Brief Summary of Minutes of Annual Meeting

Plant Introduction Research Unit and the North Central Regional Plant Introduction Station (NCRPIS): 

Obj 1: Development and utilization of diverse plant genetic resource (PGR) collections (germplasm) are essential, valuable sources of genetic diversity for use in scientific research, education, and crop improvement programs in the U.S. and internationally. The NCRPIS is a key element of the National Plant Germplasm System (NPGS), specializing in heterozygous, heterogenous, outcrossing crops and their wild relatives of maize, vegetables, oilseeds, woody and herbaceous ornamentals, and a wide variety of crops such as amaranth, perilla, quinoa and more. For the past 72 years, the crop collections important to the North Central Region (NCR) have been supported through the partnerships with Hatch Multi-State Project NC-007, the USDA-Agricultural Research Service, the State Agricultural Experiment Stations of the NCR, and Iowa State University (ISU).   These resources are used to improve crop production genetics and technologies to address challenges related to climate instability, changing abiotic and biotic stress pressures, a to enhance the health and nutrition of society, and demands for bioenergy resources.

Curatorial personnel acquire, maintain and conserve, phenotypically evaluate, genetically characterize, document, and distribute plant genetic resources and associated information.  Collection development is a complex process, and depends on access to resources controlled by state, national, international, and both public and private entities. Identification of gaps in PGR collection representation is necessary in order to develop acquisition priorities, and gaps are addressed via exploration and/or exchange with other collections. 

Obj 2, 4, 5: Germplasm Acquisition, Maintenance and Distribution: North Central Regional Plant Introduction Station (NCRPIS) personnel acquired 292 new accessions (holdings total 54,774 accessions) and distributed 61,124 units of seed to fulfill 1,414 orders from 1,000 requestors, of 23,229 unique accessions.  Distribution of 42% of the entire collection holdings reflects very high demand. About 52% of the distributions were to US recipients, and 48% to international recipients; international demand was unusually high.  Over the past five years, researchers of the 12 Land Grant institutions of the NCR have received nearly 30,200 seed distributions.

Collection availability overall stands at 76%. More than 1,840 seed health tests were performed to comply with phytosanitary import requirements associated with  international maize and sunflower seed requests.  ELISA testing of all Cucurbita seedlings (2,572) was done prior to transplanting to the field to ensure that seedlings were free of squash mosaic virus. Field and greenhouse inspections were conducted to ensure that all plantings were free of diseases, and samples were cultured for of those specimens with observable symptoms. Approximately 4,461 accessions were tested for viability as part of routine maintenance activities to ensure the quality of the collections; 40% of the entire collection is in need of viability testing. The viability team has adopted a smaller sample/rep, multiple rep testing strategy to rapidly id seedlots that may have issues and require more testing; this has greatly increased our testing capacity. Backup seed lots were sent of 779 accessions to the National Laboratory for Genetic Resource Preservation (NLGRP) in Ft. Collins, CO and 300 accessions were sent to the Global Seed Vault in Svalbard, Norway.

Approximately 1,250 accessions were grown for seed increase in Ames across all taxa, including perennials that will be maintained until seed increase goals are achieved. Tropical location maize increases for unadapted tropical maize included 250 sent to a commercial nursery provider in Mexico in August 2017 (due to lack of temperate adaptation) and 125 sent in fall 2018, with excellent quality seed return, and 25 highland tropical maize accessions with old, low viability seed were sent to CIMMYT for contract increase at their high altitude Tolucca site. More tropical accessions from Kasetsart University, Thailand were grown for  increase in a ISU campus greenhouse under APHIS permit, but the polar vortex resulted in damage and poor seed return. Other Ames regeneration efforts included 172 maize; oilseeds, 257; vegetables, 179; amaranth, panicum, quinoa, etc., 430; and ornamentals, 109.  The Ornamentals project is now use other ISU farm locations for tree species regeneration to achieve isolation. Seed increase priorities include accessions identified with declining viability.

