Aluminium (Al) toxicity in acid soils continues to be a major concern for crop production, especially for wheat which is a moderately tolerant cereal crop species. So far, Al tolerance was known to ...be controlled by few genetic loci detected clearly by classical mapping studies. Here, we report the outcome of a genome wide association mapping approach in bread wheat (Triticum aestivum L.) using 525 Diversity Array Technology markers genotyped in a core collection of 96 winter wheat accessions. Marker-trait associations (MTAs) were detected using both general linear model (GLM) and mixed linear model (MLM). Five significant MTAs were identified as shared by models on chromosomes 1A, 1D, 3B and 6A. Highly significant MTAs were identified by MLM on chromosomes 1D and 3B which could be new candidate loci for future studies. Some of our results are in line with prior reports, but some appear to be novel. Potential candidate genes have been searched in respective chromosomal bins for highly significant MTAs detected by MLM. The loci identified in our study have the potential to improve Al tolerance in wheat and hence need to be verified and utilized for breeding tolerant cultivars worldwide.
Greenbug is one of the most aggressive pests of barley and wheat. In Argentina, yield losses of wheat, barley, oat and sorghum crops caused by greenbug are chronic and at times severe. Since Marker ...Assisted selection for greenbug resistance genes in barley is very limited, the purpose of the current study was to map greenbug resistance genes in doubled haploid (DH) lines and to identify candidate genes. A set of DH lines of the Oregon-Wolfe Barley (OWB) mapping population derived from the cross between OWB
DOM
and OWB
REC
and both parental lines were screened for tolerance to greenbug. There was significant variation among the DH lines in foliar area (FA), dry weight (DW) and chlorophyll contents (Ch) between infested and control DH lines. Three main QTLs were identified. These QTLs explained 82 % of the FA, 80 % of DW and 58 % of Ch variability of infested plants. The initial and final FA and DW of controls and final DW of infested plants were associated with the same molecular markers on chromosome 2H (
Vrs1
,
BmAc0144f
,
GBR259
,
GBS705
). The final FA of infested plants was significantly linked to molecular markers on chromosome 5H (
GBRO986
,
GBR518
,
GBM1483
,
GBR1082
). The positive alleles were provided by OWB
DOM
. The content of chlorophyll of infested plants was associated with the marker loci
Ris44
,
GBR1608
,
GBR1637N
and
GBS0785
on chromosome 7H, with the positive alleles provided by OWB
REC
. Both parents contributed to different tolerance traits. The QTLs found in this population are new greenbug resistance loci. A sequence homology search was performed to derive the putative function of the genes linked to the QTLs.
Phytohormones, a group of structurally unrelated small molecules are plant-signalling compounds that trigger induced resistance against certain pathogens and herbivores. The hormones jasmonic acid ...(JA), ABA, salicilic acid (SA) and ethylene (ET) are known to play major roles in regulating plant defence responses. In order to determine the changes in growth and in the chlorophyll content induced by the exogenous application of these elicitors, a set of DH lines of the Oregon-Wolfe Barley mapping population, previously screened to locate aphid resistant genes, was investigated. The aim of the current research was to map the induced defence genes and to reveal the relationship with aphid resistance. There were highly significant differences between controls and hormone treated plants in the aerial fresh and dry weights (AFW, ADW), the foliar area (FA) and the root dry weight (RDW). More than 15 JA and ET-induced lines exceeded the chlorophyll (Ch) values of their controls. Most of the plant traits were associated with the same genetic windows on chromosomes 3H, 5H and 7H in the controls and hormone treated plants. QTL(s) identified on chromosome 3H and 5H explained most of the variation of AFW, ADW, FA and RDW of controls and treated plants. QTL(s) located on chromosome 5H were associated with the variation of chlorophyll contents on JA-treated plants. The Ch in ET and ABA-treated plants was associated with two different regions on chromosome 7H. One of the latter genetic windows also explained the variation of RDW of ET- and ABA-treated plants. A sequence homology search was performed to derive the putative function of the genes linked to the QTLs. Several QTLs were identified located close to aphid resistance genes previously mapped. This is the first report of genes associated with hormone response in barley that could be involved with insect resistance. Those recombinant lines carrying the appropriate alleles could be useful for breeding barley to enlarge the genetic base of defence against stress.
Abstract
This mini-review provides a perspective of traditional, emerging and future applications of lactic acid bacteria (LAB) and how genome editing tools can be used to overcome current challenges ...in all these applications. It also describes available tools and how these can be further developed, and takes current legislation into account. Genome editing tools are necessary for the construction of strains for new applications and products, but can also play a crucial role in traditional ones, such as food and probiotics, as a research tool for gaining mechanistic insights and discovering new properties. Traditionally, recombinant DNA techniques for LAB have strongly focused on being food-grade, but they lack speed and the number of genetically tractable strains is still rather limited. Further tool development will enable rapid construction of multiple mutants or mutant libraries on a genomic level in a wide variety of LAB strains. We also propose an iterative Design–Build–Test–Learn workflow cycle for LAB cell factory development based on systems biology, with ‘cell factory’ expanding beyond its traditional meaning of production strains and making use of genome editing tools to advance LAB understanding, applications and strain development.
Traditional, emerging and future applications of lactic acid bacteria can all benefit from genome editing and a proposed Design–Build–Test–Learn workflow cycle for advancement of strain development.
