An official website of the United States government
Summary Day neutrality, or insensitivity to photoperiod (day length), is an important domestication trait in many crop species. Although the oilseed cropCamelina sativahas been cultivated since the Neolithic era, day-neutral accessions have yet to be described. We sought to leverage genetic diversity in existing germplasms to identifyC. sativaaccessions with low photoperiod sensitivity for future engineering of this trait. We quantified variation in the photoperiod response across 161 accessions ofC. sativaby measuring hypocotyl length of four-day-old seedlings grown in long-day and short-day conditions, finding wide variation in photoperiod response. Similarly, soil-grown adult plants from selected accessions showed variation in photoperiod response in several traits; however, photoperiod responses in seedling and adult traits were not correlated, suggesting complex mechanistic underpinnings. Although RNA-seq experiments of the reference accession Licalla identified several differentially regulatedArabidopsissyntelogs involved in photoperiod response, includingCOL2, FT, LHYandWOX4, expression of these genes in the accessions did not correlate with differences in their photoperiod sensitivity. Taken together, we show that all tested accessions show some degree of photoperiod response, and that this trait is likely complex, involving several and separable seedling and adult traits. Significance StatementDay neutrality (photoperiod insensitivity) is a common trait in domesticated crops; however, the ancient oilseed cropCamelina sativahas remained photoperiod-sensitive, which likely limits seed yields. Here, we show that photoperiod sensitivity is conserved across manyC. sativacultivars, albeit to different degrees, and we establish that photoperiod sensitivity is a complex trait, which will require genetic engineering to achieve day neutrality.
more »
« less
Sensitivity to Photoperiod Is a Complex Trait in Camelina sativa
ABSTRACT Day neutrality, or insensitivity to photoperiod (day length), is an important domestication trait in many crop species. Although the oilseed cropC. sativahas been cultivated since the Neolithic era, day‐neutral accessions have yet to be described. We sought to leverage genetic diversity in existing germplasms to identifyC. sativaaccessions with low photoperiod sensitivity for future engineering of this trait. To do so, we quantified variation in hypocotyl length across 161C. sativaaccessions of 4‐day‐old seedlings grown in long‐day and short‐day conditions as a high‐throughput approximation of variation in the photoperiod response. Soil‐grown adult plants from selected accessions also showed variation in the response to day length in several traits; however, the responses in seedling and adult traits were not correlated, suggesting complex mechanistic underpinnings. Although RNA‐seq experiments of the reference accession Licalla identified several differentially regulatedArabidopsissyntelogs involved in photoperiod response and development, includingCOL2,FT,LHY, andWOX4,expression of these genes in the accessions did not correlate with differences in their photoperiod sensitivity. Taken together, we show that all tested accessions show some degree of photoperiod response and that this trait is likely complex, involving several and separable seedling and adult traits.
more »
« less
- Award ID(s):
- 2240888
- PAR ID:
- 10664360
- Publisher / Repository:
- Plant Direct published by American Society of Plant Biologists and the Society for Experimental Biology and John Wiley & Sons Ltd
- Date Published:
- Journal Name:
- Plant Direct
- Volume:
- 9
- Issue:
- 4
- ISSN:
- 2475-4455
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
More Like this
-
-
Plant functional traits are vital tools in ecological restoration and biodiversity conservation. While functional traits and functional diversity are increasingly being used to inform restoration efforts, challenges remain in the characterization of trait variation in many systems, including within‐species. Likewise, understanding axes of trait variation describing trade‐offs in plant function is important for trait‐based restoration frameworks, yet the degree of coordination between above‐ground functional traits and their below‐ ground counterparts is often unknown. Here, we investigate intraspecific trait variation among five populations ofSchizachyrium scoparium(little bluestem), a species commonly used for restoration, from different habitat types across a gradient from southern Wisconsin to Northern Illinois. We asked (1) how regional populations ofS. scopariumdiffer in their functional traits, (2) how functional trait variation inS. scopariumis structured among and within populations, and (3) how above‐ and below‐ground functional traits ofS. scopariumcoordinate and describe axes of functional trade‐offs. We found that populations differed in multivariate trait space, but evidence for differences in individual traits among populations was mixed. Trait relationships with habitat types were idiosyncratic and often misaligned with expectations of plant economic spectra. Variation within populations was as high, or higher, than between populations across traits. We found evidence for weak coordination in several trait pairs, including two above‐ and below‐ground trait combinations, while others appeared to be uncoordinated. Our findings support previous research that trait differentiation can occur at multiple scales, both between and within populations. Extensive within‐population trait variability could be leveraged in trait‐based restoration frameworks targeting intraspecific functional diversity. The lack of strong signals of coordination between above‐ and below‐ground functional traits suggest that sourcing decisions meant to match below‐ground functional traits to recipient restored communities should rely on direct measurement of root traits associated with desired functions rather than above‐ground proxies.more » « less
-
