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Lodging is a major constraint to increasing yield in many crops, but is of particular importance in the small-grained cereals. This study investigated the genetic contro! of lodging and component traits in wheat through the detection of utiderlying quantitative trait loci (QTL), The analysis was based on the identittcation of genomic regions which affect various traits related to lodging resistance in a population of 96 doubled haploid lines of the cross 'Milan' x 'Catbird", mapped using 126 microsatellite markers. Although major genes related to plant height (Rhl genes) were responsible for increasing lodging resistanee in this cross, several other traits independenl of plant height were shown to be important such as rool and shoot traits, and various components of plant yield. Yield components sueh as grain number and weight were shown to be an indicator of plant susceptibility to lodging-QTL for lodging and associated traits were found on chromosomes IB, ID. 2B. 2D. 4B, 4D. 6D and 7D. QTL for yield and associated traits were identified on chromosomes IB, ID. 2A. 2B. 2D. 4D and 6A,

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The adaptability of wheat varieties to precise environmental conditions is known to be influenced to a large extent by photoperiod sensitive genes determining ear emergence time and by the gibberelic acid insensitive dwarfing genes that are regularly used to reduce plant height. A range of European winter wheat varieties were examined to establish whether breeders in different countries have selected genotypes carrying allelic variants of photoperiodic and dwarfing genes that would be expected to provide the best levels of adaptability. In most areas modern cultivars were seen to carry the genotypes predicted to promote good levels of adaptability. Varieties cultivated in Germany however are still predominately of conventional height and late flowering lacking genes that would be expected to enhance adaptability and yield.

BackgroundSurveillance of commensal Escherichia coli, a possible reservoir of antimicrobial resistance (AMR) genes, is important as they pose a risk to human and animal health. Most surveillance activities rely on phenotypic characterisation, but whole genome sequencing (WGS) presents an alternative.AimIn this retrospective study, we tested 515 E. coli isolated from pigs to evaluate the use of WGS to predict resistance phenotype.MethodsMinimum inhibitory concentration (MIC) was determined for nine antimicrobials of clinical and veterinary importance. Deviation from wild-type, fully-susceptible MIC was assessed using European Committee on Antimicrobial Susceptibility Testing (EUCAST) epidemiological cut-off (ECOFF) values. Presence of AMR genes and mutations were determined using APHA SeqFinder. Statistical two-by-two table analysis and Cohen’s kappa (k) test were applied to assess genotype and phenotype concordance.ResultsOverall, correlation of WGS with susceptibility to the nine antimicrobials was 98.9% for test specificity, and 97.5% for the positive predictive value of a test. The overall kappa score (k = 0.914) indicated AMR gene presence was highly predictive of reduced susceptibility and showed excellent correlation with MIC. However, there was variation for each antimicrobial; five showed excellent correlation; four very good and one moderate. Suggested ECOFF adjustments increased concordance between genotypic data and kappa values for four antimicrobials.ConclusionWGS is a powerful tool for accurately predicting AMR that can be used for national surveillance purposes. Additionally, it can detect resistance genes from a wider panel of antimicrobials whose phenotypes are currently not monitored but may be of importance in the future.

Rhtl2, a dominant dwarfing gene of wheat, was shown to be located distally on the long arm of chromosome 5A. Lack of recombination with the awn inhibitor Bl suggested that Rhtl2 is either tightly linked to this gene or is, in this material, a pleiotropic expression of the gene. Linkage to ft-Amy-AI was also very tight, indicating that Rhtl2 is present on the segment of chromosome 5 AL ancestrally translocated from 4AL. The close linkage to li-Amy-Al also suggests that RhtI2 is not a homoeoallele of the commercially important GA-insensitive dwarfing genes.Analysis of near-isogenic lines in a number of genetic backgrounds showed that Rhtl2 reduces height without altering ear size and significantly increases spikelet fertility. However its successful utilization in breeding programmes will require careful selection since in some backgrounds the gene reduces grain numbers and grain size. In all backgrounds, Rhtl2 delayed ear emergence time by around 6 days. A delay of this magnitude could, in many environments, adversely affect yield if it is not neutralized by altering the balance of other genes determining ear emergence

Combatting antimicrobial resistant (AMR) using a One-Health approach is essential as various bacteria, including Escherichia coli, a common bacteria, are becoming increasingly resistant and livestock may be a reservoir. The AMR gene content of 492 E. coli, isolated from 56 pig farms across Great Britain in 2014-2015, and purified on antibiotic selective and non-selective plates, was determined using whole genome sequencing (WGS). The E. coli were phylogenetically diverse harboring a variety of AMR profiles with widespread resistance to "old" antibiotics; isolates harbored up to seven plasmid Inc-types. None showed concurrent resistance to third-generation cephalosporins, fluoroquinolones and clinically relevant aminoglycosides, although ∼3% harbored AMR genes to both the former two. Transferable resistance to carbapenem and colistin were absent, and six of 117 E. coli STs belonged to major types associated with human disease. Prevalence of genotypically MDR E. coli, gathered from non-selective media was 46.9% and that of extended-spectrum-beta-lactamase E. coli was low (∼4% from non-selective). Approximately 72.6% of E. coli from ciprofloxacin plates and only 8.5% from the other plates harbored fluoroquinolone resistance due to topoisomerase mutations; the majority were MDR. In fact, multivariable analysis confirmed E. coli purified from CIP enrichment plates were more likely to be MDR, and suggested MDR isolates were also more probable from farms with high antibiotic usage, specialist finisher farms, and farms emptying their manure pits only after each batch. Additionally, farms from the South East were more likely to have MDR E. coli, whereas farms in Yorkshire and the Humber were less likely.