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Flavor is essential to consumer preference of foods and is an increasing focus of plant breeding programs. In fruit crops, identifying genes underlying volatile organic compounds has great promise to accelerate flavor improvement, but polyploidy and heterozygosity in many species have slowed progress. Here we use octoploid cultivated strawberry to demonstrate how genomic heterozygosity, transcriptomic intricacy and fruit metabolomic diversity can be treated as strengths and leveraged to uncover fruit flavor genes and their regulatory elements. Multi-omics datasets were generated including an expression quantitative trait loci map with 196 diverse breeding lines, haplotype-phased genomes of a highly-flavored breeding selection, a genome-wide structural variant map using five haplotypes, and volatile genome-wide association study (GWAS) withgt; 300 individuals. Overlaying regulatory elements, structural variants and GWAS-linked allele-specific expression of numerous genes to variation in volatile compounds important to flavor. In one example, the functional role of anthranilate synthase alpha subunit 1 in methyl anthranilate biosynthesis was supported via fruit transient gene expression assays. These results demonstrate a framework for flavor gene discovery in fruit crops and a pathway to molecular breeding of cultivars with complex and desirable flavor.

Magnesium chelatase (MgCh) catalyzes the insertion of magnesium into protoporphyrin IX, a vital step in chlorophyll (Chl) biogenesis. The enzyme consists of 3 subunits, MgCh I subunit (CHLI), MgCh D subunit (CHLD), and MgCh H subunit (CHLH). The CHLI subunit is an ATPase that mediates catalysis. Previous studies on CHLI have mainly focused on model plant species, and its functions in other species have not been well described, especially with regard to leaf coloration and metabolism. In this study, we identified and characterized a CHLI mutant in strawberry species Fragaria pentaphylla. The mutant, noted as p240, exhibits yellow–green leaves and a low Chl level. RNA-Seq identified a mutation in the 186th amino acid of the CHLI subunit, a base conserved in most photosynthetic organisms. Transient transformation of wild-type CHLI into p240 leaves complemented the mutant phenotype. Further mutants generated from RNA-interference (RNAi) and CRISPR/Cas9 gene editing recapitulated the mutant phenotype. Notably, heterozygous chli mutants accumulated more Chl under low light conditions compared with high light conditions. Metabolite analysis of null mutants under high light conditions revealed substantial changes in both nitrogen and carbon metabolism. Further analysis indicated that mutation in Glu186 of CHLI does not affect its subcellular localization nor the interaction between CHLI and CHLD. However, intramolecular interactions were impaired, leading to reduced ATPase and MgCh activity. These findings demonstrate that Glu186 plays a key role in enzyme function, affecting leaf coloration via the formation of the hexameric ring itself, and that manipulation of CHLI may be a means to improve strawberry plant fitness and photosynthetic efficiency under low light conditions.

Guayusa (Ilex guayusa) is an endemic plant from the Amazon with potential medicinal applications. Indigenous people are familiar with such applications and use guayusa based on ancestral knowledge. There is a growing interest in guayusa-based products in urban areas of Ecuador and internationally. The supply cannot meet the demand. Currently, traditional practices are used for guayusa growth and the potential use of the protected forest is foreseen. This work describes a protocol for the in vitro propagation of guayusa, a sustainable solution to generate high quality plants in reduced space. Stakes obtained from stems were used as explants. Chemical sterilization with ethanol and sodium hypochlorite resulted in 100% surface-sterilized stakes. The growth medium mWPM resulted in favorable outcomes regarding shoot development and elongation, as well as rooting. Supplementation with activated charcoal resulted in reduced browning, only 10% of the shoots presented necrosis during the elongation phase. More than two thirds of shoots were able to develop roots spontaneously. Medium supplementation with the auxin indole-3-butyric acid, IBA, may be considered when rooting does not occur spontaneously. Acclimatization was performed in soil. The protocol was tested under different light spectra, revealing that guayusa growth is affected by light quality. The photobiology of this shade tolerant plant requires further characterization, but the data uncovered a potential role for green and far-red light in root development. Guayusa was propagated on mWPM medium supplemented with activated charcoal. Spontaneous root development occurred in most shoots. Light quality affected plant development, green and far-red light could influence root growth.