Two newly developed vernalization rooms equipped with LED lighting, heat and humidity controls supported early growth and vernalization of Brassica accessions which were transplanted to the field.

Obj 3: Evaluation and Characterization: More than 610 accessions were grown for various observation trials; 22,426 observations and 4,866 images were loaded to the GRIN-Global database. The Brassica rapa collection is being evaluated for winter/spring type determination, facilitating regeneration management decisions. Priority regenerations include A new dataset was collected of millet observations for temperate adaptation.  Pedigree information of all expired maize PVP lines was added to GRIN.  Optical seed sorters were employed for the first time to improve seed lots of maize prior to planting, and also by ISU campus researchers for sorghum, millet, and soybeans.

Obj 4: Software Development: Our development staff released an enhanced Viability wizard, software used for automation of viability testing capture and transfer to the GRIN-Global database, and an enhanced Order wizard, and five new Curator Tool versions. These products support management of associated information, curatorial workflows, and public access to information associated with germplasm that facilitates their use.

Obj 5: Tours were provided to more than 400 visitors, and professional findings were presented at scientific meetings and to educators and other stakeholders. Our curators conducted outreach activities to classrooms and interested public groups, such as the Iowa Bee Keepers, and a public field day was held.

Accomplishments State Reports:

Ohio (Jourdan)

Obj 1-5: The Ornamental Plant Germplasm Center acquires, maintains, and develops germplasm of herbaceous ornamental plants.  Our primary function is to support the appropriate research and development communities by providing relevant germplasm.  In this reporting period, we received 81 germplasm requests and distributed 591 order items. Since the OPGC began distributing germplasm in 2002, 1,421 orders and 9,705 germplasm items have been distributed.  Our collection consists of 6779 accessions; 35% of the collection is available for distribution and 65% is backed up off-site; these are all stored as seeds. We received 1291 new accessions, including a large number collected through the Seeds of Success program. Our clonal collection is currently being backed up and we have 443 accessions from germplasm maintained in the greenhouse backed up in vitro at 4C or 20C for species of Begonia, Chrysanthemum, Coreopsis, Leucanthemum, Pelargonium and Phlox.   We have also managed our collection by regenerating seed of 15 accessions of species of Phlox and tested seed viability of 80 accessions last year.  Seed production has been an ongoing activity with the primarily clonal collection of Begonia; we have produced seed in about 25% of the collection and have been validating the consistency of the seedling progeny with 52 accessions being evaluated for progeny consistency this year.

Obj 4: One focus continues to be the establishment of clonal collections in vitro.  We have 95% of the Pelargonium collection (172 accessions) established in vitro at 20C, with aims to transfer the entire collection to 4C and maintain it in a 2-year transfer cycle.  We are continuing to explore strategies to reduce maintenance of the in vitro cultures by increasing the time interval between subcultures; these include low temperatures (4C) storage and osmoticum adjustment (higher levels of sucrose or addition of sorbitol).  We are also exploring control of contaminating bacteria in Begonia with a commercial control product (PPM).

In the area of seed biology, we have systematically used the Tetrazolium test for rapid assessment of seed lot viability in Phlox and have high confidence that we can bypass the lengthy germination process required for this genus and simply rely on TZ testing to assess seed lot viability.  Unfortunately, many of the locally-produced seed lots of Phlox accessions are of low quality, but there are sufficient seeds for initiation of long-term storage

Obj 6: During this reporting period, we trained 4 undergraduate students (as student workers) in the greenhouse and field operations associated with germplasm management as well as  tissue culture procedures for germplasm conservation.  We also hosted an intern from Brazil who investigated seed quality parameters in Phlox.   Our facilities and programs are regular components (tours, demonstrations, labs) of various undergraduate courses at The Ohio State University. The OPGC maintains a website dedicated to sharing information about our germplasm and research/development associated with it. We participate in the annual Cultivate’19 activity, which is the largest horticultural trade show and educational program in North America.

