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The traditional winter wheat (Triticum aestivum L.) production area on the North American Great Plains extended as far north as southern Alberta, Canada. This paper reviews a research and development program initiated with the objective of expanding production north and east into higher winter stress areas of the Canadian prairies. Winter survival was considered the main limitation to production in this region. However, the widespread adoption of no-till seeding into standing stubble for snow trapping has proven to be a successful method of overwintering wheat if cold hardy cultivars are grown using recommended management practices. Plant breeding improvements have increased production potential and winter wheat has become western Canada's third largest wheat class. Average commercial yields of 149, 125, and 118% of spring wheat in Manitoba, Saskatchewan, and Alberta, respectively, have demonstrated the high yield potential that can be realized while employing environmentally sustainable crop management practices. In light of current environmental concerns, changing weather patterns, diminishing world wheat reserves, and an ever increasing global population to feed, one would assume that winter wheat production in western Canada would be widely embraced. However, marketing obstacles and difficulties inserting winter wheat into rotations, both of which have a direct influence on farmers' net returns, remain to be overcome for this potential to be fully realized. [ABSTRACT FROM AUTHOR]

Wheat (Triticum spp. L) production needs to be improved to meet the needs of a global population of >9 billion people by 2050. Increasing the productivity of the crop under conditions of abiotic and biotic stress to achieve food security continues to be a challenging proposition. Wheat stem sawfly (WSS) (Cephus cinctus Norton) has been considered as a serious pest of wheat since the late 19th century, causing devastating losses of wheat productivity in the Northern Great Plains of United States and regions of Canada. Developing resistant varieties of wheat that show consistent agronomic performances in varying environments is an effective strategy to manage WSS infestations. To achieve this goal, it is necessary to understand the underlying mechanisms of WSS infestation, damage, subsequent response of the host plant, and resulting yield losses. The review focuses on genetics, breeding, and development of solid stem (SS)‐mediated WSS resistance in wheat since it has been the most effective method of genetic resistance in reducing wheat yield losses. Furthermore, the knowledge gaps that need to be addressed to develop an effective resistant cultivar against WSS are also discussed. Core Ideas: Wheat stem sawfly is a major problem with no insecticide control mechanism.Solid stem varieties have been employed for wheat stem sawfly resistance.The review focused on providing comprehensive information on solid stem genetics, breeding, and development. [ABSTRACT FROM AUTHOR]

Winter canola (Brassica napus L.) production has increased in the Great Plains as producers seek a rotational and alternative crop to winter wheat (Triticum aestivum L). However, limited information is available if canola could be used for dual‐purpose without significantly affecting grain yield. The objectives of this study were to (a) investigate dual‐purpose potential and (b) impact of companion crops on growth, survival, biomass, and grain yield of canola. The study was conducted in 2011 and 2012 at Garden City, KS. The experimental design of the study was a randomized complete block design with split‐plot arrangement. Main plot treatments were a factorial of canola cultivars (Griffin or Wichita) and companion crop treatments (none, spring triticale [× Triticosecale Wittm. ex A. Camus], winter triticale, radish [Raphanus raphanistrum subsp. sativus (L.) Domin], and turnip [Brassica rapa var. rapa L.]), and the split‐plot treatments were single‐purpose (grain only) or dual‐purpose (grain and forage) management. Averaged across cultivars and years, grain yield was 70% greater when canola was used for single‐purpose (grain‐only) compared with dual‐purpose. Griffin grain yield tended to be relatively greater than Wichita in dual‐purpose use. Averaged across the two years, turnip as a companion crop decreased canola yield by 38% but resulted in greater forage accumulation. In conclusion, dual‐purpose canola has a grain yield penalty, but effects may vary by cultivar. Companion cropping did not benefit canola and in some cases negatively affected grain yield. When grain production is the primary objective, both companion cropping and forage use should be avoided. [ABSTRACT FROM AUTHOR]

