18 research outputs found
Characterization of chilling-shock responses in four genotypes of Miscanthus reveals the superior tolerance of M. Ă giganteus compared with M. sinensis and M. sacchariflorus
Abstract
Background and Aims
The bioenergy grass Miscanthus is native to eastern Asia. As Miscanthus uses C4 photosynthesis, the cooler temperatures experienced in much of northern Europe are expected to limit productivity. Identification of genetic diversity in chilling tolerance will enable breeders to generate more productive varieties for these cooler regions. Characterizing the temporal relationships between photosynthesis, carbohydrate and molecular expression of relevant genes is key to understanding genotypic differences in tolerance or sensitivity.
Methods
To characterize chilling responses in four Miscanthus genotypes, plants were exposed to a sudden reduction in temperature. The genotypes studied comprised of two M. sinensis, one M. sacchariflorus and one inter-species hybrid, M. Ă giganteus. Changes in photosynthesis (Asat), carbohydrate composition and the expression of target transcripts were observed following chilling-shock. After 4 d the decline in leaf elongation rate (LER) in the different genotypes was measured.
Results
Following chilling-shock the greatest decline in Asat was observed in M. sacchariflorus and one M. sinensis genotype. Carbohydrate concentrations increased in all genotypes following chilling but to a lesser extent in M. sacchariflorus. Two stress inducible genes were most highly expressed in the genotypes that experienced the greatest declines in Asat and LER. Miscanthus à giganteus retained the highest Asat and was unique in exhibiting no decline in LER following transfer to 12 °C.
Conclusions
Miscanthus Ă giganteus exhibits a superior tolerance to chilling shock than other genotypes of Miscanthus. The absence of sucrose accumulation in M. sacchariflorus during chilling-shock suggests an impairment in enzyme function. A candidate transcription factor, MsCBF3, is most highly expressed in the most sensitive genotypes and may be a suitable molecular marker for predicting chilling sensitivity
Seasonal Carbohydrate Dynamics and Climatic Regulation of Senescence in the Perennial Grass, Miscanthus
Miscanthus is a perennial energy grass predominantly used for combustion but there is increasing interest in fermenting the cell-wall carbohydrates or green-cutting for soluble sugars to produce bioethanol. Our aims were to: (1) quantify non-structural carbohydrates (NSC), (2) observe the timing of seasonal shifts in the stems and rhizome, and (3) identify developmental and/or climatic conditions that promoted carbohydrate remobilization from the stems to the rhizome during senescence. Two genotypes of Miscanthus sinensis, a Miscanthus sacchariflorus and a Miscanthus Ă giganteus were grown at replicated field sites in Aberystwyth, West Wales and Harpenden, South East England. NSC were quantified from the rhizome and aboveground organs and then correlated with climatic data collected from on-site weather stations. PAR and maximum daily temperatures were higher at Harpenden throughout the year, but daily minimum temperatures were lower. Senescence was accelerated at Harpenden. Carbohydrates were retained within the stems of non-flowering genotypes, at both sites, in winter and were still present after a frost event to â2 °C. Rhizome starch concentrations were at least equal to the previous winterâs levels (February 2011) by September. Lower daily minimum temperatures accelerate the rate of senescence and warmer daily maximum temperatures cannot counteract this effect. At current yields, M. Ă giganteus, could produce 0.7 t haâ1 of NSC in addition to ligno-cellulosic biomass in November but with concerted breeding efforts this could be targeted for improvement as has been achieved in other crops. Shifting harvests forward to November would not leave the rhizome depleted of carbohydrates
QTL analysis for sugar-regulated senescence suppports flowering-dependent and - independent senescence pathways
CATALISE: A multinational and multidisciplinary Delphi consensus study. Identifying language impairments in children
Delayed or impaired language development is a common developmental concern, yet thereis little agreement about the criteria used to identify and classify language impairments inchildren. Children's language difficulties are at the interface between education, medicineand the allied professions, who may all adopt different approaches to conceptualising them.Our goal in this study was to use an online Delphi technique to see whether it was possibleto achieve consensus among professionals on appropriate criteria for identifying childrenwho might benefit from specialist services. We recruited a panel of 59 experts representingten disciplines (including education, psychology, speech-language therapy/pathology, paediatricsand child psychiatry) from English-speaking countries (Australia, Canada, Ireland,New Zealand, United Kingdom and USA). The starting point for round 1 was a set of 46statements based on articles and commentaries in a special issue of a journal focusing onthis topic. Panel members rated each statement for both relevance and validity on a sevenpointscale, and added free text comments. These responses were synthesised by the firsttwo authors, who then removed, combined or modified items with a view to improving consensus.The resulting set of statements was returned to the panel for a second evaluation(round 2). Consensus (percentage reporting 'agree' or 'strongly agree') was at least 80 percentfor 24 of 27 round 2 statements, though many respondents qualified their responsewith written comments. These were again synthesised by the first two authors. The resultingconsensus statement is reported here, with additional summary of relevant evidence, and aconcluding commentary on residual disagreements and gaps in the evidence base.</p
An immune dysfunction score for stratification of patients with acute infection based on whole-blood gene expression
Dysregulated host responses to infection can lead to organ dysfunction and sepsis, causing millions of global deaths each year. To alleviate this burden, improved prognostication and biomarkers of response are urgently needed. We investigated the use of whole-blood transcriptomics for stratification of patients with severe infection by integrating data from 3149 samples from patients with sepsis due to community-acquired pneumonia or fecal peritonitis admitted to intensive care and healthy individuals into a gene expression reference map. We used this map to derive a quantitative sepsis response signature (SRSq) score reflective of immune dysfunction and predictive of clinical outcomes, which can be estimated using a 7- or 12-gene signature. Last, we built a machine learning framework, SepstratifieR, to deploy SRSq in adult and pediatric bacterial and viral sepsis, H1N1 influenza, and COVID-19, demonstrating clinically relevant stratification across diseases and revealing some of the physiological alterations linking immune dysregulation to mortality. Our method enables early identification of individuals with dysfunctional immune profiles, bringing us closer to precision medicine in infection.peer-reviewe
Phase 2 of CATALISE: a multinational and multidisciplinary Delphi consensus study of problems with language development: Terminology.
