European Field Trials Research Articles

Agronomic performance of novel, nitrogen-rich biobased fertilizers across European field trial sites

Context or problemSubstituting mineral fertilizers with novel biobased fertilizers (BBFs) produced from various organic waste and side streams could contribute to a reduction in the environmental and climate impacts of fertilizer production and use and the recycling of otherwise potentially wasted nutrients. For the substitution to be beneficial for farmers, the environment, and food security, the BBFs need to be effective, reliable and safe. However, the agronomic performance of novel, nitrogen (N) rich BBFs has not yet been well studied. Objectives or research questionThe main objective of this study was to determine the agronomic efficiency of N in a relevant range of commercially available BBFs. We hypothesised that they can function as effective substitutes for mineral N fertilizers, independent of the agricultural and geographic settings. MethodsField trials (fully randomized block design) were conducted at four field sites across Europe covering different climates, soil types, and crop sequences. In total 18 BBFs were tested, 7 of which were common BBFs tested at all sites, while the other 11 (2–3 per site) were local BBFs at individual sites. The design included 4–5 increasing levels of mineral N reference. Trials with BBF application were conducted over 2 years, and the agronomic performance (crop yield and N offtake) was determined to estimate 1st year mineral N fertilizer replacement value (NFRV) in both years, while residual NFRV was estimated only in the 2nd year. ResultsThe BBFs showed an average N fertilizer replacement value (NFRV) of 70 % across sites and years, with variations in the agronomic performance between the trial sites and years. Compared with the mineral N fertilizer reference applied at the same total N level, no consistent ranking of BBF and no significant differences in yields were found. The BBFs tended to have a higher NFRV when incorporated compared to surface application. Of the 18 BBFs tested, 8 had a NFRV above 75 %, 6 were in the range 60–75 % and 4 were in the low range of 10–60 %. The residual effect of BBFs in the year after application was not significantly higher for any of the BBFs than that of the mineral N fertilizer. ConclusionsGenerally, the BBFs performed similar to the mineral reference applied at the same total N level. The performance of BBFs was not significantly affected by climate or soil type. The BBFs appeared to have higher agronomic performance when incorporated into the soil compared to surface application. The second year residual effect of BBF was not significantly higher than that of the mineral reference fertilizer. Implications or significanceIn general, most of the investigated BBFs can be considered reasonably effective substitutes for mineral N fertilizers. The results suggest that soil incorporation of BBFs will result in better agronomic performance than surface application.

Limited influence of air temperature and precipitation on six-year survival and growth of non-native tree species in a Central European multi-site field trial

The biggest challenge for forest management in the near future will be the silvicultural adaptation of forests on sites where climate change will increase the risk for drought induced tree mortality and for a decrease of the growth performance. One management option is the diversification by promoting climate change adapted non-native tree species. Currently, we have in depth experience with only a few non-native tree species in Central Europe. Other tree species that may complement the species pool in Central Europe need to be carefully selected by a range of criteria. Before establishing larger silvicultural experiments at stand-level, the suitability of species to grow well with a low risk of failure under expected future climatic conditions as well as a good performance already today should be tested, amongst other aspects. We present results of a multi-site common garden experiment where growth and survival of five non-native tree species (Abies bornmuelleriana, Cedrus libani, Fagus orientalis, Tilia tomentosa, and Tsuga heterophylla) and one climate adapted local native species per site are tested in five field trials in Austria, Germany and Switzerland along a temperature (7.9–10.4 °C mean annual Temperature) and precipitation (490–1147 mm annual precipitation) gradient. Each species was replicated on three plots per site using a block-wise design. Lower survival and growth of the non-native species as the native reference on most sites indicate that the studied non-native species are today not as well adapted to current climatic conditions as native species. However, the performance of the non-native species was sufficiently high to justify further trials. Survival and growth rates were mostly equally high on the two sites at the opposing ends of the temperature and humidity gradient and lower on all other sites. Height growth and survival were only marginally affected by the strong summer drought in 2018 in all except one site, presumably due to the low water storage capacity of the sandy soils on this site. This indicates that the tested non-native tree species grow well in the wide range of climatically changing weather conditions from our transnational study sites across Central Europe. So far, the tested tree species did not reach their climatic growth limitation. However, edaphic site conditions may have influenced the performance of the tested non-native species as well and must be considered when discussing the suitability of these tree species.

