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Zymoseptoria tritici, the causal agent of septoria tritici blotch (STB), remains a significant threat to European wheat production with the continuous emergence of fungicide resistance in Z. tritici strains eroding the economic sustainability of wheat production systems. The life cycle of Z. tritici is characterised by a pre-symptomatic phase (latent period, LP) after which the pathogen switches to an aggressive necrotrophic stage, when lesions bearing pycnidia quickly manifest on the leaf. As minimal knowledge on the possible role of the LP in supporting STB resistance/susceptibility exists, the goal of this study was to investigate the spatial and temporal association between the LP and disease progression across 3 locations (Ireland – Waterford, Carlow; UK – Norwich) that represent commercially high, medium and low STB pressure environments. Completed over two seasons (2013-2015) with commercially grown cultivars, the potential of the LP in stalling STB epidemics was significant as identified with cv. Stigg, whose high level of partial resistance was characterised by a lengthened LP (~36 days) under the high disease pressure environment of Waterford. However, once the LP concluded it was followed by a rate of disease progression in cv. Stigg that was comparable to that observed in the more susceptible commercial varieties. Complementary analysis via logistic modelling of intensive disease assessments made at Carlow and Waterford in 2015, further highlighted the value of a lengthened LP in supporting strong partial resistance against STB disease of wheat. This article is protected by copyright. All rights reserved.

BACKGROUND: Succinate dehydrogenase inhibitor fungicides are important in the management of Zymoseptoria tritici in wheat. New active ingredients from this group of fungicides have been introduced recently and are widely used. Because the fungicides act at a single enzyme site, resistance development in Z. tritici is classified as medium-to-high risk. RESULTS: Isolates from Irish experimental plots in 2015 were tested against the SDHI penthiopyrad during routine monitoring. The median of the population was approximately 2 x less sensitive than the median of the baseline population. Two of the 93 isolates were much less sensitive to penthiopyrad than least sensitive of the baseline isolates. These isolates were also insensitive to most of commercially available SDHIs. Analysis of the succinate dehydrogenase coding genes confirmed the presence of the substitutions SdhC-H152R and SdhD-R47W in the very insensitive isolates. CONCLUSION: This is the first report showing that the SdhC-H152R mutation detected in laboratory mutagenesis studies also exists in the field. The function and relevance of this mutation, combined with SdhD-R47W, still needs to be determined.

Combining fungicides with different modes of action is regarded as one of the most effective means of slowing the selection of resistance. Field trials were used to study the effects of such mixtures on selection for Zymoseptoria tritici with reduced sensitivity to the succinate dehydrogenase inhibitors (SDHIs) and azole fungicides. The SDHI isopyrazam and the azole epoxiconazole were applied individually as solo products, and together in a preformulated mixture. All fungicide treatments were included at both full and half the recommended doses.

The evolution of fungicide resistance in the cereal pathogen Zymoseptoria tritici, is a serious threat to the sustainability and profitability of wheat production in Europe. Application of azole fungicides has been shown to affect fitness of Z. tritici variants differentially, so it has been hypothesised that combinations of azoles could slow the evolution of resistance. This work was initiated to assess the effects of dose, mixtures and alternations of two azoles on selection for isolates with reduced sensitivity and on disease control. Naturally infected field trials were carried out at six sites across Ireland and the sensitivity of Z. tritici isolates monitored pre- and post-treatment. The azoles epoxiconazole and metconazole were applied as solo products, in alternation with each other and as a pre-formulated mixture. Full and half label doses were tested. The two azoles were partially cross-resistant, with a common azole resistance principal component accounting for 75% of the variation between isolates. Selection for isolates with reduced azole sensitivity was correlated with disease control. Decreased doses were related to decreases in sensitivity but the effect was barely significant (P = 0.1) and control was reduced. Single applications of an active ingredient (a.i.) caused smaller decreases in sensitivity than double applications. Shifts in sensitivity to the a.i. applied to a plot were greater than to the a.i. not applied, and the decrease in sensitivity was greater to the a.i. applied at the second timing. These results confirm the need to mix a.i.s with different modes of action.

The degradation behavior of alumina (10–20 wt%) carbon refractories was investigated during high temperature (1 550 °C) contact with a ternary casting mould meniscus slag containing 50% MnO, 25% SiO2, and 25% Al2O3 and a binary slag containing 40% MnO and 60% SiO2. Using the sessile drop approach, the transient progress of corrosion reactions was investigated as a function of time and refractory composition. An in-depth characterization and analysis of reacted assemblies was carried out using optical and scanning electron microscopy (SEM). Optical micrographs showed a significant penetration of both slags within the refractory substrate, with very little slag remaining behind after 15 min of contact. The depth of penetration of ternary slag was found to increase with carbon concentration in the refractory. An all-round corrosion was observed with extensive refractory degradation over a period of time. Corrosion was determined to a great extent by dissolution reactions in the interfacial region; alumina dissolution from the refractory resulted in the formation of needle-like corundum crystallites which transformed to a cohesive network of faceted corundum crystals on extended contact. A number of reaction products containing Mn and Si were also observed.