In the United States, adult public perception of genetic modification has been well documented in the domain of agriculture and food; however, recent international news on gene editing in medical applications may present new challenges for science communicators who seek to proactively share benefits of emerging gene editing technology. While research traditionally considers perceptions of agricultural and medical applications separately, gene editing may bridge the gap between the two domains. We find that when asked about thoughts regarding gene editing, adult focus groups discussed medical applications more frequently and extensively than agricultural applications. Although, when examining the length of discussion about specific topics, designer babies, cures for disease, and food were discussed at similar lengths. Understanding audiences' current perceptions of the technology is the first step in shaping strategic communication efforts to inform public opinion. A proper understanding of the benefits and risks of new technology is central to its application.

Consumers consistently note that there is room for improvement in the flavor of commercial strawberries. Fruit flavor and aroma are affected by both genetics and environment. This work tests the hypothesis that sensory quality may be manipulated using postharvest light treatments. Individual detached fruits representing two different cultivars received a 24-hr treatment of 100 µmol m-2 s-1 blue LED light while the control was kept in complete darkness. Following treatment, samples were analyzed for flavor volatiles, sugars, acids, firmness, and sensory differences in human trials. Fruits were rated for overall liking, texture, sweetness, sourness, and overall strawberry flavor intensity (OSFI) on the sensory and hedonic versions of the global intensity scale (GIS). A positive treatment effect was observed for "Strawberry Festival" fruit for the overall liking rating. A triangle test revealed a significant treatment effect, as light-treated fruit tested higher in many flavor volatiles including those known to contribute to sweetness in strawberries. Levels of several volatiles were consistently higher in the treated fruit across all four harvests: acetic acid hexyl ester, butanoic acid octyl ester, methyl isovalerate, and pentanoic acid ethyl ester. The results show that postharvest light treatment can be used to modulate sensory quality of fruit, perhaps offering a means to complement genetic efforts in fruit flavor and aroma improvement. PRACTICAL APPLICATION: The results indicate that it may be possible to increase the sensory quality of strawberry fruits using an inexpensive and noninvasive light treatment. Light may be applied during transport or storage to improve fruit quality. This concept could also be extended into other realms of storage, such as residential and commercial refrigeration, further increasing the quality impact of the approach.

Summary Plant architecture is central in determining crop yield. In the short‐day species strawberry, a crop vegetatively propagated by daughter‐plants produced by stolons, fruit yield is further dependent on the trade‐off between sexual reproduction (fruits) and asexual reproduction (daughter‐plants). Both are largely dependent on meristem identity, which establishes the development of branches, stolons and inflorescences.Floral initiation and plant architecture are modulated by the balance between two related proteins, FLOWERING LOCUS T (FT) and TERMINAL FLOWER 1 (TFL1). We explored in woodland strawberry the role of the uncharacterised FveFT2 and FveFT3 genes and of the floral repressor FveTFL1 through gene expression analyses, grafting and genetic transformation (overexpression and gene editing).We demonstrate the unusual properties of these genes. FveFT2 is a nonphotoperiodic florigen permitting short‐day (SD) flowering and FveTFL1 is the long‐hypothesised long‐day systemic antiflorigen that contributes, together with FveFT2, to the photoperiodic regulation of flowering. We additionally show that FveFT3 is not a florigen but promotes plant branching when overexpressed, that is likely to be through changing axillary meristem fate, therefore resulting in a 3.5‐fold increase in fruit yield at the expense of stolons.We show that our findings can be translated into improvement of cultivated strawberry in which FveFT2 overexpression significantly accelerates flowering.

