29 research outputs found
Tephritid-microbial interactions to enhance fruit fly performance in sterile insect technique programs
Background: The Sterile Insect Technique (SIT) is being applied for the management of economically important pest fruit flies (Diptera: Tephritidae) in a number of countries worldwide. The success and cost effectiveness of SIT depends upon the ability of mass-reared sterilized male insects to successfully copulate with conspecific wild fertile females when released in the field. Methods: We conducted a critical analysis of the literature about the tephritid gut microbiome including the advancement of methods for the identification and characterization of microbiota, particularly next generation sequencing, the impacts of irradiation (to induce sterility of flies) and fruit fly rearing, and the use of probiotics to manipulate the fruit fly gut microbiota. Results: Domestication, mass-rearing, irradiation and handling, as required in SIT, may change the structure of the fruit fliesâ gut microbial community compared to that of wild flies under field conditions. Gut microbiota of tephritids are important in their hostsâ development, performance and physiology. Knowledge of how mass-rearing and associated changes of the microbial community impact the functional role of the bacteria and host biology is limited. Probiotics offer potential to encourage a gut microbial community that limits pathogens, and improves the quality of fruit flies. Conclusions: Advances in technologies used to identify and characterize the gut microbiota will continue to expand our understanding of tephritid gut microbial diversity and community composition. Knowledge about the functions of gut microbes will increase through the use of gnotobiotic models, genome sequencing, metagenomics, metatranscriptomics, metabolomics and metaproteomics. The use of probiotics, or manipulation of the gut microbiota, offers significant opportunities to enhance the production of high quality, performing fruit flies in operational SIT programs
Small Change: Economics and the British coin-tree
This is the accepted manuscript for the following article: Ceri Houlbrook, âSmall Change: Economics and the British coin-treeâ, Post Medieval Archaeology, Vol. 49(1), June 2015. The final published version can be found at: http://www.tandfonline.com/doi/full/10.1179/0079423615Z.00000000074 © Society for Post-Medieval Archaeology 2015Throughout the c.2000 year period coins have been circulated in Britain, they have also been ritually employed, most notably as votive deposits. Focusing specifically on the understudied custom of the British coin-tree, whereby coins are ritually embedded into the barks of trees, this paper considers the coinâs role and applicability as a deposit. It aims to demonstrate that our understanding of the coinâs past, present, and future ritual employment is not only aided by a consideration of economics and the coinâs secular function; it would be utterly incomplete without it.Peer reviewedFinal Accepted Versio
Limited diversity associated with duplicated class II MHC-DRB genes in the red squirrel population in the United Kingdom compared with continental Europe
The red squirrel (Sciurus vulgaris) population in the United Kingdom has declined over the last century and is now on the UK endangered species list. This is the result of competition from the eastern grey squirrel (S. carolinensis) which was introduced in the 19th century. However, recent evidence suggests that the rate of population decline is enhanced by squirrelpox disease, caused by a viral infection carried asymptomatically by grey squirrels but to which red squirrels are highly susceptible. Population genetic diversity provides some resilience to rapidly evolving or exotic pathogens. There is currently no data on genetic diversity of extant UK squirrel populations with respect to genes involved in disease resistance. Diversity is highest at loci involved in the immune response including genes clustered within the major histocompatibility complex (MHC). Using the class II DRB locus as a marker for diversity across the MHC region we genotyped 110 red squirrels from locations in the UK and continentalEurope. Twenty four Scvu-DRB alleles at two functional loci; Scvu-DRB1 and Scvu- DRB2, were identified. High levels of diversity were identified at both loci in the continental populations. In contrast, no diversity was observed at the Scvu-DRB2 locus in the mainland UK population while a high level of homozygosity was observed at the Scvu-DRB1 locus. The red squirrel population in the UK appears to lack the extensive MHC diversity associated with continental populations, a feature which may have contributed to their rapid decline
A comparison of new and existing rootstocks to reduce canker of apple trees caused by Neonectria ditissima (Nectriaceae, Hypocreales)
Abstract The grafting of apple rootstocks on to scions confers benefits including reduced tree size/dwarfing for trellis based growing systems, increased tolerance to physiological stress, and pest and disease management. The current study investigated the effect of rootstock selection on canker and tree death using eight common rootstocks M9 337, M9 337 with Golden Delicious (GD) interstock, M9 EMLA, MM106, M116, M26, GenevaÂź G11 and G41, in addition to six advanced selections from the NIAB East Malling apple breeding programme EMR-001âEMR-006, all grafted with Gala scions. One of the rootstocks, M9 377 was also grafted with a GD interstock. Two locations in England were selected, the first at East Malling, Kent, the second, at Newent, Gloucestershire. Several variables were analysed including cumulative numbers of dead trees per rootstock from 2017 to 2020, number of rootstock âA typeâ cankers, number of scion mainstem âB typeâ cankers, and number of peripheral âCâ+âDâ+âEâ branch cankers at the Kent and Gloucestershire locations in the fourth and final assessment year of 2020. Kendallâs rank correlation was used to test if trunk circumference (a measure of tree vigour) and canker were statistically dependant. Results showed that in Kent, there were significant differences between rootstocks for scion B cankers and peripheral Câ+âDâ+âE cankers. There were no significant differences