We report an investigation on the corrosion behavior of ZrO2–graphite insert in submerged entry nozzles (SEN) during its high temperature interaction with the mould flux focused specifically on the role of glaze coating. A detailed metallographic examination of the representative samples collected at different stages of its usage was carried out to examine the transient progress of corrosion. The interaction between the glaze material and the base refractory at the typical preheating temperature of SEN initiated the degradation of the partially stabilized ZrO2 grains due to the formation of reaction products. Clear evidence is presented to show that the reaction product and the original layer of glaze coating survived after 90 min of casting. Early stages of corrosion involved the progressive congruent dissolution of reaction products and the residual glaze phase into the mould flux. Due to the absence of the glaze layer in the later stages of operation (480 min), corrosion was caused by the fragmentation of the aggregate phase and structural damage. This work highlights the importance of compositional control and coating thickness of the glaze material on the ZrO2–graphite refractory insert.

The degradation behavior of Zirconia – 20% carbon refractory was investigated during high temperature (1550 °C) contact with a casting mould meniscus slag containing 50% MnO, 25% SiO2, and 25% Al2O3. Using the sessile drop approach, the transient progress of corrosion reactions was investigated as a function of time; in-depth characterization and analysis of reacted assemblies was carried out using optical and scanning electron microscopy. Optical micrographs showed a significant penetration of slag within the refractory substrate, with very little slag remaining behind after 15 min of contact. In situ carbothermic reduction of zirconia and the presence of reducible oxides in the slag significantly depleted carbon from the substrate further aiding the penetration of slag. Interaction between slag and zirconia resulted in the depletion of phase-stabilizing Y2O3 from zirconia granules resulting in their fragmentation and subsequent diffusion in slag rich regions. An aggressive all-round corrosion was observed with extensive refractory degradation over a period of time; a number of reaction products such as Mn5Si3 were also observed. These experimental investigations were supplemented with thermodynamic investigations using FactSage.

Food ingredient fraud and economically motivated adulteration are emerging risks, but a comprehensive compilation of information about known problematic ingredients and detection methods does not currently exist. The objectives of this research were to collect such information from publicly available articles in scholarly journals and general media, organize into a database, and review and analyze the data to identify trends. The results summarized are a database that will be published in the US Pharmacopeial Convention's Food Chemicals Codex, 8th edition, and includes 1305 records, including 1000 records with analytical methods collected from 677 references. Olive oil, milk, honey, and saffron were the most common targets for adulteration reported in scholarly journals, and potentially harmful issues identified include spices diluted with lead chromate and lead tetraoxide, substitution of Chinese star anise with toxic Japanese star anise, and melamine adulteration of high protein content foods. High-performance liquid chromatography and infrared spectroscopy were the most common analytical detection procedures, and chemometrics data analysis was used in a large number of reports. Future expansion of this database will include additional publically available articles published before 1980 and in other languages, as well as data outside the public domain. The authors recommend in-depth analyses of individual incidents. Practical Application: This report describes the development and application of a database of food ingredient fraud issues from publicly available references. The database provides baseline information and data useful to governments, agencies, and individual companies assessing the risks of specific products produced in specific regions as well as products distributed and sold in other regions. In addition, the report describes current analytical technologies for detecting food fraud and identifies trends and developments.

This paper investigates and reviews literature regarding a range of topics important to the research question – the themes apply across all the topics. The topics include label and package warnings, including tamper-evident features, to review their effect on the consumer behaviour of changing usage or purchase decisions. This information was then applied to gain insight into anticounterfeit product/package efforts. Based on this research, it appears that there is value for brand marketers to enhance their anticounterfeit efforts and consumer confidence by utilizing warning labels and information labels on their labels or packages. Currently, consumer perception of a domestic counterfeit product threat (promoted as genuine products), even for pharmaceuticals by healthcare professionals, although increasing has still been very low. Generally, the consumers believe and expect that the product purchased from retailers is safe and genuine. The study reviewed many key warning and label communication areas: consumer behaviour review, technical specifications, anticounterfeit, tamper evidence/tamper resistance, over-the-counter drugs, alcohol, cigarette, nutrition food and nutrition supplements. To complete the insight on communicating with the consumer, a review of label legibility was included. Before brand marketers consider adding anticounterfeit warning labels, extensive consumer behaviour research should be conducted in areas such as fear appeals and involuntary risk outrage. Copyright © 2011 John Wiley & Sons, Ltd.

Lodging resistance ratings for winter wheat cultivars are frequently based upon observations of lodging. This is an unreliable method because of the frequent occurrence of years without significant lodging events. It also does not distinguish between stem and root lodging resistance. This paper describes the development and testing of instrumentation and procedures for two field-based methods to rapidly assess stem and root lodging resistance. Both methods used a specifically designed instrument for measuring the resistance of shoots against rotational displacement. Stem lodging resistance was assessed when the soil was dry and strong, whereas resistance to root lodging was assessed after the soil had been weakened by irrigation. Tests were carried out on 14 winter wheat cultivars grown at two sites in the UK during 2002. Both methods were able to detect statistically significant differences between the cultivars for their resistance to stem and root lodging. A comparison of these results with observations of lodging in the field showed that the methods accounted for about 60 and 50 % of the stem and root lodging respectively.

Potato tuber necrotic ringspot disease (PTNRD) as described by Kus et al., (1992) is found worldwide but has not previously been identified in Ireland. In recent years necrotic symptoms, veinal necrosis, spots, mottling, mosaics and…