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Hemp seed protein isolates (HPI) were extracted from the seeds of seven commercial hemp cultivars, a Cornell breeding line, and a commercial hemp heart product. The composition and functional properties of the resulting HPI were investigated. HPI were of high protein purity >96% and contained various ratios of the major protein classes edestin, vicilin, and albumin, depending on the source. Protein solubility varied across HPI, and there was a positive correlation between greater levels of vicilin and albumin and improved solubility. The isoelectric points of HPI ranged from 5.50 to 5.94 but did not show significant effects associated with major protein class ratio. Significant differences in HPI foam capacity (52.9–84.9%), foam stability (68.1–89.4%), water holding capacity (0.83–1.05 g water/g protein isolate), and oil holding capacity (1.28–1.81 g oil/g protein isolate) were observed. In general, the emulsions generated from HPI performed poorly in terms of emulsifying activity, stability, and emulsion particle size. The ratio of edestin, vicilin, and albumin was found to play a major role in HPI functionality, suggesting that certain hemp cultivars may be better suited for generating protein ingredients that can functionalize plant-based foods.

Hemp (Cannabis sativaL.) is an extraordinarily versatile crop, with applications ranging from medicinal compounds to seed oil and fibre products.Cannabis sativais a short-day plant, and its flowering is tightly controlled by photoperiod. However, substantial genetic variation exists for photoperiod sensitivity inC. sativa,and photoperiod-insensitive (“autoflower”) cultivars are available.Using a bi-parental mapping population and bulked segregant analysis, we identifiedAutoflower2, a 0.5 Mbp locus significantly associated with photoperiod-insensitive flowering in hemp.Autoflower2contains an ortholog of the central flowering time regulatorFLOWERING LOCUS T(FT) fromArabidopsis thalianawhich we termedCsFT1. Extensive sequence divergence between alleles ofCsFT1was identified between photoperiod-sensitive and insensitive cultivars ofC. sativa, including a duplication ofCsFT1and sequence differences especially in introns. Genotyping of several mapping populations and a diversity panel confirmed a strong correlation betweenCsFT1alleles and photoperiod response as well as affirming that at least two independent loci for this agriculturally important trait,Autoflower1andAutoflower2, exist in theC. sativagene pool.This study reveals the multiple independent origins of photoperiod insensitivity inC. sativa,supporting the likelihood of a complex domestication history in this species. By integrating the genetic relaxation of photoperiod sensitivity into novelC. sativacultivars, expansion to higher latitudes will be permitted, thus allowing the full potential of this versatile crop to be reached.

The Salicaceae family is of growing interest in the study of dioecy in plants because the sex determination region (SDR) has been shown to be highly dynamic, with differing locations and heterogametic systems between species. Without the ability to transform and regenerateSalixin tissue culture, previous studies investigating the mechanisms regulating sex in the genusSalixhave been limited to genome resequencing and differential gene expression, which are mostly descriptive in nature, and functional validation of candidate sex determination genes has not yet been conducted. Here we used Arabidopsis to functionally characterize a suite of previously identified candidate genes involved in sex determination and sex dimorphism in the bioenergy shrub willowSalix purpurea. Six candidate master regulator genes for sex determination were heterologously expressed in Arabidopsis, followed by floral proteome analysis. In addition, 11 transcription factors with predicted roles in mediating sex dimorphism downstream of the SDR were tested using DAP-Seq in both male and femaleS. purpureaDNA. The results of this study provide further evidence to support models for the roles ofARR17andGATA15as master regulator genes of sex determination inS. purpurea, contributing to a regulatory system that is notably different from that of its sister genusPopulus. Evidence was also obtained for the roles of two transcription factors, anAP2/ERFfamily gene and a homeodomain-like transcription factor, in downstream regulation of sex dimorphism.

