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The extent and severity of wheat take-all (caused by Gaeumannomyces graminis var. tritici (Ggt)) can vary considerably between growing seasons. The current study aimed to identify climatic factors associated with differing concentrations of Ggt DNA in soil and take-all disease at different stages of a sequence of wheat crops. Pre-sowing soil Ggt DNA concentrations and subsequent take-all disease in consecutive wheat crop sequences were compared across six seasons in 90 commercial cropping fields in Canterbury and Southland, New Zealand, between 2003 and 2009. Disease progress was assessed in additional fields in 2004/05 and 2005/06. While a general pattern in inoculum and disease fluctuations was evident, there were exceptions among wheat crop sequences that commenced in different years, especially for first wheat crops. In three consecutive growing seasons, there was very low inoculum increase in the first wheat crop, while increases in first wheat crops during the following three seasons was much greater. Low spring–summer rainfall was associated with low build-up of inoculum in first wheat crops. The inoculum derived from the first wheat then determined the amount of primary inoculum for the subsequent second wheat, thereby influencing the severity of take-all in that crop. Differing combinations of weather conditions during one wheat crop in a sequence and the conditions experienced by the next crop provided explanations of the severity of take-all at grain fill and the resulting post-harvest soil Ggt DNA concentrations in second wheat crops. Examples of contrasting combinations were: (a) a moderate take-all epidemic and high post-harvest inoculum that followed high rainfall during grain fill, despite low pre-sowing soil Ggt DNA concentrations; (b) severe take-all and moderate to high inoculum build-up following high pre-sowing soil Ggt DNA concentrations and non-limiting rainfall; and (c) low spring and early summer rainfall slowing epidemic development in second wheat crops, even where there were high pre-sowing soil Ggt DNA concentrations. The importance of the environmental conditions experienced during a particular growing season was also illustrated by differences between growing seasons in take-all progress in fields in the same take-all risk categories based on pre-sowing soil Ggt DNA concentrations.

In response to the confirmed detection of the light brown apple moth, Epiphyas postvittana, in California, approximately 53,000 pheromone-baited Jackson traps were deployed and more than 246,000 males were caught (February 2007–February 2010). Approximately 46,000 manually entered catch records were corrected for errors and converted into catch per trap per day. As empty trap data (zeros) were not recorded, we added zeros between first and last catch for each trap based on the stated servicing period (~30,000), before analyzing for trends. Residual data error rate was estimated as 1.5 %. San Francisco and Santa Cruz counties had relatively high trap catches immediately upon trap set, and remained the leading population centers, while most other counties showed a more general trend of a slow build-up in catch over time (12 counties). An exponential increase in trap catch was observed in four counties with sufficient data. The pattern of spread indicated natural, as well as anthropogenic-assisted spread rates, with populations appearing well ahead of the invasion front. This jump dispersal is probably due to movement of host plants, unsurprising since eggs of this polyphagous moth are readily laid on foliage. There was evidence of seasonality in spread, probably linked to the phenology of the insect. There was a positive relationship between catch and known host tree preference, suggesting that trap placement in preferred hosts could add sensitivity to future surveys. Recommendations include the improved provision of data acquisition by telecommunications, standardization of data input, more archiving, and frequent analysis of trap catches. The rapid rate of population growth demonstrated in two counties and spread across many others supports the hypothesis of the recent arrival of E. postvittana in California.

Researchers report the detection of an X-ray afterglow associated with the gamma-ray burst of Feb 28, 1997--the first such detection for any gamma-ray burst. The X-ray transient was found to contain a significant fraction of the total energy of the gamma-ray burst.

Symptoms of yellow dwarf disease caused by Luteoviridae viruses (YDV) in each of 43–75 autumn-sown wheat crops per year were monitored for six years during 1998–2005 in Canterbury, New Zealand. They were related to seed and foliar insecticide applications and the numbers of YDV aphid vectors from one to four regional 7.5 m high suction traps during the crop emergence–GS 30 virus infection-risk period. Over the five years when YDV was assessed in each crop on visual symptoms at flag leaf, the YDV incidence in untreated crops tended to increase with increasing numbers of flying aphids. When aphid numbers were below a relatively low threshold during the risk period for each crop, YDV incidence was low irrespective of insecticide treatments. Above this aphid threshold, the incidence of YDV was lowest in crops with an insecticide programme of an imidacloprid seed treatment followed by one foliar application of lambda-cyhalothrin at 17–24 g ai ha−1. This regime was estimated to provide protection from aphid-transmitted virus infection for approximately 50 % of the risk period irrespective of sowing date. Wheat crops treated with an imidacloprid-seed treatment plus one insecticide foliar application had 96 % less virus incidence than untreated crops, and one foliar application alone had 70 % less incidence. These results suggest that a tool incorporating aphid flight patterns and wheat growth stages could be developed to optimise insecticide applications for control of secondary aphid incursions in autumn sown wheat crops in New Zealand.