Iowa (Lübberstedt)

Lübberstedt lab: Doubled haploid (DH) lines are completely homozygous, excellent genetic research resources, and commonly used in commercial breeding programs. Producing DH lines is a complicated process. A simplified alternative for producing DH lines was explored, which focuses on spontaneous haploid genome doubling (SHGD). Research focuses on determining genomic regions for segregation distortion in the haploid doubling process, which is indicative of SHGD. SHGD advantages include increased pollen production and more kernels/ear produced on the haploid plant that is undergoing the doubling process to produce DH lines. BS39, a tropical population adapted to Midwest photoperiod conditions by Arnel Hallauer was crossed with an inbred line, exhibiting a high frequency of spontaneous doubling, to derive single seed descent inbred and DH lines using artificial or spontaneous haploid genome doubling, which were then genotyped. A major quantitative trait loci (QTL) on chromosome five was significantly associated with SHGD.  Capturing genetic diversity from an exotic maize population was not affected by genes controlling SHGD, as no yield penalty was observed in the presence of the major SHGD QTL. Testcross results indicate that SHGD genes will not affect the selection of higher performing lines, and that DH lines with SHGD genes are similar in performance to DH lines produced by artificial genome doubling (using colchicine) and to lines produced traditionally using single seed descent methods.

Lübberstedt received funding (as PI; Paul Scott, Kathleen Delate, Bill Tracy co-PIs) from the USDA OREI program to introduce doubled haploid (DH) technology into organic maize breeding. Key for using DH technology in organic maize breeding is the ability to double haploid genomes based on a genetic mechanism rather than artificial genome doubling based on toxic chemicals such as colchicine. The major QTL for spontaneous haploid genome doubling (SHGD) will be incorporated in different genetic backgrounds including sweet corn. First results look promising: success rates for obtaining DH lines from BS39 were higher using SHGD compared to artificial colchicine treatment-based DH line development.

Improving nitrogen use efficiency (NUE) in maize is one of the approaches to reduce N losses to the environment, as well as improve productivity in nutrient-depleted areas. Doubled haploid lines derived from exotic landraces from the Germplasm Improvement of Maize (GEM) program, backcrossed with ex-PVP inbreds PHB47 and PHZ51, were used. Root system architecture traits at seedling stage, and agronomic traits of the GEM-DH lines grown under high and low nitrogen conditions were investigated, and SNPs associated with these traits were identified.  Seedling root traits were examined because of the root system’s major role in the water and nutrient acquisition important for the plant’s survival and growth. Lines were genotyped based genotyping by sequencing. Candidate SNPs were identified that were associated with seedling root system architecture in water, and under high and low N conditions.

Kansas (Stamm)

Kansas State University has contributed to the advancement of the NPGS through utilization of germplasm stored within the system and placement of germplasm within the system for future exploitation. Specifically, the germplasm stored at the NCRPIS in Ames, IA is a critical resource for breeding canola-quality winter cultivars for the environments of the southern Great Plains.  We are developing winter canola cultivars that are released and then licensed to regional and national seed companies. During the reporting period, KSR4723 Roundup Ready winter canola was approved for foundation seed increase with a planned release in summer 2019. In addition, two cultivars, Griffin and HyCLASS225W, were granted Plant Variety Protection certification. Seed of these cultivars will be stored at the NPGS for preservation until the issued PVP certificates expire.

New cultivars continue to have a significant impact on the expansion of the southern Great Plains canola industry. Roughly 50 percent of the winter canola acres are planted to cultivars with a Kansas State University genetic component. Producers continue to employ these cultivars on their farms, improving the overall sustainability and profitability of their cropping systems through crop rotation and diversification.

Sorghum germplasm has been collected from across the globe for use in crop improvement research. Specifically, up to 800 genotypes were screened to identify herbicide-tolerant traits. Four genotypes exhibiting natural tolerance to carotenoid biosynthesis-inhibitors were identified and are being characterized to understand the mechanism of tolerance. The results from this research identified genotypes with the agronomically important traits (i.e., herbicide tolerance) for use in sorghum improvement by introgression of the trait into elite backgrounds. Availability of herbicide-tolerant technology is valuable for weed management, which is a challenging constraint in grain sorghum production throughout the U.S.