Coleus (Plectranthus scutellarioides) is an attractive and popular ornamental plant with propagation mainly achieved through vegetative cuttings. For commercial purposes, it is of interest to enhance the speed of establishment while maintaining high quality. Light quality has been shown to influence adventitious root development, so these experiments examined the effect of narrow-bandwidth light treatments on root growth and overall plant quality for seven coleus cultivars with vegetative cuttings in potting soil and one cultivar with shoot tip in vitro cultures onto Murashige and Skoog (MS) agar medium. During the 28 days of the propagation period, the cuttings grown under narrow-bandwidth red light (R; 663.4 nm at peak) more than doubled in the adventitious root number compared with those under blue light (B; 445.7 nm at peak) and green light (G; 530.0 nm at peak) in five cultivars. R light also increased fresh weight of the cuttings by 55.6% more than G light. In comparison, the cuttings grown under G light yielded significantly lower root and shoot dry mass than other light treatments. R light cuttings showed more dry mass content (9.63%) than those under white light (W; 437.4 nm and 559.5 nm at peak) and G light (7.85% and 5.86%, respectively). A positive correlation (R2 = 0.598, P < 0.001) was found between the formation of adventitious roots and gained fresh weight of cuttings. R light made the reddish color of leaves significantly stronger in most cultivars, whereas the cuttings exposed to G light became less vivid compared with other light conditions. When the shoot tips were propagated in vitro onto MS medium, R light treatment initiated the root development more rapidly than other lights, with significantly greater rooting rate (20.0% and 63.6%, respectively) at day 5 and 10. The shoot tips under R light also formed significantly more roots (12.3 per cutting) than those grown under narrow-bandwidth B light (5.8 per cutting). The shoot tips showed browning at an early stage and newly emerged leaves grew very compactly under B light. The combination of red and green light (R+G) increased more than twice as much roots and dry mass compared with W light. In addition, the R+G light led to morphological changes, including larger leaves and longer petioles and internodes than those in other light treatments. The exposure to R+G+B and B light made the shoots very compact for the 28 days of in vitro culture period and significantly increased the chlorophyll contents resulting in dark green leaves.

Objective The treatment of plant tissue with Agrobacterium tumefaciens is often a critical first step to both stable and transient plant transformation. In both applications bacterial suspensions are oftentimes physically introduced into plant tissues using hand-driven pressure from a needleless syringe. While effective, this approach has several drawbacks that limit reproducibility. Pressure must be provided with the syringe perfectly perpendicular to the tissue surface. The researcher must also attempt to provide even and consistent pressure, both within and between experimental replicates. These factors mean that the procedures do not always translate well between research groups or biological replicates. Results We have devised a method to introduce Agrobacterium suspensions into plant leaves with greater reproducibility. Using a decommissioned dissecting microscope as an armature, a syringe body with the bacterial suspension is mounted to the nosepiece. Gentle, even pressure is applied by rotating the focus knob. The treatment force is measured using a basic kitchen scale. The development of the Standardized Pressure Agrobacterium Infiltration Device (SPAID) provides a means to deliver consistent amounts of bacterial suspensions into plant tissues with the goal of increasing reproducibility between replicates and laboratories.

