Seasonal Effects and Genotypic Responses for Grain Yield in Semi-dwarf Wheat

Evaluation of Kenya Stem Rust Observation Nursery Wheat Genotypes for Yield and Yield Components under Artificial Rust Conditions

“…GY had the least heritability estimates because it is a complex trait controlled by multiple genes and influenced by the interaction of the genotypic expression of yield components and the environmental variables. The heterogeneity of environmental conditions over time tends to mask the genetic potency of traits determined by multiple genes [8,9].…”

“…Grain yield is the most important trait for selection in all field crop improvement programs. Grain yield is controlled by additive genes and has a high degree of interaction with environmental factors [8,9]. Breeding for yield and grain quality is designed to fit the target environment because of its significance during selection for variety replacement while maintaining food security [10,11].…”

Evaluation of Bread Wheat Varieties Performance and their Stability at Levels of Seeds Fogging with Seaweed Extract Alga-600 and Types of Compound Fertilizers

“…It is concluded from the foregoing that the instability of grain yield per hectare and other traits is due to genetic differences between the varieties and to environmental fluctuations. Table (7) shows the analysis of variance results for stability by the method of Eberhart and Russell [9], and from it is clear that the mean square of the environments (linear) was highly significant for all studied traits, indicating that the response to different environments is under genetic control [15]. It appears that the mean squares of the linear component of varieties x environments interaction when tested against the pooled deviation was significant at the 1% probability level for the two traits of plant height and number of grains per spike, but not significant for all other traits.…”

“…The pooled deviation test against the pooled experimental error indicated that its mean square was not significant for all studied traits. It is noted that the linear component of varieties x environments interaction was not significant for most traits except plant height and number of grains per spike, and the pooled deviation was not significant for al traits, indicating that the deviation from the linear function actually contributes to the deviation in the stability of the varieties of these environments for the varieties x environments interaction with these traits [16], and that the deviation is the most important stabilizing parameter, the most important stabilizing parameter, and it is clear from Table (7) also that the mean squares of each of the six bread wheat varieties was not significant for all studied traits, an indication of the deviation from the regression (S 2 d i ) is not significant for all varieties and for the studied traits. Table (8) shows the values of the regression coefficient B i (which determines the response of varieties to different environments, which is measured by the linear regression of the variety mean over the average of the varieties in each environment) and the mean deviation from the regression for each variety (S 2 d i ).…”

“…Yang and Baker [6] indicated that the instability of the grain yield between genotypes across different environments may arise as a result of the expression of different groups of genes in different environments or the difference in responses of the same group of genes to different environments. The stability of grain yield between genotypes can be expressed as a linear response to the environmental yield and the deviation from that response [7]. The ideal genotype generally shows low variance of genetic x environment interaction above average response to environmental gain and smaller deviations from the expected response within the target environment.…”