Michigan (Iezzoni)

The newly released high-yielding black bean, B18504, is also resistant to the new anthracnose Race 109. The resistance gene originated from a landrace accession from Chiapas, Mexico.  Soybean plant introductions from the USDA collection (500) were screened to identify sources of resistance to Pythium irregulare and Phytophthora sansomeana which cause soy seedling diseases, seed rot or seedling rot.  Resistance sources to both pathogens were identified and are being used as breeding parents to develop resistant varieties.

Dwarf precocious cherry rootstocks released by MSU have been evaluated for multiple years in Michigan and the Pacific Northwest and are currently licensed to commercial nurseries to enable continued testing. These dwarfing and precocity inducing rootstocks support high density production systems where fruit is harvested from the ground or from platforms resulting in reduced labor costs.  Tart cherry germplasm has been used to introgressed useful traits into sweet cherry germplasm, such as late flowering time to reduce the likelihood of crop loss from spring freeze damage.

Multi-disciplinary cucurbit research (watermelon, melon, cucumber, and squash), partially supported by the USDA-NIFA-SCRI CuCap Project, utilizes germplasm resources for disease resistance improvement.  QTLs for disease resistance and markers have been developed and breeding programs for several important diseases that threaten production were advanced by project participants. These include Fusarium wilt, gummy stem blight, powdery mildew, fruit rot caused by Phytophthora, virus diseases, and downy mildew.

Five new potato varieties were released. ‘Mackinaw’ offers long-term chip-processing quality with resistance to multiple diseases. ‘Huron Chipper’ offers excellent out-of-the-field and long-term chip processing quality, and resistance to multiple diseases.  ‘Blackberry’ is a tablestock variety with unique purple skin and deep purple flesh, appealing to specialty variety market users and consumers, and for gourmet chip processing. Others include ‘Manistee’ and ‘Saginaw Chipper’ with specific storage characteristics, disease resistance, and targeted production areas.

Maize germplasm from a variety of sources is being used to support phenotype-to-genotype and crop modeling studied of cell, leaf, plant, and canopy-level traits, and for tar spot disease resistance screening.

New chromosome-scale genomes have been constructed for two polyploidy fruit crops, cultivated blueberry and strawberry. A high density subgenome-specific genotyping arrays were designed to support screening of breeding populations and wild germplasm for markers applicable to marker-assisted breeding programs and genomic selection. Genes/genomic regions controlling fruit quality traits and disease resistance have been identified. A mapping population of  >500 individuals has been used to identify DNA-based markers for resistance to blueberry stem gall wasp  and resistant individuals. Strawberry mapping populations were used to identify saline-tolerant individuals derived from a wild germplasm source. A recombinant inbred population derived from two Petunia species (interspecific crosses) was used to identify quantitative trait loci for important plant and flower traits.

Missouri (Flint-Garcia)

Maize: The Flint-Garcia lab (USDA-ARS in Columbia MO) continues to investigate teosinte (Zea mays ssp parviglumis) and maize landraces as a source of novel and useful alleles to improve maize for a number of agronomic traits.  Previous research germplasm resources include the ‘Teosinte NILs’ population, which consists of 880 near-isogenic lines of the backcross four generation, all of which have approximately 4% of their genome segments derived from the teosinte parent, and the Nested Association Mapping (NAM) recombinant inbred lines.  In addition, they have created a new resource called the Zea Synthetic which contains the 27 maize inbred lines (25 NAM founders + B73+Mo17) and 11 Zea  parviglumis accessions (the same as the Teosinte NILs), such that the expected parentage of this population is 38% B73, 2% each other maize inbred, and 12% teosinte.  This population has been random mated 7 times prior to depositing at NCRPIS (Ames 32909).  Approximately 2000 doubled haploid lines were derived from the Zea Synthetic and will be deposited with the Maize Genetics Stock Center in winter 2019-20.

