Can crop disease control cope with climate change?

Crop yields need to increase by at least 70% over the next 35 years in order to meet the global demands for food due to the increasing population and changing dietary preferences towards meat and dairy products in developing nations. Climate change threatens food security because pests and diseases that limit crop productivity are all sensitive to climate change and especially to more frequent extreme weather events. A more variable climate will mean greater uncertainty for crop yields because crop development stages, e.g. when reproductive organs such as flowers and seeds are produced, are especially vulnerable to short periods of extreme temperature or drought. For instance, Europe experienced an extreme climate event during the summer of 2003 when temperatures were ca. 6°C higher and rainfall was ca. 300 mm less than the long-term mean values. One impact of this summer was a record crop yield decrease of ca. 36% below average yield in Italy for maizePeer reviewedFinal Accepted Versio

Fluctuations in Number of Cercospora beticola Conidia in Relationship to Environment and Disease Severity in Sugar Beet

All content of Phytopathology is open access without restriction 12 months after publicationCercospora leaf spot, caused by Cercospora beticola, is the most damaging foliar disease of sugar beet in Minnesota (MN) and North Dakota (ND). Research was conducted to characterize the temporal progression of aerial concentration of C. beticola conidia in association with the environment and disease severity in sugar beet. In 2003 and 2004, volumetric spore traps were placed within inoculated sugar beet plots to determine daily dispersal of conidia at Breckenridge, MN, and St. Thomas, ND. Plots were rated weekly for disease severity. At both locations, conidia were first collected in early July 2003 and late June in 2004. Peaks of conidia per cubic meter of air were observed with maxima in late August 2003 and in early September 2004 at both locations. Peaks of airborne conidium concentration were significantly correlated with the average temperature of daily hours when relative humidity was greater than 87%. Weekly mean hourly conidia per cubic meter of air was significantly (P <0.01) associated with disease severity during both years and across locations. This study showed that C. beticola conidial numbers may be used to estimate potential disease severity that, with further research, could be incorporated in a disease forecasting model to rationalize Cercospora leaf spot management.Peer reviewe

Grassland futures in Great Britain – Productivity assessment and scenarios for land use change opportunities

This is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).To optimise trade-offs provided by future changes in grassland use intensity, spatially and temporally explicit estimates of respective grassland productivities are required at the systems level. Here, we benchmark the potential national availability of grassland biomass, identify optimal strategies for its management, and investigate the relative importance of intensification over reversion (prioritising productivity versus environmental ecosystem services). Process-conservative meta-models for different grasslands were used to calculate the baseline dry matter yields (DMY; 1961–1990) at 1 km2 resolution for the whole UK. The effects of climate change, rising atmospheric [CO2] and technological progress on baseline DMYs were used to estimate future grassland productivities (up to 2050) for low and medium CO2 emission scenarios of UKCP09. UK benchmark productivities of 12.5, 8.7 and 2.8 t/ha on temporary, permanent and rough-grazing grassland, respectively, accounted for productivity gains by 2010. By 2050, productivities under medium emission scenario are predicted to increase to 15.5 and 9.8 t/ha on temporary and permanent grassland, respectively, but not on rough grassland. Based on surveyed grassland distributions for Great Britain in 2010 the annual availability of grassland biomass is likely to rise from 64 to 72 million tonnes by 2050. Assuming optimal N application could close existing productivity gaps of ca. 40% a range of management options could deliver additional 21 ∗ 106 tonnes of biomass available for bioenergy. Scenarios of changes in grassland use intensity demonstrated considerable scope for maintaining or further increasing grassland production and sparing some grassland for the provision of environmental ecosystem services.Peer reviewedFinal Published versio

Evaluating Responses of Sugar Beet Cultivars to Fusarium Species in Greenhouse and Field Conditions