Background: Lack
of agreement about criteria and terminology for childrenâs language problems
affects access to services as well as hindering research and practice. We
report the second phase of a study using an online Delphi method to address
these issues. In the first phase, we focused on criteria for language disorder.
Here we consider terminology.Methods: The Delphi
method is an iterative process in which an initial set of statements is rated
by a panel of experts, who then have the opportunity to view anonymised ratings
from other panel members. On this basis they can either revise their views or
make a case for their position. The statements are then revised based on panel feedback,
and again rated by and commented on by the panel. In this study, feedback from
a second round was used to prepare a final set of statements in narrative form.
The panel included 57 individuals representing a range of professions and
nationalities. Results: We achieved
at least 78% agreement for 19 of 21 statements within two rounds of ratings.
These were collapsed into 12 statements for the final consensus reported here.
The term âLanguage Disorderâ is recommended to refer to a profile of
difficulties that causes functional impairment in everyday life and is associated
with poor prognosis. The term, âDevelopmental Language Disorderâ (DLD) was
endorsed for use when the language disorder was not associated with a known
biomedical aetiology. It was also agreed that (a) presence of risk factors
(neurobiological or environmental) does not preclude a diagnosis of DLD, (b)
DLD can co-occur with other neurodevelopmental disorders (e.g. ADHD) and (c)
DLD does not require a mismatch between verbal and nonverbal ability. Conclusions:
This Delphi exercise highlights reasons for disagreements about
terminology for language disorders and proposes standard definitions and
nomenclature.
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A nuclear-localized protein, KOLD SENSITIV-1, affects the expression of cold-responsive genes during prolonged chilling in Arabidopsis
A pseudo-3D model to optimise the target traits of light interception in short-rotation coppice willow
A One-Step Grafting Methodology Can Adjust Stem Morphology and Increase THCA Yield in Medicinal Cannabis
The standard two-step methods for grafting horticultural crops involve cultivating the rootstock for a period of time and then connecting the scion. Medicinal Cannabis differs from most annual horticultural crops because it is usually clonally propagated from cuttings. We developed a grafting methodology specifically for medicinal Cannabis, involving a single step, in which a freshly cut scion is grafted to a freshly cut donor stem that will become the rootstock. This study also aimed to uncover a potential role for roots in influencing cannabinoid content. Two varieties with desirable attributes but cultivation limitations were selected to act as scions. The first, “CBD1” was a high CBDA accumulating variety with low biomass yield, and the second, “THC2”, was a high yielding, high THCA accumulating line with inconsistent root development during cloning. Two candidate rootstocks, “THC9r” and “THC8r”, were identified; both were high THCA, low CBDA varieties. Biomass yields in the THC2 scions grafted to THC9 rootstocks (THC9r_2s) were 20% higher than in the non-grafted THC2 plants. In CBD1 grafted plants, the concentrations of CBDA and some minor cannabinoids were significantly different to non-grafted CBD1, but biomass yields were lower. There was a trend towards a higher concentration of THCA in THC9r_2s plants, and when combined with the increased biomass, yield of THCA was increased from 8 g Plant−1 to 13 g Plant−1. Our results present a new grafting method for medicinal Cannabis that improved yield in THC2 and required no additional cultivation time
A One-Step Grafting Methodology Can Adjust Stem Morphology and Increase THCA Yield in Medicinal Cannabis
The standard two-step methods for grafting horticultural crops involve cultivating the rootstock for a period of time and then connecting the scion. Medicinal Cannabis differs from most annual horticultural crops because it is usually clonally propagated from cuttings. We developed a grafting methodology specifically for medicinal Cannabis, involving a single step, in which a freshly cut scion is grafted to a freshly cut donor stem that will become the rootstock. This study also aimed to uncover a potential role for roots in influencing cannabinoid content. Two varieties with desirable attributes but cultivation limitations were selected to act as scions. The first, âCBD1â was a high CBDA accumulating variety with low biomass yield, and the second, âTHC2â, was a high yielding, high THCA accumulating line with inconsistent root development during cloning. Two candidate rootstocks, âTHC9râ and âTHC8râ, were identified; both were high THCA, low CBDA varieties. Biomass yields in the THC2 scions grafted to THC9 rootstocks (THC9r_2s) were 20% higher than in the non-grafted THC2 plants. In CBD1 grafted plants, the concentrations of CBDA and some minor cannabinoids were significantly different to non-grafted CBD1, but biomass yields were lower. There was a trend towards a higher concentration of THCA in THC9r_2s plants, and when combined with the increased biomass, yield of THCA was increased from 8 g Plantâ1 to 13 g Plantâ1. Our results present a new grafting method for medicinal Cannabis that improved yield in THC2 and required no additional cultivation time