A collaborative breeding project for food corn quality traits evaluated landraces per se and as population hybrids for a large number of traits. Landraces can be viewed as similar to heirloom varieties and provide genes and traits that were eliminated from modern maize breeding pools. There has been little breeding effort in the past for non-sweet, non-popcorn food corn, and we have little knowledge about flavor components.  Wide germplasm types and target food types are being investigated, ranging from green corn to popcorn to masa-based foods. Initially 100 southeastern US and temperate heirlooms were evaluated, and currently 12 populations are being used in an S1 selection project to improve basic agronomic traits. Landraces and derived crosses are being evaluated for adaptation, agronomic traits, starch/oil/protein content, flavor and aroma compounds, and their applications for use in tortillas, popcorn, and other culinary uses.

New York (Smith)

For objective 2 (collect and maintain plant genetic resources of dedicated crops and their crop wild relatives, evaluate and enhance this germplasm), our project focused on corn evaluation and enhancement.  At Cornell, we used USDA collections of public corn inbreds from historic breeding programs and off-patent inbreds, and collections of exotic corn germplasm as genetic resources to build pest resistance into U.S.-adapted field and sweet corn backgrounds and diversify high-yielding, US-adapted field corn germplasm.  In summer 2019, we advanced breeding populations being selected for gray leaf spot resistance, anthracnose leaf blight and stalk rot resistance, and European corn borer resistance. We advanced a multiple disease resistant sweet corn breeding effort based on selection of breeding lines that had shown resistance to northern leaf blight, anthracnose leaf blight, and Stewart’s wilt. An undergraduate researcher initiatied a breeding project focused on increasing tillering capacity using eight accessions from the USDA germplasm collection, to study whether highly tillering types could offer weed competition benefits in organic systems.

For objective 6 (educate students, scientists and the general public regarding plant germplasm issues), a breeding nursery visit for graduate students from Cornell University, lectures to a number of on-campus classes and to a group of visiting undergraduate agriculture interns, and conversations with hundreds of visitors viewing our display at New York's Empire Farm Days all emphasized the importance of genetic resources as the raw material by which plant breeding can continue addressing the needs and issues arising in our agricultural and food systems.  In addition, educational talks addressed issues and concerns about genetically engineered crop varieties. In this past project year, five talks were presented on this topic, which reached over 250 listeners in person and many additional people via video recordings, news articles, and web-based media. These presentations emphasized education and explicitly did not promote a particular viewpoint on this very polarizing topic. Targeted learning outcomes included what genetic engineering is, how it fits within the context of long-term crop selection/improvement and conservation efforts, how extensively genetically engineered varieties are being grown, where they make their way into our food, and what our scientific understanding is to date regarding the risks and benefits of genetically engineered crops.

 Five talks about genetically engineered crops were presented to public audiences and four lectures were given to Cornell undergraduate and graduate student classes. These educational talks reached more than 680 people with educational information (not advocacy) about genetically engineered crops.

New York (Gore)

Nutritional deficiencies are a worldwide problem and affect mainly children, women, and adults over 65 years. Although these deficiencies are far less prevalent in developed nations, surprisingly large proportions of the US population still do not obtain the daily recommended amount of several nutrients, particularly iron and zinc. Given that sweet corn is the third most commonly consumed vegetable in the US and previous work has shown it to possess high variability for these compounds, we assessed natural variation for mineral levels in fresh kernels of a sweet corn association panel. A genome-wide association study of the fresh kernel ionome identified candidate genes associated with levels of iron and zinc (nas5, nicotianamine synthase), as well as cadmium (hma3, heavy metal ATPase). Within-location analysis showed associations for nickel and molybdenum in NY and for calcium in WI, and candidate genes include ras2 (Ras-like GTPase) for calcium and ptr2 (peptide transporter) for nickel. We also developed whole-genome prediction models for these minerals that had with moderate predictive abilities, which may now be used in a genomics-assisted breeding program for developing sweet corn lines with improved fresh kernel element composition. Given that associations observed for iron and zinc were at different regions of the genome than for cadmium, and the low genetic correlation between both groups, breeders could use these models to concurrently select for sweet corn with increased iron and zinc but low cadmium for human nutrition.

