Stability parameters of 20 genotypes of white mustard were evaluated under
four environments in two locations and assessed using three different stability
methods. These method were Eberhart and Russell (1966), Perkins and Jinks (1968)
and Freeman and Perkins (1971). The investigation included five characters (plant height, number of primary
branches, number of secondary branches, number of pods on main branch and seed
yield). Results revealed significant genotype x environment interactions for all studied
traits and the response to environmental changes of each genotype differed as
indicated by M.S. pooled deviation and heterogeneity items. Wider ranges of
regression coefficient values were observed from the studied stability methods
suggesting possibility of selection for specific genotypes patterns. Four genotypes (6,
10,12, 13)were most stable for studied characters in four environments. Stability for yield components such as seed yield per plant should be
considered when breeding for yield stability in white mustard. Comparing the different
stability methods revealed that Eberha"rt & Russell and Freeman & Perkins were of
equal importance in assessing stability and cleared that there were significant genetic
background variations between white mustard genotypes and response to
environmental conditions. Genetic characterization of white mustard genotypes by SOS-PAGE analysis
of protein fractions revealed that the differences in the banding profile pattern in the
altered environment (clay vs. sandy soils). Moreover, some other protein bands were
also found ir. the sandy soil more than in the clay soil.