found between rootstocks for rootstock A cankers at Kent, or any of the three canker types in Gloucestershire. There were up to 31.25% dead trees in Kent (EMR-004), and 30% in Gloucestershire (M9 337 with GD interstock, M26), but there were no significant differences in number of dead trees due to rootstock type in either Kent or Gloucestershire. The Kendallâs rank correlation analysis indicated there was almost no dependence of trunk circumference on canker. The three rootstocks with the overall lowest susceptibility to canker were M116, EMR-006, and EMR-004. The industry standard rootstocks M9 EMLA and M9 337 were ranked 12 and 14, and with EMR-001 were the three worst performing rootstocks. The GenevaÂź rootstocks G11 was ranked 6, and G41 was ranked 11. An interplay of factors are likely involved in the development of canker including location and environmental effectsârainfall, relative humidity, temperature, wind, soil type, topography, aspect, and other seasonal infection processes including pathogen inoculum load, and rainsplash of inoculum between trees and within individual trees, the genetics and physiology of each scion/rootstock combination, water and nutritional status of trees, hormonal and molecular signalling, and orchard management including pruning and removal of cankers
Diversity of Phytophthora Species Detected in Disturbed and Undisturbed British Soils Using High-Throughput Sequencing Targeting ITS rRNA and COI mtDNA Regions
This article belongs to the Special Issue Role of Human Interventions in Spread of Soilborne Forest Pathogens and Methods for Mitigation.Disease outbreaks caused by introduced Phytophthora species have been increasing in British forests and woodlands in recent years. A better knowledge of the Phytophthora communities already present in the UK is of great importance when developing management and mitigation strategies for these diseases. To do this, soils were sampled in âdisturbedâ sites, meaning sites frequently visited by the public, with recent and new plantings or soil disturbances versus more ânaturalâ forest and woodland sites with little disturbance or management. Phytophthora diversity was assessed using high-throughput Illumina sequencing targeting the widely accepted barcoding Internal Transcribed Spacer 1 (ITS1) region of rRNA and comparing it with the mitochondrial cytochrome c oxidase I (COI) gene. Isolation of Phytophthora was run in parallel. Nothophytophthora spp. and Phytophthora spp. were detected in 79 and 41 of the 132 locations of the 14 studied sites when using ITS or COI, respectively. A total of 20 Phytophthora amplicon sequence variants (ASVs) were assigned to known Phytophthora species from eight clades (1a, 2, 2b, 3a, 5, 6b, 7a, 8b, 8c, 8d, 10a, and 10b) and 12 ASVs from six clades (1a, 2c, 3a, 3b, 6b, 7a, 8b, 8c, and 8d) when using ITS or COI, respectively. Only at two locations were the results in agreement for ITS, COI, and isolation. Additionally, 21 and 17 unknown Phytophthora phylotypes were detected using the ITS and COI, respectively. Several Phytophthora spp. within clades 7 and 8, including very important forest pathogens such as P. austrocedri and P. ramorum, were identified and found more frequently at âdisturbedâ sites. Additionally, eight ASVs identified as Nothophytophthora spp. were detected representing the first report of species within this new genus in Britain. Only three species not known to be present in Britain (P. castaneae, P. capsici, and P. fallax) were detected with the ITS primers and not with COI. To confirm the presence of these or any potential new Phytophthora species, sites should be re-sampled for confirmation. Additionally, there is a need to confirm if these species are a threat to British trees and try to establish any eradication measures required to mitigate Phytophthora spread in Britain.This work has received funding from the European Unionâs Horizon 2020 research and innovation programme under grant agreement No 635646, POnTE (Pest Organisms Threatening Europe)
Current status of the Botryosphaeriaceae in Australia
The Botryosphaeriales, and in particular the Botryosphaeriaceae, are a well-studied group of fungi best known for the canker diseases they cause on woody hosts especially in stressed or damaged trees. Australian Plant Pathology herbaria contain many records for this group, but due to considerable taxonomic changes over the past decade, many of the species names have since been reclassified. In this article we used all published records with available sequence data of the Botryosphaeriaceae in Australia to examine the distribution and host range of these taxa. There are 24 genera encompassing 222 species in the Botryosphaeriaceae; 9 genera and 62 species have been recorded in Australia. Some genera such as Neoscytalidium are only found in warm, humid climates while Dothiorella species are more common in temperate climates. There were species, such as Lasiodiplodia theobromae, Neofusicoccum parvum and Botryosphaeria dothidea, which had a wide host range with many records. However, there were also several species found only in one location on a single host. While systematic data collection is still required, the information presented here provides a baseline of species present in Australia and will underpin future studies into this group of important pathogens
Spatial mobility, workers and jobs : perspectives from the Northern Ireland experience
Shuttleworth I. and Green A. E. Spatial mobility, workers and jobs: perspectives from the Northern Ireland experience, Regional Studies. How best to address local concentrations of worklessness is a key question for labour market, economic development and social inclusion policy. Historically, initiatives in Northern Ireland have focused on moving 'jobs to workers', but in changed political circumstances there is now greater emphasis on encouraging the movement of 'workers to jobs'. A review of the Northern Ireland experience in the context of broader consideration of the geography and socio-institutional structure of local labour markets sheds light on the difficulties and successes in implementing both approaches. It is concluded that both have a role to play because labour market space is simultaneously 'segmented' and 'seamless'