomass, harvest index, hectoliter weight and plant height at each location except for kernels per spike at Tongo and days to maturity at Kulumsa. Similarly, grain yield showed significant (p≤0.01) positive genotypic correlations with 1000 kernel weight, above ground biomass, harvest index,, hectoliter weight and plant height at Tongo and only with above ground biomass and harvest index at Kulumsa. Likewise, significant (p≤0.01) positive and negative phenotypic and genotypic correlations between the yield components were observed at each location. As per the path analysis above ground biomass and harvest index showed high positive phenotypic direct effect on grain yield at each location whereas low positive phenotypic direct effect observed for characters plant height and number of kernel per spike at Tongo and hectoliter weight at Kulumsa. Similarly, at genotypic level above ground biomass and harvest index showed highly significant direct effect on the grain yield at each location. Generally, it has been observed the presence of relationships in the tested traits of the genotypes studied. Hence, Selection and hybridization on those genotypes based on the trait with high positive correlation coefficient and direct effect on grain yield can be recommended for farther yield improvement of bread wheat at respective location.