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Evolutionary plant breeding (EPB) is a breeding method that was used to create wheat (Triticum aestivum L.)-evolving populations (EP), bi-parental and composite-cross populations (BPPs and CCPs), by using natural selection and bulking of seed to select the most adaptable, diverse population in an environment by increasing the frequency of favorable alleles in a heterogeneous population. This study used seven EPs to evaluate EPB in its ability to increase the performance of agronomic, quality, and disease resistance traits and adaptability across different precipitation zones. The populations were tested in field trials in three diverse locations over 2 years. Least significant differences showed the EPs performance was dependent on their pedigree and were statistically similar and even out-performed some of their respective parents in regards to grain yield, grain protein concentration, and disease resistance. Stability models including Eberhart and Russel&rsquo, s deviation from Regression (), Shukla&rsquo, s Stability Variance (), Wricke&rsquo, s Ecovalance (), and the multivariate Additive Main Effects and Multiplicative Interaction (AMMI) model were used to evaluate the adaptability of the EPs and their parents. The BPPs and CCPs demonstrated significantly greater stability over the parents across precipitation zones, confirming the capacity of genetically diverse EP populations to adapt to different environments.

Selection of winter wheat cultivars with long coleoptiles is an important component of improving emergence, weed suppression and grain yield in low rainfall regions of the world. Seven winter wheat cultivars were hybridized in a Griffing’s half-diallel mating design, method 2 (reciprocals excluded, parents included), model 1 (fixed), and the progeny analyzed for coleoptile length in the F1 through F4 for response to selection, general combining ability (GCA), specific combining ability (SCA) and heritability. Highly significant differences existed for GCA among progeny in each generation. SCA was highly significant in the F1, F2 and F4, although SCA estimates were inconsistent among generations in each progeny population. The SCA/GCA ratio was 0.15, 0.11, 0.06 and 0.04 in the F1 through the F4, respectively, indicating that additive effects increased with homozygosity. Broad-sense heritability for coleoptile length was estimated at 0.86, 0.76, 0.60 and 0.78 for the F1 through the F4, respectively. Realized heritabilities ranged from −0.16 to 0.85 with a mean of 0.32 in the F3 and ranged from −0.68 to 0.68 with a mean of 0.13 in the F4. Spearman’s rank correlation coefficients (RS) were significant for all generation comparisons except the F1:F2, indicating that changes in rank for coleoptile length were insignificant. Cultivars with long coleoptiles and high GCA were the best parents for improving coleoptile length. Sustained selection over generations for coleoptile length was more effective than one generation of selection for genotypes both with and without reduced height genes.