Background Rosaceae include numerous economically important and morphologically diverse species. Comparative mapping between the member species in Rosaceae have indicated some level of synteny. Recently the whole genome of three crop species, peach, apple and strawberry, which belong to different genera of the Rosaceae family, have been sequenced, allowing in-depth comparison of these genomes. Results Our analysis using the whole genome sequences of peach, apple and strawberry identified 1399 orthologous regions between the three genomes, with a mean length of around 100 kb. Each peach chromosome showed major orthology mostly to one strawberry chromosome, but to more than two apple chromosomes, suggesting that the apple genome went through more chromosomal fissions in addition to the whole genome duplication after the divergence of the three genera. However, the distribution of contiguous ancestral regions, identified using the multiple genome rearrangements and ancestors (MGRA) algorithm, suggested that the Fragaria genome went through a greater number of small scale rearrangements compared to the other genomes since they diverged from a common ancestor. Using the contiguous ancestral regions, we reconstructed a hypothetical ancestral genome for the Rosaceae 7 composed of nine chromosomes and propose the evolutionary steps from the ancestral genome to the extant Fragaria, Prunus and Malus genomes. Conclusion Our analysis shows that different modes of evolution may have played major roles in different subfamilies of Rosaceae. The hypothetical ancestral genome of Rosaceae and the evolutionary steps that lead to three different lineages of Rosaceae will facilitate our understanding of plant genome evolution as well as have a practical impact on knowledge transfer among member species of Rosaceae., This project has been supported by the USDA NIFA SCRI grant # 2010-2010-03255. We acknowledge International Peach Genome Initiative for the permission to use the peach genome in this study

Powdery mildew (PM) caused by Podosphaera aphanis is a major fungal disease of cultivated strawberry. Mildew Resistance Locus O (MLO) is a gene family described for having conserved seven-transmembrane domains. Induced loss-of-function in specific MLO genes can confer durable and broad resistance against PM pathogens. However, the genomic structure and potential role of MLO genes for PM resistance have not been characterized yet in the octoploid cultivated strawberry. In the present study, MLO gene families were characterized in four diploid progenitor species (Fragaria vesca, F. iinumae, F. viridis, and F. nipponica) and octoploid cultivated (Fragaria ×ananassa) strawberry, and potential sources of MLO-mediated susceptibility were identified. Twenty MLO sequences were identified in F. vesca and 68 identified in F. ×ananassa. Phylogenetic analysis divided diploid and octoploid strawberry MLO genes into eight different clades, in which three FveMLO (MLO10, MLO17, and MLO20) and their twelve orthologs of FaMLO were grouped together with functionally characterized MLO genes conferring PM susceptibility. Copy number variations revealed differences in MLO composition among homoeologous chromosomes, supporting the distinct origin of each subgenome during the evolution of octoploid strawberry. Dissecting genomic sequence and structural variations in candidate FaMLO genes revealed their potential role associated with genetic controls and functionality in strawberry against PM pathogen. Furthermore, the gene expression profiling and RNAi silencing of putative FaMLO genes in response to the pathogen indicate the function in PM resistance. These results are a critical first step in understanding the function of strawberry MLO genes and will facilitate further genetic studies of PM resistance in cultivated strawberry.

We have developed and applied a novel strategy that can best be described as in vivo chemical genomics, a concept where populations of any transformable organism may be screened for consequences of novel RNAs or peptides. We created a library of ~800,000 random DNA sequences biased only by third-position nucleotide substitutions that suppress the frequency of termination codons. The sequences may be shuttled to any plant, microbial, or animal expression vector with recombination cloning. We then generated large populations of Arabidopsis thaliana plants, each expressing a randomized DNA sequence, presumably giving rise to synthetic RNA species and/or the peptides they encode. These novel molecules are produced within the context of the cell and have been shown to affect plant biology with a relatively high frequency, as evidenced by diverse phenotypes. This chapter provides the protocols necessary to construct the libraries and isolate plants expressing randomized DNA sequences.

We have developed and applied a novel strategy that can best be described as in vivo chemical genomics, a concept where populations of any transformable organism may be screened for consequences of novel RNAs or peptides. We created a library of ~800,000 random DNA sequences biased only by third-position nucleotide substitutions that suppress the frequency of termination codons. The sequences may be shuttled to any plant, microbial, or animal expression vector with recombination cloning. We then generated large populations of Arabidopsis thaliana plants, each expressing a randomized DNA sequence, presumably giving rise to synthetic RNA species and/or the peptides they encode. These novel molecules are produced within the context of the cell and have been shown to affect plant biology with a relatively high frequency, as evidenced by diverse phenotypes. This chapter provides the protocols necessary to construct the libraries and isolate plants expressing randomized DNA sequences.