Development of sustainable‐crop production systems depends on identifying effective strategies for the management of postharvest crop residues. The effects of time‐of‐incorporation (autumn‐incorporated [AI] vs. spring‐incorporated [SI] and irrigation (irrigated[Irr] vs. nonirrigated[Nirr]) on barley Hordeum vulgare L. straw decomposition and microbial activity were investigated in relation to soil N availability and crop production over one cropping cycle in Canterbury, New Zealand. Over the winter‐fallow period, the weight loss of AI barley straw averaged 33% as compared with 18% for surface straw of SI treatments. By harvest, nearly all of the difference in mass loss between AI and SI straw (17%) from NIrr treatments could be attributed to decomposition in the fallow period. Irrigation increased straw decomposition during the cropping period by 68% in AI treatment compared with only 37% in SI treatment. The effect of winter‐straw placement on the response of barley straw to summer irrigation was related to the size of the residue‐borne microbial populations at the start of the cropping period. Although relatively little N was released (<5 kg N ha−1) from decaying barley straw, cultivation, and incorporation of straw in autumn (AI) did result in greater topsoil (0–25 cm) mineral N levels during the winter period as compared with the SI treatment. Overall, Irr and AI of straw increased the dry matter production and N uptake of the summer barley crop, resulting in a concomitant decrease in soil mineral N levels relative to Nirr SI treatments. The mechanisms that explain this difference in crop response to winter residue management require further investigation.

We present the first reported case in the English language literature of an inflammatory myofibroblastic tumour of the right tonsil in a young, pregnant woman, and we report a management strategy for this enigmatic entity. A 28-year-old, pregnant woman presented with a 10-day history of odynophagia despite a course of antibiotics. Examination revealed a grade II, erythematous right tonsil with ulceration on the upper pole. A biopsy was arranged, and initial evaluation was suggestive of spindle cell carcinoma. However, this diagnosis was reviewed after immunohistochemical staining confirmed an inflammatory myofibroblastic tumour. Subsequent complete excision was undertaken using CO2 laser. Clinically, inflammatory myofibroblastic tumour of the tonsil is known to be locally aggressive and can present in a manner not dissimilar to a high grade carcinoma of the tonsil. As a result, the recommended treatment is complete local excision with careful follow up.

Introduction and ObjectivesSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the current coronavirus disease 2019 (COVID-19) pandemic. Whilst a substantial proportion of adults infected with SARS-CoV-2 progress to develop severe disease, children rarely manifest respiratory complications. However, the underlying mechanism behind this disparity remains largely unknown. Understanding the differences in the local and systemic response to SARS-CoV-2 infection at single cell resolution between children and adults may offer key clues about the pathogenesis of SARS-CoV-2 infection, providing guidance for future therapies and treatments.MethodsTo address this we generated a healthy reference multi-omics single cell data set from children (n=30) from infancy to adulthood (n=11). Here we profiled triple matched samples: nasal and tracheal brushings and PBMCs for single cell analysis, where we tracked the developmental changes for 59 airway and 45 blood cell populations at both transcriptomic and proteomic level. These were then contrasted with equivalent data from paediatric and adult COVID-19+ patients collected across a range of disease severities (total n=32), enabling age and disease-specific variances to be analysed at single cell level.ResultsStriking differences within the paediatric and adult immune responses in COVID-19 were observed, including an overall weaker interferon-response signature, with fewer interferon-stimulated immune cell subpopulations within children infected by SARS-CoV-2 compared to adults. In peripheral blood, a greater proportion of naïve cell populations was observed with disease, with the response in adults primarily dominated by the adaptive immune system. In the airway epithelium, we found the highest viral load in goblet and ciliated cells in infected adults and most notably, described a novel inflammatory epithelial cell population, enriched within our COVID-19 patients, representing a transitional regenerative state between secretory and ciliated cells. Through the integration of matched blood and airway samples we were able to investigate the dynamics between local and systemic response to COVID-19, finding marked differences.Abstract T1 Figure 1ConclusionsOverall, this largest paediatric single cell COVID-19 study to date showed significant differences in response to SARS-CoV-2 between children and adults, reflecting the changes of the immune landscape over developmental time, which in children are dominated by naïve and innate responses.

Hordeum vulgare (cultivated barley) x H. bulbosum (bulbous barley grass) hybrids have been used to obtain disease-resistant recombinant lines (RLs). The RLs contain chromatin transferred from the wild species mostly onto the long arms of recipient barley chromosomes. To determine whether differences in meiotic metaphase I (MI) associations between the long and short arms of homoeologous chromosomes can account for the preponderance of introgressions on the long arms, we carried out fluorescent in situ hybridisation on MI chromosome preparations obtained from pollen mother cells of a diploid interspecific hybrid. By using various probes, we established that MI associations between the long arms occurred more frequently than between the short arms for the five chromosomes tested.

The soil-borne ascomycete Gaeumannomyces graminis var. tritici causes take-all of wheat (Triticum aestivum). Between host crops, G. graminis var. tritici survives saprophytically on crop debris and by infecting susceptible grass weeds or cereal volunteers. Invasion of roots in the following wheat crop results in reduced grain yield and quality. Take-all is commonly assessed in the field by visual inspection. Molecular-based methods are also available to detect G. graminis var. tritici, including a quantitative PCR (qPCR) assay that indirectly measures the amount of pathogen DNA in environmental samples. The qPCR is used as part of a commercial tool (known as PreDicta B™) to predict the risks of take-all in wheat crops prior to planting, which are dependent on the amount of Gaeumannomyces inoculum in field soils. Unfortunately, the costs associated with the PreDicta B™ test can be prohibitive to its use. As a result, in this study, an alternative qPCR assay was developed to measure directly the DNA of G. graminis var. tritici. The assay was shown to detect DNA of G. graminis var. tritici in both symptomatic and non-symptomatic wheat roots, with an increase in the amount of DNA detected having a strong relationship with an increase in take-all symptoms.