المؤلفون: Jonathon A. Gibbs, Lorna Mcausland, Carlos A. Robles-Zazueta, Erik H. Murchie, Alexandra J. Burgess

المصدر: Frontiers in Plant Science, Vol 12 (2021)

مصطلحات موضوعية: deep learning, gsmax – maximum stomatal conductance, high-throughput phenotyping, semantic segmentation, stomata, Plant culture, SB1-1110

الوصف: Stomata are integral to plant performance, enabling the exchange of gases between the atmosphere and the plant. The anatomy of stomata influences conductance properties with the maximal conductance rate, gsmax, calculated from density and size. However, current calculations of stomatal dimensions are performed manually, which are time-consuming and error prone. Here, we show how automated morphometry from leaf impressions can predict a functional property: the anatomical gsmax. A deep learning network was derived to preserve stomatal morphometry via semantic segmentation. This forms part of an automated pipeline to measure stomata traits for the estimation of anatomical gsmax. The proposed pipeline achieves accuracy of 100% for the distinction (wheat vs. poplar) and detection of stomata in both datasets. The automated deep learning-based method gave estimates for gsmax within 3.8 and 1.9% of those values manually calculated from an expert for a wheat and poplar dataset, respectively. Semantic segmentation provides a rapid and repeatable method for the estimation of anatomical gsmax from microscopic images of leaf impressions. This advanced method provides a step toward reducing the bottleneck associated with plant phenotyping approaches and will provide a rapid method to assess gas fluxes in plants based on stomata morphometry.

وصف الملف: electronic resource

العلاقة: https://www.frontiersin.org/articles/10.3389/fpls.2021.780180/fullTest; https://doaj.org/toc/1664-462XTest

الوصول الحر: https://doaj.org/article/8561a7030a4143a7ac1c866c04c6c2ceTest

المؤلفون: Lorna McAusland, Jonathan A. Atkinson, Tracy Lawson, Erik H. Murchie

المصدر: Plant Methods, Vol 15, Iss 1, Pp 1-15 (2019)

مصطلحات موضوعية: Photosynthesis, Photo-protection, Chlorophyll fluorescence, Dynamic, Phenotyping, Imaging, Plant culture, SB1-1110, Biology (General), QH301-705.5

الوصف: Abstract Background As yields of major crops such as wheat (T. aestivum) have begun to plateau in recent years, there is growing pressure to efficiently phenotype large populations for traits associated with genetic advancement in yield. Photosynthesis encompasses a range of steady state and dynamic traits that are key targets for raising Radiation Use Efficiency (RUE), biomass production and grain yield in crops. Traditional methodologies to assess the full range of responses of photosynthesis, such a leaf gas exchange, are slow and limited to one leaf (or part of a leaf) per instrument. Due to constraints imposed by time, equipment and plant size, photosynthetic data is often collected at one or two phenological stages and in response to limited environmental conditions. Results Here we describe a high throughput procedure utilising chlorophyll fluorescence imaging to phenotype dynamic photosynthesis and photoprotection in excised leaves under controlled gaseous conditions. When measured throughout the day, no significant differences (P > 0.081) were observed between the responses of excised and intact leaves. Using excised leaves, the response of three cultivars of T. aestivum to a user—defined dynamic lighting regime was examined. Cultivar specific differences were observed for maximum PSII efficiency (F v′/F m′—P 130 μmol m−2 s−1 photosynthetic photon flux density (PPFD). Conclusions Here we demonstrate the development of a high-throughput (> 500 samples day−1) method for phenotyping photosynthetic and photo-protective parameters in a dynamic light environment. The technique exploits chlorophyll fluorescence imaging in a specifically designed chamber, enabling controlled gaseous environment around leaf sections. In addition, we have demonstrated that leaf sections do not different from intact plant material even > 3 h after sampling, thus enabling transportation of material of interest from the field to this laboratory based platform. The methodologies described here allow rapid, custom screening of field material for variation in photosynthetic processes.

