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Parallels exist between the domestication of new species and the improvement of various crops through selection on traits which favor the sowing, harvest and retention of yield potential and the directed efforts to improve their agronomics, disease resistance and quality characteristics. Common selection pressures may result in the parallel selection of orthologs underlying these traits and homologies between crop species can be exploited by plant breeders to improve germplasm. Perennial grains and oilseeds are a class of proposed crops for improving the diversity and sustainability of agricultural systems. Maximilian sunflower (Helianthus maximiliani Schrad.) is a perennial crop wild relative of sunflower (Helianthus annuus L.) and a candidate perennial oilseed species. Understanding parallels between cultivated H. annuus and H. maximiliani may provide new tools for the development of Maximilian sunflower and other wild relatives of sunflower as crops to enhance functional diversity in cropping systems. F2 populations of Maximilian sunflower segregating for traits associated with the domestication ideotype of cultivated sunflower including branching architecture, capitulum morphology and flowering time were developed to investigate parallels between H. maximiliani and H. annuus. Genotype-by-sequencing (GBS) was employed to genotype novel Maximilian sunflower populations and perform quantitative-trait-loci (QTL) analysis. A total of 11 QTL in five regions were identified across 21 linkage groups using 4142 GBS derived single nucleotide polymorphism markers called using the sunflower reference genome as a guide. A major QTL on linkage group 17b, associated with aspects of floral development and apical dominance, was discovered and corresponds with a known domestication QTL hotspot in H. annuus and candidate genes were identified. This suggests the potential to exploit orthologs for neo-domestication of H. maximiliani for traits such as branching architecture, timing of anthesis, and capitulum size and morphology for the development of a perennial oilseed crop from wild relatives of cultivated sunflower.

Maximilian sunflower (Helianthus maximiliani Schrad.), a crop wild relative of sunflower (Helianthus annuus L.), has been identified as a species of interest for the development of a perennial oilseed crop. Knowledge of the diversity, the potential for crop development, and genomic resources of this crop wild relative is limited. To facilitate its use in breeding programs, a baseline characterization of locally adapted germplasm is required to develop informed breeding strategies. Individuals were collected from nine sites in southern Manitoba, Canada, and characterized for phenotypic and genotypic divergence to estimate traits of interest for the implementation of a breeding program in Maximilian sunflower. Genotype-by-sequencing was used to characterize population genetic parameters and identify candidate single nucleotide polymorphisms (SNPs) associated with phenotypic divergence and environmental differences between collection sites. Candidate SNPs associated with frost-free period, temperature during the primary vegetative growth period, elevation, soil CaCO₃ equivalent, days to anthesis and capitulum size were identified and may be useful for the improvement of H. maximiliani and crop species related to cultivated sunflower. Associations between temperature, population structure, and overall plant size were also identified, suggesting phenotypic divergence across a local temperature gradient. The sampled Maximilian sunflower populations exhibited a high degree of polymorphism, low levels of inbreeding, and a highly heterozygous genome at the local scale, traits that favor the establishment of locally adapted germplasm pools. There appears to be sufficient variation to make selections for agronomic traits in local germplasm of Maximilian sunflower to support its development as a perennial oilseed.