Fusarium yellows of sugar beet (Beta vulgaris L.) is becoming an important disease in Minnesota and North Dakota in the United States. One of the best ways to manage Fusarium yellows is to develop and use resistant cultivars. Responses of eight sugar beet cultivars to three Fusarium species were determined in the greenhouse and compared to the responses of the same eight cultivars grown in a field already infected by Fusarium yellows. There were significant and appreciable relationships between greenhouse and field studies for responses of eight sugar beet cultivars on Fusarium yellows. The estimated correlation coefficient for area under disease progress curve (AUDPC) between observations in fields and those in greenhouses was 0.987 (p<0.01). The mean AUDPC were significantly different among cultivars (p<0.01) in the greenhouse and in the field studies. Of the cultivars, Van der Have 46177 was the most susceptible, but Crystal R434 the most resistant. Crystal 820, Van der Have 66561, and Beta 4797R were resistant, and Beta 4818R, Seedex Magnum, and Hilleshog 2463Rz were moderately resistant. There was a strong negative relationship between the AUDPC and recoverable sucrose yield in the field experiments and the estimated coefficient of determination was 0.939 (p<0.01). It was concluded that greenhouse screening can act as a useful and reliable means to evaluate and select beet germplasms and/or accessions for resistance to Fusarium yellows.Peer reviewe

Effectiveness of Rlm7 resistance against Leptosphaeria maculans (phoma stem canker) in UK winter oilseed rape cultivars

© 2018 The Authors. Plant Pathology published by John Wiley & Sons Ltd on behalf of British Society for Plant Pathology. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.The Rlm7 gene in Brassica napus is an important source of resistance for control of phoma stem canker on oilseed rape caused by the fungus Leptosphaeria maculans. This study shows the first report of L. maculans isolates virulent against Rlm7 in the UK. Leptosphaeria maculans isolates virulent against Rlm7 represented 3% of the pathogen population when cultivars with the Rlm7 gene represented 5% of the UK oilseed rape area in 2012/13. However, the Rlm7 gene has been widely used since then, representing >15% of the UK oilseed rape area in 2015/16. Winter oilseed rape field experiments included cultivars with the Rlm7 gene, with the Rlm4 gene or without Rlm genes and took place at five sites in the UK over four cropping seasons. An increase in phoma leaf spotting severity on Rlm7 cultivars in successive seasons was observed. Major resistance genes played a role in preventing severe phoma leaf spotting at the beginning of the cropping season and, in addition, quantitative resistance (QR) in the cultivars examined made an important contribution to control of phoma stem canker development at the end of the cropping season. Deployment of the Rlm7 resistance gene against L. maculans in cultivars with QR in combination with sustainable disease management practices will prolong the use of this gene for effective control of phoma stem canker epidemics.Peer reviewe

Opportunities for weed manipulation using GMHT row crops

The herbicides and cultivation systems available in most non-GM crops allow farmers little flexibility as to when they control weeds. However, glyphosate and glufosinate-ammonium, as used in GM herbicide tolerant crops, offer the opportunity to control large weeds and weed control can be timed according to the agronomic and environmental aims of the user. This paper will use sugar beet as a model crop and report results where different approaches to weed control have been used and discuss their relevance in the wider agricultural and environmental contextNon peer reviewe

Control of crop diseases through Integrated Crop Management to deliver climate-smart farming systems for low and high input crop production

© 2021 The Authors. Plant Pathology published by John Wiley & Sons Ltd on behalf of British Society for Plant Pathology. This is an open access article under the terms of the Creative Commons Attribution License. https://creativecommons.org/licenses/by/4.0/Crop diseases affect crop yield and quality and cause significant losses of total food production worldwide. With the ever‐increasing world population and decreasing land and water resources, there is a need not only to produce more food but also to reduce agricultural greenhouse gas (GHG) emissions to mitigate climate change and avoid land use change and biodiversity loss. Thus, alternative climate‐smart farming systems need to adapt to produce more food per hectare in a more sustainable way than conventional high‐input farming systems. In addition to breeding new high‐yielding cultivars adapted to future climates, there is a need to deploy Integrated Crop Management (ICM) strategies, relying less on synthetic inputs for fertilization and crop protection and less on fossil fuel‐powered machinery to decrease yield losses due to pest and pathogens and guarantee food security. In this review, we compare some low‐input farming systems to conventional agricultural systems with a focus on ICM solutions being developed to reduce synthetic inputs; these include crop genetic resistance to pathogens, intercropping, canopy architecture manipulation, and crop rotation. These techniques have potential to decrease crop disease frequency and severity by decreasing amounts and dispersal of pathogen inoculum and by producing microclimates that are less favourable for pathogen development, while decreasing GHG emissions and improving environmental sustainability. More research is needed to determine the best deployment of these ICM strategies in various cropping systems to maximize yield, crop protection, and other ecosystem services to address trade‐offs between climate change and food security.Peer reviewedFinal Published versio