Hemp (Cannabis sativaL.) is a primarily short-day crop grown for grain, fiber, and secondary metabolites. Although terminal flowering of most non-domesticated hemp is regarded as photoperiod sensitive, limited germplasm is available for the development of day-neutral hemp. Day-neutral plants experience flower maturation independently of the short-day photoperiod cue which is typically triggered by photoperiods of less than 14 hours. The day-neutral trait is the subject of increased commercial interest for the purpose of breeding varieties with accelerated flowering time or cultivars that do not require labor- and cost-intensive light deprivation production systems. Genetic markers for the photoperiodic response would help breeders make early selection in the design of suitable cultivars for specific environments and cultivation calendars. Limited refereed information has been produced regarding the genetic regulation of photoperiodism inC. sativa. A population of 318 F2 individuals segregating for day-neutral flowering was developed, phenotyped, and genotyped. Genome-wide association analysis identified markers associated with the day-neutral trait indicating that a single recessive gene controlling photoperiod sensitivity is located within a large region of Chromosome 1. Flanking region sequence data of linked SNP markers was used in the development and validation of a TaqMan-based qPCR assay for the day-neutral trait. A genetic linkage map was produced, and QTL mapping identified two additional markers on Chromosome 1. Candidate genes,TARGET OF EARLY ACTIVATION TAGGED (TOE)/APETALA2 (AP2), andPSEUDO-RESPONSE REGULATOR 3 (PRR3), may work together to impact phase transition and photoperiodic flowering respectively and have key domains that are disrupted in day-neutral plants.

Poplar and willow species in the Salicaceae are dioecious, yet have been shown to use different sex determination systems located on different chromosomes. Willows in the subgenus Vetrix are interesting for comparative studies of sex determination systems, yet genomic resources for these species are still quite limited. Only a few annotated reference genome assemblies are available, despite many species in use in breeding programs. Here we present de novo assemblies and annotations of 11 shrub willow genomes from six species. Copy number variation of candidate sex determination genes within each genome was characterized and revealed remarkable differences in putative master regulator gene duplication and deletion. We also analyzed copy number and expression of candidate genes involved in floral secondary metabolism, and identified substantial variation across genotypes, which can be used for parental selection in breeding programs. Lastly, we report on a genotype that produces only female descendants and identified gene presence/absence variation in the mitochondrial genome that may be responsible for this unusual inheritance. Published version

Shrub willows (Salix spp.) are emerging as a viable lignocellulosic, second-generation bioenergy crop with many growth characteristics favorable for marginal lands in New York State and surrounding areas. Willow rust, caused by members of the genus Melampsora, is the most limiting disease of shrub willow in this region and remains extremely understudied. In this study, genetic diversity, genetic structure, and pathogen clonality were examined in Melampsora americana over two growing seasons via genotyping-by-sequencing to identify single-nucleotide polymorphism markers. In conjunction with this project, a reference genome of rust isolate R15-033-03 was generated to aid in variant discovery. Sampling between years allowed regional and site-specific investigation into population dynamics, in the context of both wild and cultivated hosts within high-density plantings. This work revealed that this pathogen is largely panmictic over the sampled areas, with few sites showing moderate genetic differentiation. These data support the hypothesis of sexual recombination between growing seasons because no genotype persisted across the two years of sampling. Additionally, clonality was determined as a driver of pathogen populations within cultivated fields and single shrubs; however, there is also evidence of high genetic diversity of rust isolates in all settings. This work provides a framework for M. americana population structure in the Great Lakes region, providing crucial information that can aid in future resistance breeding efforts.

Despite the economic, ecological, and scientific importance of the generaPopulusL. (poplars, cottonwoods, and aspens) andSalixL. Salicaceae (willows), we know little about the sources of differences in species diversity between the genera and of the phylogenetic conflict that often confounds estimating phylogenetic trees.Salixsubgenera and sections, in particular, have been difficult to classify, with one recent attempt termed a ‘spectacular failure’ due to a speculated radiation of the subgeneraVetrixandChamaetia. Here we use targeted sequence capture to understand the evolutionary history of this portion of the Salicaceae plant family. Our phylogenetic hypothesis was based on 787 gene regions and identified extensive phylogenetic conflict among genes. Our analysis supported some previously described subgeneric relationships and confirmed polyphyly of others. Using an fbranchanalysis we identified several cases of hybridization in deep branches of the phylogeny, which likely contributed to discordance among gene trees. In addition, we identified a rapid increase in diversification rate near the origination of theVetrix-Chamaetiaclade inSalix. This region of the tree coincided with several nodes that lacked strong statistical support, indicating a possible increase in incomplete lineage sorting due to rapid diversification. The extraordinary level of both recent and ancient hybridization in bothPopulusandSalixhave played important roles in the diversification and diversity in these two genera.Supplementary data files will be provided by request tomatt.olson@ttu.edu

Poplar and willow species in the Salicaceae are dioecious, yet have been shown to use different sex determination systems located on different chromosomes. Willows in the section Vetrix are interesting for comparative studies of sex determination systems, yet genomic resources for these species are still quite limited. Only a few annotated reference genome assemblies are available, despite many species in use in breeding programs. Here we present de novo assemblies and annotations of 11 shrub willow genomes from six species. Copy number variation of candidate sex determination genes within each genome was characterized and revealed remarkable differences in putative master regulator gene duplication and deletion. We also analyzed copy number and expression of candidate genes involved in floral secondary metabolism, and identified substantial variation across genotypes, which can be used for parental selection in breeding programs. Lastly, we report on a genotype that produces only female descendants and identified gene presence/absence variation in the mitochondrial genome that may be responsible for this unusual inheritance.