The cultivated strawberry (Fragaria × ananassa) is an economically important fruit crop that is intensively bred for improved sensory qualities. The diversity of fruit flavors and aromas in strawberry results mainly from the interactions of sugars, acids, and volatile organic compounds (VOCs) that are derived from diverse biochemical pathways influenced by the expression of many genes. This study integrates multiomic analyses to identify QTL and candidate genes for multiple aroma compounds in a complex strawberry breeding population. Novel fruit volatile QTL was discovered for methyl anthranilate, methyl 2-hexenoate, methyl 2-methylbutyrate, mesifurane, and a shared QTL on Chr 3 was found for nine monoterpene and sesquiterpene compounds, including linalool, 3-carene, β-phellandrene, α-limonene, linalool oxide, nerolidol, α-caryophellene, α-farnesene, and β-farnesene. Fruit transcriptomes from a subset of 64 individuals were used to support candidate gene identification. For methyl esters including the grape-like methyl anthranilate, a novel ANTHANILIC ACID METHYL TRANSFERASE–like gene was identified. Two mesifurane QTL correspond with the known biosynthesis gene O-METHYL TRANSFERASE 1 and a novel FURANEOL GLUCOSYLTRANSFERASE. The shared terpene QTL contains multiple fruit-expressed terpenoid pathway-related genes including NEROLIDOL SYNTHASE 1 (FanNES1). The abundance of linalool and other monoterpenes is partially governed by a co-segregating expression-QTL (eQTL) for FanNES1 transcript variation, and there is additional evidence for quantitative effects from other terpenoid-pathway genes in this narrow genomic region. These QTLs present new opportunities in breeding for improved flavor in commercial strawberry.

The cultivated strawberry (Fragaria ×ananassa) is an economically important fruit crop that is intensively bred for improved sensory qualities. The diversity of fruit flavors and aromas in strawberry result mainly from the interactions of sugars, acids, and volatile organic compounds (VOCs) that are derived from diverse biochemical pathways influenced by the expression of many genes. This study integrates multi-omics analyses to identify QTL and candidate genes for multiple aroma compounds in a complex strawberry breeding population. Novel fruit volatile QTL were discovered for methyl anthranilate, methyl 2-hexenoate, methyl 2-methylbutyrate, mesifurane, and a shared QTL on Chr 3 was found for nine monoterpene and sesquiterpene compounds, including linalool, 3-carene, β-phellandrene, α-limonene, linalool oxide, nerolidol, α-caryophellene, α-farnesene, and β-farnesene. Fruit transcriptomes from a subset of sixty-four individuals were used to support candidate gene identification. For methyl esters including the grape-like methyl anthranilate, a novel ANTHANILIC ACID METHYL TRANSFERASE–like gene was identified. Two mesifurane QTL correspond with the known biosynthesis gene O-METHYL TRANSFERASE 1 and a novel FURANEOL GLUCOSYLTRANSFERASE. The shared terpene QTL contains multiple fruit-expressed terpenoid pathway-related genes including NEROLIDOL SYNTHASE 1 (FanNES1). The abundance of linalool and other monoterpenes is partially governed by a co-segregating expression-QTL (eQTL) for FanNES1 transcript variation, and there is additional evidence for quantitative effects from other terpenoid-pathway genes in this narrow genomic region. These QTL present new opportunities in breeding for improved flavor in commercial strawberry.

The commercial strawberry, Fragaria × ananassa, is a recent allo-octoploid that is cultivated worldwide. However, other than Fragaria vesca, which is universally accepted one of its diploid ancestors, its other early diploid progenitors remain unclear. Here, we performed comparative analyses of the genomes of five diploid strawberries, F. iinumae, F. vesca, F. nilgerrensis, F. nubicola, and F. viridis, of which the latter three are newly sequenced. We found that the genomes of these species share highly conserved gene content and gene order. Using an alignment-based approach, we show that F. iinumae and F. vesca are the diploid progenitors to the octoploid F. × ananassa, whereas the other three diploids that we analyzed in this study are not parental species. We generated a fully resolved, dated phylogeny of Fragaria, and determined that the genus arose ∼6.37 Ma. Our results effectively resolve conflicting hypotheses regarding the putative diploid progenitors of the cultivated strawberry, establish a reliable backbone phylogeny for the genus, and provide genetic resources for molecular breeding.

