Heritability, Expected Genetic Advance, and Genotype by Trait Analysis for Grain Yield and Agronomic Traits in Durum Wheat under Irrigated and Rainfed Conditions

According to Raje and Rao (2000) genetic variability is essential in order to realize response to the selection [18]. Where: aij = The mean value of genotype i for trait j βj = The mean value of all genotypes for trait j σj = The standard deviation of trait j among genotype means λo = The singular value for Principal Component (PCn) ξin = The PCn score for genotype i ηjn = re for trait j ξij = ξij = residual associated with genotype i in trait j To achieve trait-focused scaling between genotype and trait scores the singular value has to be absorbed by the singular vector for genotype and for traits That is, ... Because n= 2 in a biplot, only PC1 and PC2 are retained in the model and such a model tends to be best for extracting patterns and rejecting noise from the data. According to Table 3, maximum genetic advance of 39.792% followed by 35.286% and 34.063% was recorded in grain weight per spike, stem weight and number of grains per spike, respectively in irrigated conditions. According to polygon view of the dataset there are eight vertex genotypes in the irrigated conditions (Figure 2a) which are genotypes G28, G32, G36, G47, G11, G15, G21 and G26.