وصف الملف: electronic resource

العلاقة: http://link.springer.com/article/10.1186/s13007-019-0485-xTest; https://doaj.org/toc/1746-4811Test

الوصول الحر: https://doaj.org/article/3c40491ea2ad4977ba0e4a6293f8b928Test

المؤلفون: Lorna McAusland, Mui-Ting Lim, David E. Morris, Hayley L. Smith-Herman, Umar Mohammed, Barrie R. Hayes-Gill, John A. Crowe, Ian D. Fisk, Erik H. Murchie

المصدر: Frontiers in Plant Science, Vol 11 (2020)

مصطلحات موضوعية: coriander, vertical farming, aroma, spectrum, light-emitting diodes, photosynthesis, Plant culture, SB1-1110

الوصف: Advancements in availability and specificity of light-emitting diodes (LEDs) have facilitated trait modification of high-value edible herbs and vegetables through the fine manipulation of spectra. Coriander (Coriandrum sativum L.) is a culinary herb, known for its fresh, citrusy aroma, and high economic value. Studies into the impact of light intensity and spectrum on C. sativum physiology, morphology, and aroma are limited. Using a nasal impact frequency panel, a selection of key compounds associated with the characteristic aroma of coriander was identified. Significant differences (P < 0.05) were observed in the concentration of these aromatics between plants grown in a controlled environment chamber under the same photosynthetic photon flux density (PPFD) but custom spectra: red (100%), blue (100%), red + blue (RB, 50% equal contribution), or red + green + blue (RGB, 35.8% red: 26.4% green: 37.8% blue) wavelengths. In general, the concentration of aromatics increased with increasing numbers of wavelengths emitted alongside selective changes, e.g., the greatest increase in coriander-defining E-(2)-decenal occurred under the RGB spectrum. This change in aroma profile was accompanied by significant differences (P < 0.05) in light saturated photosynthetic CO2 assimilation, water-use efficiency (Wi), and morphology. While plants grown under red wavelengths achieved the greatest leaf area, RB spectrum plants were shortest and had the highest leaf:shoot ratio. Therefore, this work evidences a trade-off between sellable commercial morphologies with a weaker, less desirable aroma or a less desirable morphology with more intense coriander-like aromas. When supplemental trichromatic LEDs were used in a commercial glasshouse, the majority of compounds, with the exception of linalool, also increased showing that even as a supplement additional wavelength can modify the aromatic profile increasing its complexity. Lower levels of linalool suggest these plants may be more susceptible to biotic stress such as herbivory. Finally, the concentration of coriander-defining aromatics E-(2)-decenal and E-(2)-hexenal was significantly higher in supermarket pre-packaged coriander leaves implying that concentrations of aromatics increase after excision. In summary, spectra can be used to co-manipulate aroma profile and plant form with increasing spectral complexity leading to greater aromatic complexity and intensity. We suggest that increasing spectral complexity progressively stimulates signaling pathways giving rise to valuable economic traits.

وصف الملف: electronic resource

العلاقة: https://www.frontiersin.org/article/10.3389/fpls.2020.00462/fullTest; https://doaj.org/toc/1664-462XTest

الوصول الحر: https://doaj.org/article/bab41e7832b64595b98c6c0db28be906Test

المؤلفون: Niaz Ahmad, Muhammad Omar Khan, Ejazul Islam, Zheng-Yi Wei, Lorna McAusland, Tracy Lawson, Giles N. Johnson, Peter J. Nixon

المصدر: Frontiers in Plant Science, Vol 11 (2020)

مصطلحات موضوعية: PTOX, chloroplasts, chlororespiration, photoinhibition, stress tolerance, Plant culture, SB1-1110

الوصف: The plastid terminal oxidase (PTOX) – an interfacial diiron carboxylate protein found in the thylakoid membranes of chloroplasts – oxidizes plastoquinol and reduces molecular oxygen to water. It is believed to play a physiologically important role in the response of some plant species to light and salt (NaCl) stress by diverting excess electrons to oxygen thereby protecting photosystem II (PSII) from photodamage. PTOX is therefore a candidate for engineering stress tolerance in crop plants. Previously, we used chloroplast transformation technology to over express PTOX1 from the green alga Chlamydomonas reinhardtii in tobacco (generating line Nt-PTOX-OE). Contrary to expectation, growth of Nt-PTOX-OE plants was more sensitive to light stress. Here we have examined in detail the effects of PTOX1 on photosynthesis in Nt-PTOX-OE tobacco plants grown at two different light intensities. Under ‘low light’ (50 μmol photons m–2 s–1) conditions, Nt-PTOX-OE and WT plants showed similar photosynthetic activities. In contrast, under ‘high light’ (125 μmol photons m–2 s–1) conditions, Nt-PTOX-OE showed less PSII activity than WT while photosystem I (PSI) activity was unaffected. Nt-PTOX-OE grown under high light also failed to increase the chlorophyll a/b ratio and the maximum rate of CO2 assimilation compared to low-light grown plants, suggesting a defect in acclimation. In contrast, Nt-PTOX-OE plants showed much better germination, root length, and shoot biomass accumulation than WT when exposed to high levels of NaCl and showed better recovery and less chlorophyll bleaching after NaCl stress when grown hydroponically. Overall, our results strengthen the link between PTOX and the resistance of plants to salt stress.