Powdery mildew (PM) caused by Podosphaera aphanis is a major fungal disease in cultivated strawberry. Mildew Resistance Locus O (MLO) is a gene family described for having conserved seven-transmembrane domains. Induced loss-of-function in specific MLO genes can confer durable and broad resistance against PM pathogens. However, the underlying biological role of MLO genes in strawberry is still unknown. In the present study, the genomic structure of MLO genes were characterized in both diploid (Fragaria vesca) and octoploid strawberry (Fragaria ×ananassa), and the potential sources of MLO-mediated susceptibility were identified. Twenty MLO-like sequences were identified in F. vesca, with sixty-eight in F. ×ananassa. Phylogenetic analysis divides strawberry MLO genes into eight different clades, in which three FveMLO and ten FaMLO genes were grouped together with the functionally known MLO susceptibility. Out of ten FaMLO genes, FaMLO17-2 and FaMLO17-3 showed the highest similarity to the known susceptibility MLO proteins. Gene expression analysis of FaMLO genes was conducted using a multi-parental segregating population. Three expression quantitative trait loci (eQTL) were substantially associated with MLO transcript levels in mature fruits, suggesting discrete genetic control of susceptibility. These results are a critical first step in understanding allele function of MLO genes, and are necessary for further genetic studies of PM resistance in cultivated strawberry.

Octoploid strawberry (Fragaria ×ananassa) is a major specialty crop under intense annual selection for traits relating to plant vigor and fruit quality. Most functional validation experiments rely on transgenic or transient gene expression assays in the mature receptacle. These findings are not typically translatable to breeding without identifying a natural genetic source of transcript level variation, and developing reliable markers for selection in octoploids. Expression QTL (eQTL) analysis is a genetic/transcriptomic association approach for identifying sequence variants predicting differential expression. This eQTL study analyzed a wide array of mature receptacle-expressed genes, encompassing the majority of total mature receptacle transcript accumulation and almost all strawberry genes described in the literature. These results identified segregating genetic variants associated with the differential expression of hundreds of strawberry genes, many with known interest to breeders. Several of these eQTL pertain to published genes whose expression levels have been demonstrated to influence mature receptacle phenotypes. Many include key genes of the phenylpropanoid pathway, vitamin C, carotenoid, pectin, and receptacle carbohydrate/sugar metabolism. These subgenome-specific genetic markers may allow breeders to select for desired ranges of target gene expression. These results may also guide basic research efforts and facilitate the identification of causal genes underlying trait QTL.

Rapid Alkalinization Factors (RALFs) are cysteine-rich peptides ubiquitous within plant kingdom. They play multiple roles as hormonal signals in diverse processes, including root elongation, cell growth, pollen tube development, and fertilization. Their involvement in host-pathogen crosstalk as negative regulators of immunity in Arabidopsis has also been recognized. In addition, peptides homologous to RALF are secreted by different fungal pathogens as effectors during early stages of infection. Previous studies have identified nine RALF genes in the diploid strawberry (Fragaria vesca) genome. This work describes the genomic organization of the RALF gene families in commercial octoploid strawberry (Fragaria × ananassa) and the re-annotated genome of F. vesca, and then compares findings with orthologs in Arabidopsis thaliana. We reveal the presence of 15 RALF genes in F. vesca genotype Hawaii 4 and 50 in Fragaria x ananassa cv. Camarosa, showing a non-homogenous localization of genes among the different Fragaria x ananassa subgenomes. Expression analysis of Fragaria x ananassa RALF genes upon infection with Colletotrichum acutatum or Botrytis cinerea showed that FanRALF3-1 was the only fruit RALF gene upregulated after fungal infection. In silico analysis was used to identify distinct pathogen inducible elements upstream of the FanRALF3-1 gene. Agroinfiltration of strawberry fruit with deletion constructs of the FanRALF3-1 promoter identified a 5' region required for FanRALF3-1 expression in fruit, but failed to identify a region responsible for fungal induced expression.