Trends of pesticide residues in foods imported to the United Kingdom from 2000 to 2020

© 2021 Elsevier Ltd. All rights reserved. This is the accepted manuscript version of an article which has been published in final form at https://doi.org/10.1016/j.foodcont.2021.108616A total of 33,911 samples with determined pesticide residues were collated and analysed in the UK monitoring programme to determine trends in pesticide residue levels in imported foods during the period of 2000–2020. 17,027 of those samples (50.2%) contained detectable residues while 1,126 (3.3%) exceeded maximum residue levels (MRLs). An increased trend and a significant shift before and after 2010 in imported foods containing both detectable residues and exceeding MRLs were found. The main factors responsible for these changes were due to constant amendments in regulations and legal frameworks. With adoption of Regulation EC396/2005, there have been major changes that have affected the operations of the UK food monitoring programme including sampling methods, analysis methods, new MRLs, types of foods, and the accreditation system. The proportion of imported foods with residues and the amounts of residues in imported foods varied from country to country. Foods imported from non-European countries had more non-compliant rates than foods imported from EU. Levels of pesticide residues also varied between processed foods and unprocessed raw agricultural products and between plant-based and animal foods. Fruits and vegetables and cereals had higher occurrences of quantified residues as well as higher MRLs violation rates compared to animal products.Peer reviewe

Disease management in oilseed rape: insights into the Brassica napus-Pyrenopeziza brassicae pathosystem

Final Published versio

Combining Penthiopyrad with Azoxystrobin is an Effective Alternative to Control Seedling Damping-off Caused by Rhizoctonia solani on Sugar Beet

The soil-borne fungus Rhizoctonia solani causes damping-off on sugar beet seedlings. Growers rely on fungicides to protect sugar beet in fields affected by R. solani. Quinone outside inhibitor (QoI) fungicides, such as azoxystrobin, have been applied as in-furrow and foliar sprays to manage R. solani, but repeated use of QoI fungicides pose risks in fungicide resistance. Penthiopyrad is a novel fungicide with the succinate dehydrogenase inhibitor (SDHI) mode of action. The objectives of this study were to compare the efficacy of penthiopyrad used as a sole seed treatment versus azoxystrobin as an in-furrow or a post-planting application for controlling R. solani; to determine if a penthiopyrad seed treatment combined with azoxystrobin as a post-planting application can improve control of R. solani over sole penthiopyrad seed treatment, azoxystrobin in-furrow or post-planting spray application. Seedling survival rate and area under disease progress curve (AUDPC) for seedling loss rate were used to measure the efficacy of each treatment. A sole penthiopyrad seed treatment at 14 g a.i. kg-1 of seeds, and penthiopyrad seed treatments at 7 and 14 g a.i. kg-1 of seeds combined with one azoxystrobin in-furrow application 14 days after planting resulted in similar seedling survival rate and AUDPC as achieved with the standard azoxystrobin in-furrow application. However, post-planting foliar spray of azoxystrobin alone failed to control seedling damping-off. Our research suggests that penthiopyrad can be used as a seed treatment to provide early protection to vulnerable seedlings while azoxystrobin can be used as a post-planting application to protect the ensuing adult plantsPeer reviewedFinal Accepted Versio