In the interest of diversifying the global food system, improving human nutrition, and making agriculture more sustainable, there have been many proposals to domesticate wild plants or complete the domestication of semidomesticated orphan crops. However, very few new crops have recently been fully domesticated. Many wild plants have traits limiting their production or consumption that could be costly and slow to change. Others may have fortuitous preadaptations that make them easier to develop or feasible as high-value, albeit low-yielding, crops. To increase success in contemporary domestication of new crops, we propose a pipeline approach, with attrition expected as species advance through the pipeline. We list criteria for ranking domestication candidates to help enrich the starting pool with more preadapted, promising species. We also discuss strategies for prioritizing initial research efforts once the candidates have been selected: developing higher value products and services from the crop, increasing yield potential, and focusing on overcoming undesirable traits. Finally, we present new-crop case studies that demonstrate that wild species’ limitations and potential (in agronomic culture, shattering, seed size, harvest, cleaning, hybridization, etc.) are often only revealed during the early phases of domestication. When nearly insurmountable barriers were reached in some species, they have been (at least temporarily) eliminated from the pipeline. Conversely, a few species have moved quickly through the pipeline as hurdles, such as low seed weight or low seed number per head, were rapidly overcome, leading to increased confidence, farmer collaboration, and program expansion. Fil: DeHaan, Lee R.. The Land Institute; Estados Unidos Fil: Van Tassel, David L.. The Land Institute; Estados Unidos Fil: Anderson, James A.. University of Minnesota; Estados Unidos Fil: Asselin, Sean R.. University of Manitoba; Canadá Fil: Barnes, Richard. University of Minnesota; Estados Unidos Fil: Baute, Gregory J.. University of British Columbia; Canadá Fil: Cattani, Douglas J.. University of Manitoba; Canadá Fil: Culman, Steve W.. Ohio State University; Estados Unidos Fil: Dorn, Kevin M.. University of Minnesota; Estados Unidos Fil: Hulke, Brent S.. United States Department of Agriculture. Agriculture Research Service; Estados Unidos Fil: Kantar, Michael. University of British Columbia; Canadá Fil: Larson, Steve. Forage and Range Research Laboratory; Estados Unidos Fil: David Marks, M.. University of Minnesota; Estados Unidos Fil: Miller, Allison J.. Saint Louis University; Estados Unidos Fil: Poland, Jesse. Kansas State University; Estados Unidos Fil: Ravetta, Damián Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Museo Paleontológico Egidio Feruglio; Argentina Fil: Rude, Emily. University of Wisconsin; Estados Unidos Fil: Ryan, Matthew R.. Cornell University; Estados Unidos Fil: Wyse, Don. University of Minnesota; Estados Unidos Fil: Zhang, Xiaofei. University of Minnesota; Estados Unidos

Perennial grains are demonstrating a greater probability of occupying land currently dedicated to other agricultural production. Arable land that is currently in use for forage or annual crop production becomes utilized. Breeding materials for the introduction of perennial grains directly into the human food chain has required utilizing existing plant materials in the domestication of species or manufacturing diverse crosses to introduce perenniality into existing crops. In the domestication of intermediate wheatgrass (Thinopyrum intermedium (Host), Barkworth and Dewey), existing forage cultivars or plant accessions were used to develop populations selected for grain production. A comparison of Cycle 3 materials from The Land Institute (TLI), Salina, KS, USA to USDA-Germplasm Resources Information Network (GRIN) accessions took place under space-planted field conditions at Carman, MB, Canada from 2011 to 2014. One hundred plants (75 TLI and 25 GRIN identified in May 2012) were followed through three seed harvests cycles with phenological, morphological and agronomic traits measured throughout. Selection for seed productivity (TLI materials) reduced the importance of biomass plant−1 on seed yield plant−1, leading to an increase in harvest index. Principal component analysis demonstrated the separation of the germplasm sources and the differential impact of years on the performance of all accessions. Path coefficient analysis also indicated that plant biomass production was of less importance on seed yield plant−1 in the TLI materials. Analysis removing area plant−1 as a factor increased both the importance of biomass and heads on seed yield cm−2 in the TLI materials, especially in the first two seed production years. Plant differences due to selection appear to have reduced overall plant area and increased harvest index in the TLI materials, indicating progress for grain yield under selection. However, a greater understanding of the dynamics within a seed production field is needed to provide insight into the development of more effective selection criteria for long-term field level production.

Production agriculture relies primarily on seeding of annual crops for food, feed, fuel, and fibre in western Canada. Annual seeding and harvesting commonly leave land non-productive for a portion ...