Cannabis sativais cultivated for multiple uses including the production of cannabinoids. In developing improved production systems for high-cannabinoid cultivars, scientists and cultivators must consider the optimization of complex and interacting sets of morphological, phenological, and biochemical traits, which have historically been shaped by natural and anthropogenic selection. Determining factors that modulate cannabinoid variation within and among genotypes is fundamental to developing efficient production systems and understanding the ecological significance of cannabinoids. Thirty-two high-cannabinoid hemp cultivars were characterized for traits including flowering date and shoot-tip cannabinoid concentration.Additionally, a set of plant architecture traits, as well as wet, dry, and stripped inflorescence biomass were measured at harvest. One plant per plot was partitioned post-harvest to quantify intra-plant variation in inflorescence biomass production and cannabinoid concentration. Some cultivars showed intra-plant variation in cannabinoid concentration, while many had a consistent concentration regardless of canopy position. There was both intra- and inter-cultivar variation in architecture that correlated with intra-plant distribution of inflorescence biomass, and concentration of cannabinoids sampled from various positions within a plant. These relationships among morphological and biochemical traits will inform future decisions by cultivators, regulators, and plant breeders as well as our broader understanding of intra-plant variation of specialized biochemicals.HighlightIn-season hemp plant architecture measurements can predict post-harvest traits related to the distribution of biomass and concentration of cannabinoids.

Shrub willows (

Automation has been introduced into variant interpretation, but it is not known how automated variant interpretation performs on a stand-alone basis. The purpose of this study was to evaluate a fully automated computerized approach.We reviewed all variants encountered in a set of carrier screening panels over a 1-year interval. Observed variants with high-confidence ClinVar interpretations were included in the analysis; those without high-confidence ClinVar entries were excluded.Discrepancy rates between automated interpretations and high-confidence ClinVar entries were analyzed. Of the variants interpreted as positive (likely pathogenic or pathogenic) based on ClinVar information, 22.6% were classified as negative (variants of uncertain significance, likely benign or benign) variants by the automated method. Of the ClinVar negative variants, 1.7% were classified as positive by the automated software. On a per-case basis, which accounts for variant frequency, 63.4% of cases with a ClinVar high-confidence positive variant were classified as negative by the automated method.While automation in genetic variant interpretation holds promise, there is still a need for manual review of the output. Additional validation of automated variant interpretation methods should be conducted.

Hemp (Cannabis sativa) is a burgeoning crop, but research‐based information about genetic and environmental effects of cannabinoid production is limited and will be essential for expanded cultivation. There are limited data available about the effect of environmental stressors on cannabinoid content, particularly for tetrahydrocannabinol (THC) in high‐cannabidiol (CBD) hemp. To address this, five stress treatments were applied in a replicated field trial with three high‐CBD hemp cultivars and cannabinoid content was assayed over a 3‐week time‐course spanning floral maturation. Cannabinoid production in terminal inflorescence shoot tip samples of three cultivars was measured under stress imposed by flooding, ethephon, powdery mildew, herbicide, and physical wounding in a split plot design. The treatments had limited effects on cannabinoid levels, with the exception of herbicide treatment which resulted in decreased cannabinoid content. Notably, there was no evidence that any of these stresses caused THC concentration or the ratio of THC to CBD to increase at harvest.