Legumes have potential to transfer fixed N to nonlegume crops via grazing or decomposition as well as improve production, seasonal distribution, nutritive value, soil structure, and fertility in forage systems. This article summarizes the legume establishment, management, and grazing production experiments conducted in the southern Great Plains. It attempts to give perspective on the current state of producer adoption and the potential for future research to improve legume adoption. Several medics (Medicago spp.) and clovers (Trifolium spp.) are compatible and can be established with tall fescue [Schedonorus arundinaceus (Schreb.) Dumort]; however, due to limited precipitation, these have not reliably regenerated. Hairy vetch (Vicia villosa Roth) required annual establishment and was not as economical as N fertilizer in the perennial grass systems, but it was profitable and comparable to the annual system with 112 kg N ha-1 by conventional fertilizer. Alfalfa (Medicago sativa L.) may have the greatest potential in the southern Great Plains with cool-season perennial grass systems like tall fescue when planted in a checkerboard orientation. An alternative approach for utilizing legumes may be to limit grazing access in pure stands similar to a supplementation program during periods of limited forage production or quality. There is a need for greater research including germplasm and rhizobia evaluations, improved seed production, weed control, and grazing before producer adoption becomes widespread. Future research should address constraints including legume establishment, management practices that extend the life of legumes in forage systems, and appropriate economic analysis of proposed novel systems. [ABSTRACT FROM AUTHOR]

Big bluestem (Andropogon gerardii Vitman) is a native grass of the North American tallgrass prairie, used as a forage crop and as a possible biofuel feedstock. Understanding the genetic diversity of big bluestem can enable better classification of accessions and increase the ability to recognize unique genetic variation for use within breeding programs. Previous studies of the genetic diversity of big bluestem have generated mixed conclusions; further study is warranted to provide clarification of the genetic structure. Genetic diversity was measured both among and within three groups of big bluestem populations: natural populations collected in Wisconsin, natural populations from the northeastern United States, and cultivars or accessions available through various gene banks (mostly originating in the Great Plains). A total of 417 amplified fragment length polymorphism loci were used for principal coordinate analysis, analysis of molecular variance, and Mantel tests. Results indicate that germplasm groups represent three distinct genetic pools with overlapping regions. Partitioning of genetic variance for each of the three groups revealed significant variance among ecoregions and hardiness zones and among populations within ecoregions and hardiness zones. Unique big bluestem germplasm is present outside of the Great Plains, providing opportunities to increase genetic variation within breeding germplasm. Efforts should be made to preserve these genetic resources. [ABSTRACT FROM AUTHOR]

Wheat streak mosaic virus (WSMV), is a potentially devastating disease of common wheat (Triticum aestivum L.) in the Great Plains of North America. So far, two genes conferring resistance to WSMV have been named and used in cultivar improvement. Here we report a new source of resistance that was derived from a wheat-Thinopyrum intermedium (Host) Barkworth & D.R. Dewey ditelosomic addition line containing, in addition to the wheat chromosome complement, a pair of long arm telochromosomes from Th. intermedium previously believed to be of group-4 origin. New molecular marker and genornic in situ hybridization analysis revealed that this telochromosome is homeologous to the group-7 long arms and belongs to the S genome of Th. intermedium. Accordingly, this chromosome was designated as 7S#3L. One compensating Robertsonian translocation was obtained where the 7S#3L arm was translocated to the short arm of wheat chromosome 7B, resulting in the T7BS∙7S#3L translocation chromosome. Homozygous T7BS∙7S#3L lines were evaluated for their resistance to WSMV and Triticum mosaic virus (TriMV). The T7BS∙7S#3L stock confers resistance to WSMV at 18 and 24°C. The T7BS∙7S#3L stock also confers resistance to TriMV at 18°C but is not effective above 24°C. Based on chromosome position and effective resistance to WSMV at 24°C where both Wsml and Wsm2 are ineffective, the new gene in T7BS∙7S#3L is designated as Wsm3. [ABSTRACT FROM AUTHOR]