Recent advances in quantitative genetic approaches combined with next-generation sequencing and field-based high-throughput phenotyping tools could help to provide insight into the genetic basis of natural variation for the response of photosynthesis in C4 plants to the local growing environment. A sweet corn association panel was genotyped by genotyping-by-sequencing and measured the six fluorescence-based parameters (ΦII, NPQ(T), ΦNO, LEF, qL, F′v/F′m) related to photosystem II (PSII) activity on the primary ear leaf of sweet corn plants at flowering in replicated field trials in two years. Moderate to high genetic correlations were detected among majority of the PSII phenotypes. We leveraged these correlations using multivariate genome-wide association study (GWAS). A total of 10 unique SNPs were identified to be significantly associated with PSII phenotypes at a genome-wide false-discovery rate of 10%. Notably, the photosystem I reaction center subunit V gene on chromosome 7 was associated with the phenotype pairs of ΦII and ΦNO, and LEF and qL. A candidate gene encoding an isoform of sucrose synthase underpinned the GWAS signals associated with the phenotype pair of ΦNO and qL on chromosome 10.

Leaf length, leaf width and leaf angle, important components of leaf architecture, influence canopy morphology and photosynthetic efficiency and, as a result, overall crop yield. However, no research on leaf architecture of sweet corn has been published to our knowledge. With a constructed sweet corn association panel, we dissected the genetic basis of leaf length, leaf width, upper leaf angle and ear leaf angle. Extensive and highly heritable variation was observed for these four leaf architecture related traits. From a genome-wide association study, we identified a total of 59 significant marker-trait associations (MTAs) for the 4 traits. Of the associations, 3 MTAs had significant overlap with known QTL associated with leaf architecture in maize. Furthermore, 5 candidate genes identified for these four traits had annotations suggesting their potential role in leaf development. These results enhance our understanding of the genetic basis of leaf architecture in sweet corn and pave the way for exploration of underlying molecular mechanisms and manipulation of leaf architecture in breeding practices.

High-throughput image-phenotyping promises to accelerate the rate of genetic improvement in plant breeding through varietal selections informed by longitudinal growth models. To facilitate routine analyses and to drive breeding decisions, data integration is critical for effective management of germplasm, field experiment design, phenotyping, tissue sampling, genotyping, aerial-phenotyping campaigns, image files, and geo-spatial information. To this end, ImageBreed provides a novel software solution for end-to-end image-based phenotyping integrated into the Breedbase plant breeding system. ImageBreed provides open-source orthophotomosaic construction for raw image-captures. Additionally, previously assembled raster images can be uploaded, facilitating the use of any camera instrument granted the image meets defined spectral category constraints. A web-database interface streamlines assignment of plot-polygon images from the orthophotomosaic to the field experiment design. Image processes spanning Fourier transform filtering, thresholding, and vegetation index masking are applied to reduce noise in extracted phenotypes. Summary-statistic phenotypic values are extracted for every observed plot-polygon image using a structured ontology. Leveraging the Breedbase system on which ImageBreed is built, plot-polygon images are queryable against genotypic, phenotypic, and experimental design information for training of machine learning models and for driving breeding decisions in varietal advancement. ImageBreed is publicly available at http://imagebreed.org and built on the open-source Breedbase system (https://github.com/solgenomics/sgn); all image processing scripts are available at https://github.com/solgenomics/DroneImageScripts and via a Docker image. All data deposited in http://imagebreed.org are publicly available for longitudinal model training and for driving future breeding decisions. This work with conducted in collaboration with Nicolas Morales (Robbins Lab), Nicholas Santantonio (Robbins Lab), Kelly Robbins, and Lukas Mueller at Cornell University.