وصف الملف: electronic resource

العلاقة: https://www.frontiersin.org/article/10.3389/fpls.2020.00501/fullTest; https://doaj.org/toc/1664-462XTest

الوصول الحر: https://doaj.org/article/25ee8804e7c94ffeaae13acc80d00c59Test

المؤلفون: Alexandra M. Przewieslik-Allen, Amanda J. Burridge, Paul A. Wilkinson, Mark O. Winfield, Daniel S. Shaw, Lorna McAusland, Julie King, Ian P. King, Keith J. Edwards, Gary L. A. Barker

المصدر: Frontiers in Plant Science, Vol 9 (2019)

مصطلحات موضوعية: Aegilops, wheat, genotyping array, single nucleotide polymorphism (SNP), introgression, wheat relative, Plant culture, SB1-1110

الوصف: The genus Aegilops contains a diverse collection of wild species exhibiting variation in geographical distribution, ecological adaptation, ploidy and genome organization. Aegilops is the most closely related genus to Triticum which includes cultivated wheat, a globally important crop that has a limited gene pool for modern breeding. Aegilops species are a potential future resource for wheat breeding for traits, such as adaptation to different ecological conditions and pest and disease resistance. This study describes the development and application of the first high-throughput genotyping platform specifically designed for screening wheat relative species. The platform was used to screen multiple accessions representing all species in the genus Aegilops. Firstly, the data was demonstrated to be useful for screening diversity and examining relationships within and between Aegilops species. Secondly, markers able to characterize and track introgressions from Aegilops species in hexaploid wheat were identified and validated using two different approaches.

وصف الملف: electronic resource

العلاقة: https://www.frontiersin.org/article/10.3389/fpls.2018.01993/fullTest; https://doaj.org/toc/1664-462XTest

الوصول الحر: https://doaj.org/article/9b19ba1832d8424f82e73776fd18630dTest

المؤلفون: Erik Murchie, Matthew Paul Reynolds, Gustavo Slafer, John Foulkes, Liana Acevedo-Siaca, Lorna Mcausland, Simon Griffiths, A Elizabete Carmo-Silva

مصطلحات موضوعية: Source-Sink, Yield Physiology, info:eu-repo/classification/cti/6, info:eu-repo/classification/agrovoc/BIOMASS, info:eu-repo/classification/agrovoc/BREEDING, info:eu-repo/classification/agrovoc/PHOTOSYNTHESIS, info:eu-repo/classification/agrovoc/SOURCE SINK RELATIONS, info:eu-repo/classification/agrovoc/YIELDS, info:eu-repo/classification/agrovoc/PHYSIOLOGY

وصف الملف: application/pdf

العلاقة: https://hdl.handle.net/10883/22698Test

الإتاحة: https://hdl.handle.net/10883/22698Test

المؤلفون: Lorna Mcausland, Liana Acevedo-Siaca, Francisco Pinto, Gemma Molero, Matthew Paul Reynolds, Erik Murchie

مصطلحات موضوعية: Nocturnal Respiration, Temperature Free-Air Controlled Enhancement, info:eu-repo/classification/cti/6, info:eu-repo/classification/agrovoc/NIGHT-TIME, info:eu-repo/classification/agrovoc/RESPIRATION, info:eu-repo/classification/agrovoc/STOMATAL CONDUCTANCE, info:eu-repo/classification/agrovoc/TEMPERATURE, info:eu-repo/classification/agrovoc/WHEAT, info:eu-repo/classification/agrovoc/YIELDS

وصف الملف: application/pdf

العلاقة: https://hdl.handle.net/10883/22662Test

الإتاحة: https://hdl.handle.net/10883/22662Test

المؤلفون: Erik H. Murchie, Kellie E. Smith, Lorna McAusland, John N Ferguson, Zoe A. Wilson, Adam H. Price

