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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.

Resistance to strawbreaker foot rot (caused by Oculimacula yallundae Crous & W. Gams and O. acuformis Crous & W. Gams), stripe rust (caused by Puccinia striiformis Westend. f. sp. tritici iformisEriks.), and Cephalosporium stripe (caused by Cephalosporium gramineum Nisikado and Ikata) are important traits for winter wheat ( Triticum aestivum L.) cultivars produced in the Pacific Northwest region of the United States. The objective of this research was to develop an adapted winter wheat cultivar with effective resistance to these diseases. ‘Puma’ (Reg. No. CV-1097, PI 670038) soft white winter wheat ( Triticum aestivum L.) was developed and released in August 2013 by the Agricultural Research Center of Washington State University. Puma was tested under the experimental designations 5J030731, 5J030731–2, and WA008134, which were assigned through progressive generations of advancement. Puma is a semidwarf cultivar adapted to intermediate to high rainfall (>400 mm of average annual precipitation), unirrigated wheat production regions of Washington. Puma is resistant to strawbreaker foot rot, has high-temperature, adult-plant resistance to the stripe rust pathogen, is tolerant to Cephalosporium stripe, is intermediate in height, has midseason maturity, and has a high test weight and grain yield potential. Puma has end-use quality properties similar or superior to those of ‘Stephens’, ‘Brundage 96’, and ‘Xerpha’.

Many of the current soft white winter (SWW) wheat (Triticum aestivum L.) cultivars produced in Washington are adapted to specifi c environments. The objective of this research was to develop a high yielding, disease resistant SWW cultivar with competitive yield potential for all Washington winter wheat production environments. 'Xerpha' (Reg. No. CV-1045, PI 645605) SWW wheat was developed by the Agricultural Research Center of Washington State University (WSU) and released in 2008. It was selected from an 'Eltan'/'Estica' cross made in 1999 and advanced to the F 5 in the greenhouse by a modifi ed single seed descent breeding strategy. Successive progeny were advanced under fi eld conditions by a modifi ed pedigree-bulk breeding method under the experimental designations SSD01061 and eventually WA007973. Xerpha was the highest, or among the highest, yielding SWW cultivars in every precipitation zone in the WSU Extension Uniform Cereal Variety Testing Program (EUCVTP) trials in 2006, 2007, and 2008. It was released as a replacement for 'Madsen' and Eltan on the basis of its superior grain yield in Washington's low ( 500 mm AAP) precipitation zones; excellent grain volume weight; strong cold tolerance, and high-temperature, adult-plant (HTAP) resistance to stripe rust (caused by Puccinia striiformis Westend. f. sp. tritici).

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.

With 4 tables Abstract Perennial wheat is emerging as a potential long-term response to agroecological problems resulting from soil erosion. We conducted field scale trials of 31 F5 (2005–2006) and five F6 (2006–2007) amphiploid breeding lines derived from Thinopyrum elongatum/Triticum aestivum (cv. ‘Chinese Spring’)//T. aestivum (cv. ‘Madsen’) crosses. Here, we report results on post-sexual cycle regrowth (PSCR) and grain yield in the amphiploid lines and two annual wheat cultivars from three locations in Washington State, USA. Per cent plants per plot exhibiting PSCR varied significantly among genotypes and ranged from 18% to 81% (μ = 45%) in the amphiploids, with no PSCR apparent in the annual cultivars. The mean grain yields of the amphiploid lines were 632, 2086 and 2226 kg/ha at each location; approximately 44% (range = 20–93%) of the annual wheat. Absence of genotype × environment interactions for PSCR suggests that selection for broad adaptation of the PSCR trait across locations and years would be possible. No relationship existed between grain yield and regrowth among the lines exhibiting PSCR, indicating potential for simultaneous selection of these traits.