Bread wheat
Triticum aestivum
L. possesses a genetic variation for the ability to survive and reproduce under salt stress conditions. Durum wheat (
T. durum
Desf.) is in general more sensitive in ...comparison to bread wheat, however, exceptions can be found showing the same extent of salt tolerance. Endemic wheats in general are characterised by a high adaptability to their environment. The level and variability of salt tolerance were assessed in a germplasm collection of 144 winter and spring wheat accessions from Georgia comprising
Triticum aestivum
L.,
T. durum
Desf.,
T. dicoccon
Schrank,
T. polonicum
L. and Georgian endemics:
T. carthlicum
Nevski,
T. karamyschevii
Nevski,
T. macha
Dekapr. et Menabde,
T. timopheevii
(Zhuk.) Zhuk. and
T. zhukovskyi
Menabde et Ericzjan. The accessions were tested for salt tolerance at the germination stage. Large variability in salt tolerance within the Georgian germplasm was found among the different wheat species. The endemic hexaploid winter wheat
T. macha
and the endemic tetraploid wheat
T. timopheevii
were among the most tolerant materials, thus presenting promising donors for salt tolerant traits in future breeding efforts for salinity tolerance in wheat.
The all-sky PLATO input catalogue Montalto, M.; Piotto, G.; Marrese, P. M. ...
Astronomy & astrophysics,
09/2021, Volume:
653
Journal Article
Peer reviewed
Open access
Context.
The ESA PLAnetary Transits and Oscillations of stars (PLATO) mission will search for terrestrial planets in the habitable zone of solar-type stars. Because of telemetry limitations, PLATO ...targets need to be pre-selected.
Aims.
In this paper, we present an all sky catalogue that will be fundamental to selecting the best PLATO fields and the most promising target stars, deriving their basic parameters, analysing the instrumental performances, and then planing and optimising follow-up observations. This catalogue also represents a valuable resource for the general definition of stellar samples optimised for the search of transiting planets.
Methods.
We used
Gaia
Data Release 2 astrometry and photometry and 3D maps of the local interstellar medium to isolate FGK (
V
≤ 13) and M (
V
≤ 16) dwarfs and subgiant stars.
Results.
We present the first public release of the all-sky PLATO input catalogue (asPIC1.1) containing a total of 2 675 539 stars including 2 378 177 FGK dwarfs and subgiants and 297 362 M dwarfs. The median distance in our sample is 428 pc for FGK stars and 146 pc for M dwarfs, respectively. We derived the reddening of our targets and developed an algorithm to estimate stellar fundamental parameters (
T
eff
, radius, mass) from astrometric and photometric measurements.
Conclusions.
We show that the overall (internal+external) uncertainties on the stellar parameter determined in the present study are ∼230 K (4%) for the effective temperatures, ∼0.1
R
⊙
(9%) for the stellar radii, and ∼0.1
M
⊙
(11%) for the stellar mass. We release a special target list containing all known planet hosts cross-matched with our catalogue.
Water kefir is a fermented beverage often produced in a household setting through the inoculation of a microbial community (water kefir grains) into a sugar rich solution. To date, a detailed ...understanding of how this community evolves during the fermentation, and the resulting impact on the final beverage flavour has not been elucidated. To address this metagenomics, flavour analysis and sensory science were used to resolve the temporal evolution of a model water kefir. We observed that the diversity of the water kefir studied is relatively unique, being dominated throughout the fermentation by the gluconic acid producer Zymomonas mobilis. We describe the metagenome-assembled genome of two likely new Curvibacter species, that is mostly found in the liquid fraction. Finally, we show that, in addition to Z. mobilis, members of the Bifidobacterium, Acetobacter and Saccharomyces species as well as former members of the Lactobacillus genus, were the main contributors to flavour.
Water kefir has become an increasingly attractive alternative natural beverage for consumers, while also serving as an interesting model to enhance our understanding of microbial communities consisting of eukaryotes and prokaryotes. By integrating metagenomics, chemical profiling and sensory evaluation, we illustrate and clarify the dynamic nature of water kefir fermentations. In addition to elucidating its detailed temporal diversity, we also highlight the potential flavour and sensory contributions of the different microbial members of the community. These combined findings represent a significant milestone in the understanding of water kefir microbiology while also paving the way for the development of defined starter cultures that can enable the manufacture of a beverage which reproduces the main attributes of a traditionally brewed water kefir.
•Temporal characterization of a model water kefir using multi-omics approach.•High prevalence of Z. mobilis and discovery of two potential new Curvibacter species.•Unique chemical profile, dominated by gluconic acid.•Microbial contributors to water kefir flavours obtained through omics correlation.•Important insights gathered will enable large scale water kefir production.
A collection of 220 accessions of parsley (Petroselinum crispum Mill. Nyman) was evaluated at two experimental stations (Gatersleben and Quedlinburg, Germany) under natural infection. Widespread ...origins of tested accessions provide the opportunity for first-time characterization of existence, spreading and level of resistance/susceptibility to the economically important pathogens Septoria petroselini Desm., Plasmopara petroselini Săvul. et O. Săvul. and Erysiphe heraclei DC. ex Saint-Aman causing Septoria blight, downy mildew and powdery mildew respectively throughout the species P. crispum. For each pathogen, accessions free or nearly free of symptoms were found: S. petroselini: free 1, nearly free 25, P. petroselini: free 51, nearly free 22 and E. heraclei: free 166. Eight accessions are free or nearly free of symptoms for all three pathogens: PET36, PET169, PET172, PET177, PET178, PET192, PET212 and PET214. The accession PET16 is free of symptoms for both S. petroselini and P. petroselini. Most of the resistant material comes from Southern and Eastern Europe. There could be a centre for resistances of parsley.
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