المصدر: The Plant Journal. 104:839-855

مصطلحات موضوعية: 0106 biological sciences, 0301 basic medicine, Photosystem II, Plant Science, Biology, Photosynthesis, Models, Biological, 01 natural sciences, 03 medical and health sciences, Genetic variation, Respiration, Genetics, Chlorophyll fluorescence, Oryza sativa, Temperature, Genetic Variation, Photosystem II Protein Complex, food and beverages, Oryza, Cell Biology, Photosynthetic capacity, Plant Leaves, Heat tolerance, Horticulture, 030104 developmental biology, Heat-Shock Response, 010606 plant biology & botany

الوصف: A key target for the improvement of Oryza sativa (rice) is the development of heat-tolerant varieties. This necessitates the development of high-throughput methodologies for the screening of heat tolerance. Progress has been made to this end via visual scoring and chlorophyll fluorescence; however, these approaches demand large infrastructural investments to expose large populations of adult plants to heat stress. To address this bottleneck, we investigated the response of the maximum quantum efficiency of photosystem II (PSII) to rapidly increasing temperatures in excised leaf segments of juvenile rice plants. Segmented models explained the majority of the observed variation in response. Coefficients from these models, i.e. critical temperature (Tcrit ) and the initial response (m1 ), were evaluated for their usability for forecasting adult heat tolerance, measured as the vegetative heat tolerance of adult rice plants through visual (stay-green) and chlorophyll fluorescence (ɸPSII) approaches. We detected substantial variation in heat tolerance of a randomly selected set of indica rice varieties. Both Tcrit and m1 were associated with measured heat tolerance in adult plants, highlighting their usability as high-throughput proxies. Variation in heat tolerance was associated with daytime respiration but not with photosynthetic capacity, highlighting a role for the non-photorespiratory release of CO2 in heat tolerance. To date, this represents the first published instance of genetic variation in these key gas-exchange traits being quantified in response to heat stress in a diverse set of rice accessions. These results outline an efficient strategy for screening heat tolerance and accentuate the need to focus on reduced rates of respiration to improve heat tolerance in rice.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::5df660fa67fe19496144ec0365f85337Test
https://doi.org/10.1111/tpj.14956Test

المؤلفون: Erik H. Murchie, Lorna McAusland, Alexandra J. Burgess

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_________::7e4644e191eed1cd92381ee96229c071Test
https://doi.org/10.1016/b978-0-12-823781-6.00011-3Test

المؤلفون: Erik H Murchie, Matthew Reynolds, Gustavo A Slafer, M John Foulkes, Liana Acevedo-Siaca, Lorna McAusland, Robert Sharwood, Simon Griffiths, Richard B Flavell, Jeff Gwyn, Mark Sawkins, Elizabete Carmo-Silva

مصطلحات موضوعية: Physiology, Source–sink, Plant Science, Biomass, Breeding, Photosynthesis, Yield physiology

الوصف: Source traits are currently of great interest for the enhancement of yield potential; for example, much effort is being expended to find ways of modifying photosynthesis. However, photosynthesis is but one component of crop regulation, so sink activities and the coordination of diverse processes throughout the crop must be considered in an integrated, systems approach. A set of ‘wiring diagrams’ has been devised as a visual tool to integrate the interactions of component processes at different stages of wheat development. They enable the roles of chloroplast, leaf, and whole-canopy processes to be seen in the context of sink development and crop growth as a whole. In this review, we dissect source traits both anatomically (foliar and non-foliar) and temporally (pre- and post-anthesis), and consider the evidence for their regulation at local and whole-plant/crop levels. We consider how the formation of a canopy creates challenges (self-occlusion) and opportunities (dynamic photosynthesis) for components of photosynthesis. Lastly, we discuss the regulation of source activity by feedback regulation. The review is written in the framework of the wiring diagrams which, as integrated descriptors of traits underpinning grain yield, are designed to provide a potential workspace for breeders and other crop scientists that, along with high-throughput and precision phenotyping data, genetics, and bioinformatics, will help build future dynamic models of trait and gene interactions to achieve yield gains in wheat and other field crops. Research of the authors on physiology and genetics of wheat yield potential has been funded by many different sources over the years. Recent grants include the International Wheat Yield Partnership (IWYP) projects funded by the Biotechnology and Biological Research Council of the UK [BB/N021061/1, BB/ N020871/2, BB/S005072/1] (IWYP48, IWYP64, IWYP163 and IWYP25FP, respectively), as well as projects funded by other donors (State Research Agency of Spain: AGL2015-69595-R and RTI2018-096213-B-100).

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=doi_dedup___::079fdee88a3a3e2e50a403fea417a22eTest
https://hdl.handle.net/10459.1/85301Test