PREMISE The evolution of sex chromosomes is driven by sexual dimorphism, yet it can be challenging to document sexually dimorphic traits in dioecious plant species. At the genetic level, sexual dimorphism can be identified through sequence variation between females and males associated with sexually antagonistic traits and different fitness optima. This study aims to examine sexual dimorphism for 26 traits in three populations of Salix purpurea (a diversity panel and F1 and F2 populations) and determine the effect of the traits on biomass yield, a key trait in Salix bioenergy crops across multiple years, locations, and under manipulated growth conditions. METHODS Sexual dimorphism was evaluated for morphological, phenological, physiological, and wood composition traits in a diversity panel of unrelated S. purpurea accessions and in full-sib F1 and F2 families produced through controlled cross pollinations and grown in replicated field trials. RESULTS We observed sexual dimorphism in the timing of development for several traits that were highly predictive of biomass yield across three populations of S. purpurea. Across all populations and years surveyed, males had significantly shallower branching angle. Male plants highly predictive of biomass yield across three populations of S. purpurea also accumulated more nitrogen under fertilizer amendment as measured by SPAD in the diversity panel and had greater susceptibility to the rust fungus Melampsora americana in the F2 family. Allometric modelling of biomass yield showed an effect of sex and of location on the interaction between yield and stem height. CONCLUSIONS These results provide evidence of sexual dimorphism for certain traits in S. purpurea that may be involved in sex chromosome evolution.

Hemp (

Flowering time is an important trait for all major market classes of hemp (Cannabis sativa), affecting yields and quality of grain, fiber, and cannabinoids. C. sativa is usually considered a short-day plant, flowering once night length reaches a critical threshold. Variations in flowering time within and across cultivars in outdoor grown populations have been previously identified, likely corresponding to genetic differences in this critical night length. Further, some C. sativa are photoperiod insensitive, colloquially referred to as “autoflowering.” This trait has anecdotally been described as a simple recessive trait with major impacts on phenology and yield. In this work, the locus responsible for the “autoflower” trait (Autoflower1), as well as a major-effect flowering time locus, Early1, were mapped using bulked segregant analysis. Breeder-friendly high-throughput molecular marker assays were subsequently developed for both loci. Also detailed are the flowering responses of diverse cultivars grown in continuous light and the result of crossing two photoperiod insensitive cultivars of differing pedigree.

Melampsora rust is a devastating disease of shrub willow in North America. Previous work has identified Melampsora paradoxa as one of two identified rust species in New York State that infect Salix purpurea and other important Salix host species, however little is known about the population of this rust species in this region. Genotyping-by-sequencing was used to identify single nucleotide polymorphisms (SNPs) and assess population diversity of M. paradoxa isolates collected from three Salix breeding populations in Geneva, NY between 2015 and 2020. Statistical analyses of SNP revealed that all isolates collected were clonally derived even though they were collected across years. In 2020, isolates were collected from stem infections where uredospore pustules were observed, and these isolates were also identical to M. paradoxa collected in previous seasons. These data suggest that M. paradoxa sampled across multiple years overwintered and reproduced asexually and that stem infection is a possible mechanism for overwintering, both of which are novel findings for this rust species. Additionally, field disease ratings were conducted on a S. purpurea × S. suchowensis F1 breeding population with high disease severity, enabling the discovery of QTL for resistance on chromosomes 1 and 19. Lastly, Colletotrichum salicis was frequently associated with stem rust and may play a role in M. paradoxa stem infection. Together, this work is the first substantial exploration into M. paradoxa population biology, stem infection, and host resistance in Salix.

Given the dramatic rise in high‐cannabinoid hemp (Cannabis sativa L.) production in the last decade, there is an increasingly urgent need to characterize available germplasm and develop knowledge to accelerate the breeding of uniform and stable cultivars. Despite persistent cultivation of hemp cultivars for grain and or fiber around the world, the diversity and genetic underpinning of key traits for breeding and cultivation are poorly understood. For 30 high‐cannabidiol hemp cultivars replicated on two field sites, we sought to evaluate yield, agronomic performance, and disease resistance while also conducting a detailed study of cannabinoid accumulation over the course of floral maturation. We observed significant variation in both within and among cultivars. During the growing season, the plants clustered into five groups by growth rate and varied in flowering time from photoperiod insensitive to photoperiod sensitive with very short critical photoperiods. Based on the observed ratio of total potential cannabidiol (CBD) to total potential tetrahydrocannabinol (THC), there was segregation for cannabinoid chemotype in some seeded cultivar populations. Analysis of cannabichromene (CBC) production revealed that some cultivars had a discretely lower CBD:CBC ratio than the others. There was a continuous range of powdery mildew severity by cultivar, with one that had little to no observed powdery mildew suggesting it might have genetic resistance. Biomass production at harvest was strongly influenced by location and cultivar, and there was variation by cultivar in the relative cannabinoid production in shoot tip samples compared with whole plant samples. While our results provide preliminary guidance regarding relative performance of current cultivars, our analyses indicate a need for additional hemp breeding to provide stable, uniform, and legally compliant cultivars with improved disease resistance and flowering times optimized for the latitudes of different growing locations.