North Dakota (Johnson)

North Dakota crop production includes more than 20 crops that provide agronomic and economic diversity to the state’s producers and value-added agricultural industries that include food, feed, fiber, and biofuel products. Eleven of these crops have active plant breeding programs in the Dept. of Plant Sciences at North Dakota State University and include hard red spring wheat (Triticum aestivum L.), durum wheat (Triticum turgidum L.), winter wheat (Triticum aestivum L.), barley (Horedum vulgare L.), oats (Avena sativa L.), canola (Brassica napus L.), dry bean (Phaseolus vulgaris L.), field pea (Pisum sativum L.), flax (Linum uistatissimum L), soybean (Glycine max (L.) Merr.), and potato (Solanum tuberosum L.). These plant breeding programs utilize genetic resources to increase crop performance through improved pest resistance and stress tolerance and from consistent varietal performance under fluctuating growing conditions associated with more variable weather patterns.

In addition to active plant breeding programs new crops are continually screened for adaptation potential to the region. Approximately 55 new crops have been screened for adaptation to North Dakota and surround region since 1989 with most exhibiting agronomic deficiencies (seed dormancy, seed shatter, low seed production, late maturity, and harvestability issues) that prevented commercialization without considerable plant breeding improvement. Several new crop screenings have resulted in commercial production and include grain sorghum (Sorghum bicolor (L.) Moench), Ethiopian mustard (Brassica carinata L.), camelina (Camelina sativa L.), and industrial hemp (Cannabis sativa L.).

Field pennycress (Thlaspi arvense L.) is adapted to North Dakota growing conditions and has been included in relay cropping systems studies with corn and soybean as a winter annual cash grain industrial oilseed. Developing commercial pennycress production has been ongoing in Illinois for nearly 10 years as a winter annual established in the fall and harvested the following spring before soybean planting. Shortness of the growing season in North Dakota doesn’t allow this cropping approach. Results from spring relay seeding soybean into established pennycress resulted in soybean yield reduction compared with sole crop soybean. The harvested pennycress grain value was not sufficient to offset the loss in relayed soybean yield.

Industrial hemp production is gaining momentum in North Dakota and nationally as a new-old crop with initial production in 2015/2016 primarily for grain and derived food products. Hemp stalk fiber applications are numerous ranging from textiles to construction materials, but the industry lacks processing facilities which need logistics close to production areas to be economical to producers and processors. Heightened interest and production of hemp for CBD in 2019 spans across the entire U.S. due to high crop/product values when compared to hemp grown for grain/fiber or other traditional and high-value crops. Germplasm management at the national level would be helpful to industrial hemp commercialization.

Oregon (Liston)

Objective: Characterize plant germplasm using a combination of molecular and traditional techniques and utilize modern plant genetic techniques to help manage plant germplasm.

Findings: The cultivated strawberry (Fragaria ×ananassa) is an octoploid, and the identity of its four subgenomes has long been a mystery. The 2019 publication of the first chromosome-scale genome assembly of the octoploid strawberry Fragaria ×ananassa cultivar ‘Camarosa’ represents a significant scientific advance and provides a foundational resource for this important cultivated plant. The authors of the genome publication presented a novel hypothesis: each subgenome originated from a different extant diploid progenitor, and the hexaploid species Fragaria moschata was a direct ancestor. We reanalyzed the four octoploid subgenomes in a phylogenomic context and our results support only two extant diploid progenitors; we also found no support for F. moschata as a direct ancestor. We argue that the tree-searching algorithm used in the genome publication is potentially biased against accepting extinct or unsampled progenitors, a weakness that impacts the resolution of polyploid genomic architecture. Correctly identifying the diploid progenitors of polyploid plants is important for understanding and predicting their responses to climate change and associated environmental stress.

South Dakota (Caffe Treml)

Researchers at South Dakota State University participated in the NC-7 Hatch Multi-state project by characterizing and utilizing plant genetic resources for crop improvement. Genetic resources were characterized for traits associated with production challenges in South Dakota and the region through diverse research projects.