Rapid Alkalinization Factor (RALF) are cysteins-rich peptides ubiquitous in plant kingdom. They play multiple roles as hormone signals, starting from root elongation, cell growth, pollen tube development and fertilization. Their involvement in host-pathogen crosstalk as negative regulator of immunity in Arabidopsis has also been recognized. In addition, RALF peptides are secreted by different fungal pathogens as effectors during early stages of infections. Campbell and Turner previously identified nine RALF genes in F. vesca v1 genome. Here, based on the recent release of Fragaria x ananassa genome and F. vesca reannotation, we aimed to characterize the genomic organization of the RALF gene family in both type of strawberry species according to tissue specific expression and homology with Arabidopsis. We reveal the presence of 13 RALF genes in F. vesca and 50 in Fragaria x ananassa, showing a non-homogenous localization of genes among the different Fragaria x ananassa subgenomes associated with their different TE element contents and genome remodeling during evolution. Fragaria x ananassa RALF genes expression inducibility upon infection with C. acutatum or B. cinerea was assessed and showed that, among fruit expressed RALF genes, FaRALF3-1 was the only one upregulated after fungal infection. In silico analysis and motif frequency analysis of the putative regulatory elements upstream of the FaRALF3 gene was carried out in order to identify distinct pathogen inducible elements. Agroinfiltration of strawberry fruit with 5’ deletion constructs of the FaRALF3-1 promoter identified a region required for FaRALF3 expression in fruit, but did not identify a region responsible for fungal induced expression.

To address science literacy issues, university faculty have to engage in effective science communication. However, social pressures from peers, administration, or the public may silence their efforts. The purpose of this study was to understand the effect of the spiral of silence on faculty's engagement with science communication. A survey was distributed to a census of tenure-track faculty at the University of Florida [UF], and the findings did not support the spiral of silence was occurring. However, follow-up interviews revealed faculty did not perceive their peers to value science communication and were more concerned about how the public felt about their research and communication.

There is substantial interest in growing crops in closed controlled environments, yet the energy requirements are high. Energy is required to produce light, but also to remove the heat generated when producing light. The goal of the current work examines a possible approach to decrease the energy requirement. The effect of pulsed light treatments was examined by monitoring seedling traits during early photomorphogenic development. Daily light integral remained unchanged between treatments, but the frequency of the pulses was varied. Developmental traits (such as inhibition of hypocotyl elongation rate) were most conspicuous during a normal photoperiod, as in twelve hours light, twelve hours darkness. Consistent with historical reports, when treatments were delivered in shorter durations (e.g. 1 hour on/off) photomorphogenic development was hindered, with the same daily light integral. However, at even shorter light intervals (e.g. seconds) seedlings developed as if they were provided full 12 h treatments. Extension of the dark period following a 5 s pulse was tested to determine the effect on seedling traits. The results showed that the dark period could be extended to at least 10 s without affecting seedling development, and extension to 20 s only had slight effects on seedling traits. The mechanism of the phenomenon was examined in Arabidopsis photosensory mutants, with substantial contributions from the phyA and cry1 pathways. The results suggest that pulsed light with extended dark periods can decrease energy input by at least 30% to >50% without affecting visible seedling traits. These pilot experiments in seedlings demonstrate that implementation of short-interval, pulsed-light strategies may lower energy requirements for growing crops in artificially illuminated environments.