ABSTRACT Miscanthusholds a promise as a biocrop due to its high yield, perenniality and ability to grow on infertile soils. However, the current commercial biomass production ofMiscanthusis mostly limited to a single sterile triploid clone ofM.×giganteus. Nevertheless, parental species ofM.×giganteus, MiscanthussacchariflorusandMiscanthussinensiscontain vast genetic diversity for crop improvement. WithM. sacchariflorushaving a natural geographic distribution in cold‐temperate northeast China and eastern Russia, we hypothesised that it has substantial variation in physiological response to chilling. Using a semi‐high‐throughput method, we phenotyped 209M. sacchariflorusgenotypes belonging to six genetic groups for non‐photochemical quenching (NPQ) and photosystem II efficiency (ΦPSII) kinetics under warm and chilling treatments in three growing seasons. In response to the chilling treatment, all genetic groups exhibited an increase in NPQ induction rate indicating faster activation of NPQ in light. Notably, under chilling, the Korea/NE China/Russia 2x and N China 2x groups stood out for the highest NPQ rate in light and the highest steady‐state NPQ in light. This NPQ phenotype may contribute adaptation to chilling during bright, cold mornings of spring and early autumn in temperate climates, when faster NPQ would better protect from oxidative stress. Such enhanced adaptation could expand the growing season and thus productivity at a given location or expand the range of economically viable growing locations to higher latitudes and altitudes. A genome‐wide association study identified 126 unique SNPs associated with NPQ and ΦPSII traits. Among the identified candidate genes were enzymes involved in the ascorbate recycle and shikimate pathway, gamma‐aminobutyric acid and cation efflux transporters. Identifying natural variation and genes involved in NPQ and ΦPSII kinetics considerably enlarges the toolbox for breeding and/or engineeringMiscanthuswith optimised photosynthesis under warm and chilling conditions for sustainable feedstock production for bioenergy. Chilling affects the productivity and geographical distribution of most crops. Using a semi‐high‐throughput approach to investigate photosynthesis‐related traits, we characterised variation existing in the bioenergy cropMiscanthusunder chilling and warm conditions and identified potential genes associated with it. Under chilling, two genetic groups from the northern edge ofMiscanthusdistribution stood out for faster activation of photoprotection. This trait may contribute adaptation to chilling in temperate climates, when faster photoprotection would better defend from oxidative stress. Enhanced chilling adaptation could expand the growing season and thus productivity or enlarge the range of growing locations.more » « less
-
Societal Impact StatementGroundcherry (Physalis grisea) is a plant species grown for its flavorful fruit. The fruit drops from the plant, hence the common name groundcherry. This makes harvest cumbersome and puts the fruit at risk for carrying soil‐borne pathogens, therefore making them unsellable. Furthermore, insects often damage the plants, reducing yield. Advances in gene editing offer promise for addressing these issues and aiding home gardeners and farmers. Improvement will expand access to this nutritious fruit, rich in potassium, vitamin C, and antioxidants. Additionally, studies of its biology could serve as a model for improving other fruiting plants, particularly underutilized species. SummaryP. griseais an underutilized, semidomesticated fruit crop with rising agronomic value. Several resources have been developed for its use in fundamental biological research, including a plant transformation system and a high‐quality reference genome. Already,P. griseahas been used as a model to investigate biological phenomena including inflated calyx syndrome and gene compensation.P. griseahas also been used to demonstrate the potential of fast‐tracking domestication trait improvement through approaches such as CRISPR/Cas9 gene editing. This work has led to thePhysalisImprovement Project, which relies on reverse genetics to understand the mechanisms that underlie fruit abscission and plant–herbivore interactions to guide approaches for improvement of undesirable characteristics. CRISPR/Cas9 gene editing has been used to targetP. griseagenes that are suspected to act in fruit abscission, particularly orthologs of those that are reported in tomato abscission zone development. A similar approach is being taken to targetP. griseagenes involved in the withanolide biosynthetic pathway to determine the impact of withanolides on plant–herbivore interactions. Results from these research projects will lead to a greater understanding of important biological processes and will also generate knowledge needed to develop cultivars with reduced fruit drop and increased resistance to insect herbivory.more » « less
-
ABSTRACT Herbicide resistance in agricultural weeds has become one of the greatest challenges for sustainable crop production. The repeated evolution of herbicide resistance provides an excellent opportunity to study the genetic and physiological basis of the resistance phenotype and the evolutionary responses to human‐mediated selection pressures.Lolium multiflorumis a ubiquitous weed that has evolved herbicide resistance repeatedly around the world in various cropping systems. We assembled and annotated a chromosome‐scale genome forL. multiflorumand elucidated the genetic architecture of paraquat resistance by performing quantitative trait locus analysis, genome‐wide association studies, genetic divergence analysis and transcriptome analyses from paraquat‐resistant and ‐susceptibleL. multiflorumplants. We identified two regions on chromosome 5 that were associated with paraquat resistance. These regions both showed evidence for positive selection among the resistant populations we sampled, but the effects of this selection on the genome differed, implying a complex evolutionary history. In addition, these regions contained candidate genes that encoded cellular transport functions, including a novel multidrug and toxin extrusion (MATE) protein and a cation transporter previously shown to interact with polyamines. Given thatL. multiflorumis a weed and a cultivated crop species, the genomic resources generated will prove valuable to a wide spectrum of the plant science community. Our work contributes to a growing body of knowledge on the underlying evolutionary and ecological dynamics of rapid adaptation to strong anthropogenic selection pressure that could help initiate efforts to improve weed management practices in the long term for a more sustainable agriculture.more » « less
- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1002/pld3.70071