Caffe Treml lab: Dreschslera avenae is a fungal pathogen causing leaf spot disease in oats. This disease has been observed on oat in US as well as in other countries throughout the world. The leaf necrosis can result in a reduction in grain yield. A panel of 313 oat breeding lines from US oat breeding programs was phenotyped in the greenhouse for susceptibility to Dreschslera avenae. Genotyping data was accessed through the T3/Oat database. A total of 5 QTLs associated with resistance to Dreschslera avenae were identified. Twenty-one breeding lines exhibited some resistance to leaf spot disease caused by Dreschslera avenae and could be used as sources of resistance in crossing.

Byamukama lab: Eight soybean PI lines were used for determining soybean cyst nematode virulence phenotypes (HG types) occurring in South Dakota. Two hundred and fifty PI lines were used in the screening for Phyophthora sojae resistance.

Mathew lab: Twenty-five (25) soybean accessions belonging to maturity group I (MG-I) that are popular in the upper Midwest were screened for resistance to two fungi – Fusarium graminearum and Fusarium proliferatum – that cause root disease of soybean. Among the accessions, PI361090 was identified to be significantly less susceptible to F. graminearum and F. proliferatum compared to the checks, ‘Asgrow 1835’ and ‘Williams 82’.  PI361090 may be a useful source of resistance for breeders to develop soybean cultivars with resistance to root rot caused by F. graminearum and F. proliferatum.

Two hundred and forty-seven (247) accessions were screened for their resistance to F. graminearum. Eight soybean accessions (PI437949, PI438292, PI612761A, PI438094B, PI567301B, PI408309, PI361090 and P188788) were observed to be significantly less susceptible to F.graminearum when compared to the susceptible checks, Williams 82 and Asgrow 1835. The eight accessions may be used in breeding programs as sources of resistance to F.graminearum for advance screening and development of resistant soybean cultivars. In addition, the data is used by the soybean breeding program at Iowa State University to identify single nucleotide polymorphism markers associated with resistance to F. graminearum.

Forty-nine accessions were screened for resistance to Phomopsis stem canker using a representative isolate of the causal fungi - Diaporthe helianthi and D. gulyae. Among the 49 accessions, 13 and four accessions were less susceptible to D. helianthi (PI 507894, PI 507911, PI 509064, PI 531366, PI 531389, PI 549002, PI 552939, PI 560145, PI 599765, PI 633748, PI 650359, PI 664179, and PI 664232) and D. gulyae ((PI 552939, PI 561918, PI 618725, and PI 632342), respectively, compared with the susceptible confection USDA inbred ‘HA 288’. These plant introductions can be useful source of resistance for sunflower breeders to develop resistant commercial hybrids. In addition, PI 561918 is currently used in the sunflower breeding program at USDA-ARS, Fargo, ND to develop breeding lines with disease resistance.

Sehgal lab: Wheat germplasm was identified with novel sources of resistance to spot blotch, tan spot, fusarium head blight, and bacterial leaf streak. Resistant QTLs were identified through GWAS. Novel sources of resistance to tan spot in cultivated rye were identified, and resistant QTLs through GWAS. 

Li lab:  Alien gene transfer is an effective approach for wheat germplasm enhancement. Thinopyrum junceiforme, also known as sea wheatgrass (SWG), is a distant relative of wheat and a relatively untapped source for wheat improvement. A complete amphiploid (has diploid sets of chromosomes originating from two different species), 13G819, between emmer wheat and SWG was developed for the first time. The amphiploid 13G819 and its emmer wheat parent were evaluated for their tolerance to various abiotic and biotic stress. Compared to its emmer wheat parent, the amphiploid showed high tolerance to waterlogging, manganese toxicity, salinity, low nitrogen, and possibly to heat as well. The amphiploid 13G819 is also highly resistant to the wheat streak mosaic virus, Fusarium head blight, and wheat stem sawflies. Impact: Sea wheatgrass can be used as source for improving wheat resistance to diseases and insects and tolerance to abiotic stress.