We have identified a synthetic peptide that interrupts discrete aspects of seedling development under red light. Previous reports have demonstrated that plants transformed with random DNA sequences produce synthetic peptides that affect plant biology. In this report one specific peptide is characterized that inhibits discrete aspects of red-light-mediated Arabidopsis thaliana development during photomorphogenesis. Seedlings expressing the PEP6-32 peptide presented longer hypocotyls and diminished cotyledon expansion when grown under red light. Other red-light-mediated seedling processes such as induction of Lhcb (cab) transcripts or loss of vertical growth remained unaffected. Long-term responses to red light in PEP6-32 expressing plants, such as repression of flowering time, did not show defects in red light signaling or integration. A synthesized peptide applied exogenously induced the long-hypocotyl phenotype under red light in non-transformed seedlings. The results indicate that the PEP6-32 peptide causes discrete cell expansion defects during early seedling development in red light, mimicking weak phyB alleles in some aspects of seedling photomorphogenesis. The findings demonstrate that new chemistries derived from random peptide expression can modulate specific facets of plant growth and development.One Sentence SummaryA plant line expressing random DNA sequence expresses a synthetic peptide that affects specific red-light responses in a developing seedling.

Octoploid strawberry (Fragaria × ananassa) is a valuable specialty crop, but profitable production and availability are threatened by many pathogens. Efforts to identify and introgress useful disease resistance genes (R-genes) in breeding programs are complicated by strawberry’s complex octoploid genome. Recently-developed resources in strawberry, including a complete octoploid reference genome and high-resolution octoploid genotyping, enable new analyses in strawberry disease resistance genetics. This study characterizes the complete R-gene collection in the genomes of commercial octoploid strawberry and two diploid ancestral relatives, and introduces several new technological and data resources for strawberry disease resistance research. These include octoploid R-gene transcription profiling, dN/dS analysis, eQTL analysis and RenSeq analysis in cultivars. Octoploid fruit transcript expression quantitative trait loci (eQTL) were identified for 77 putative R-genes. R-genes from the ancestral diploids Fragaria vesca and Fragaria iinumae were compared, revealing differential inheritance and retention of various octoploid R-gene subtypes. The mode and magnitude of natural selection of individual F. × ananassa R-genes was also determined via dN/dS analysis. R-gene sequencing using enriched libraries (RenSeq) has been used recently for R-gene discovery in many crops, however this technique somewhat relies upon a priori knowledge of desired sequences. An octoploid strawberry capture-probe panel, derived from the results of this study, is validated in a RenSeq experiment and is presented for community use. These results give unprecedented insight into crop disease resistance genetics, and represent an advance towards exploiting variation for strawberry cultivar improvement.

Conventional breeding of the cultivated strawberry (Fragaria × ananassa) is hindered by a complicated octoploid genome and a paucity of molecular markers. Genetic improvement may be accelerated by direct gene-transfer techniques that could address single-gene deficiencies in otherwise commercially valuable selections. ‘Cisgenic’ or “intragenic” approaches face fewer regulatory hurdles, yet more characterized promoters and selectable markers are needed for the development of such technologies in strawberry. This report tests a number of putative promoters and a potential selectable marker for use in cisgenic vector development. Based on RNAseq data, the 5′-proximal noncoding regions from highly expressed transcripts were tested for activity. These putative promoter sequences were fused to eGFP and GUS reporter genes and transiently expressed in both Nicotiana benthamiana leaves and F. × ananassa strawberry fruits. The promoter sequences of FanAPA1-related and FanUBCE2 present constitutive promoter candidates that are active in all tissues tested. A potential selectable marker from strawberry sequence, the coding region of the strawberry 5-enolpyruvylshikimate 3 phosphatase synthase (EPSPS) gene, was cloned and mutagenized, and then stably transformed into Arabidopsis plants. Overexpression of the non-mutagenized form confers resistance to glyphosate, showing potential utility as a selectable marker. The results of these trials define new tools for the development of intragenic vectors in strawberry.