Recovery efficiency of the damaged porous asphalt mixture with emulsion-based surface treatment: Material optimization and performance verification

• Recovery efficiency of ST emulsions on damaged PA was evaluated by Cantabro abrasion test. • Both application rate and solid content of the ST emulsions can affect the performance recovery of PA. • Application of ST emulsions has a manageable side-effect on the functional performance of PA. Porous asphalt (PA) road surfaces usually have short service lives due to quick raveling. Recent field trials in Europe have shown that spraying surface-treatment (ST) asphalt emulsion is a potential method to address this problem. However, the recovery efficiency of ST emulsion in PA mixture is currently unknown, limiting the wide application of this preventive maintenance technique in practice. Therefore, this study aims to investigate the key factors affecting the recovery efficiency of ST emulsion when it is applied to damaged PA. The Cantabro abrasion tests were first conducted on damaged PA specimens with and without ST emulsions to evaluate the recovery performances of different ST scenarios. The functional properties, including noise-absorption, permeability, and skid-resistance, under the optimized ST application scenario were then characterized for verification purposes. The testing results showed that the abrasion loss of the damaged PA mixture under ST emulsion was significantly reduced after 3 days of curing. Both the application rate and solid content of ST emulsion are critical factors affecting the raveling resistance recovery of the damaged PA mixture. However, the addition of the bio-based or petrol-based rejuvenator has a negligible impact on the performance recovery of the damaged PA mixtures after 14 days of curing, indicating the diffusion of the ST emulsion (if any) may require a long time in this scenario. Besides, the application of the ST emulsion may have a slight side-effect on the functional performance of PA in the short term, necessitating functional performance verification for the ST emulsion design.

The Reaction of Cellulolytic and Potentially Cellulolytic Spore-Forming Bacteria to Various Types of Crop Management and Farmyard Manure Fertilization in Bulk Soil

The ecology of cellulolytic bacteria in bulk soil is still relatively unknown. There is still only a handful of papers on the abundance and diversity of this group of bacteria. Our study aimed to determine the impact of various crop management systems and farmyard manure (FYM) fertilization on the abundance of cellulolytic and potentially cellulolytic spore-forming bacteria (SCB). The study site was a nearly 100-year-old fertilization experiment, one of the oldest still active field trials in Europe. The highest contents of total carbon (TC) and total nitrogen (TN) were recorded in both five-year rotations. The abundances of SCB and potential SCB were evaluated using classical microbiological methods, the most probable number (MPN), and 16S rRNA Illumina MiSeq sequencing. The highest MPN of SCB was recorded in soil with arbitrary rotation without legumes (ARP) fertilized with FYM (382 colony-forming units (CFU) mL−1). As a result of the bioinformatic analysis, the highest values of the Shannon–Wiener index and the largest number of operational taxonomic units (OTUs) were found in ARP-FYM, while the lowest in ARP treatment without FYM fertilization. In all treatments, those dominant at the order level were: Brevibacillales (13.1–43.4%), Paenibacillales (5.3–36.9%), Bacillales (4.0–0.9%). Brevibacillaceae (13.1–43.4%), Paenibacillaceae (8.2–36.9%), and Clostridiaceae (5.4–11.9%) dominated at the family level in all tested samples. Aneurinibacillaceae and Hungateiclostridiaceae families increased their overall share in FYM fertilization treatments. The results of our research show that the impact of crop management types on SCB was negligible while the actual factor shaping SCB community was the use of FYM fertilization.

Dynamics of soil phosphorus measured by ammonium lactate extraction as a function of the soil phosphorus balance and soil properties

A sustainable supply of phosphorus (P) to agricultural soils should maintain soil fertility without jeopardizing the environment. This study analyzed the change in the soil P as a function of the net soil P mass balance, i.e. the input minus removal by the harvested crop. The P available for crops was estimated by the P extracted by ammonium lactate at pH 3.75 (P-AL). First, laboratory and pot-trial data showed that the net change in soil P-AL was only 68% of the change in total soil P, either when P had been added to soil or when P had been mined by plants for 1–2 years, indicating removal to or release from the non-extractable pool depending on the balance. Secondly, data were collated from 33 field trials in Europe with a wide range of cumulative soil P balances (−1200 to +2500 kg P ha−1) in time spans ranging from 3 to 51 years. The average change in P-AL across the negative and positive balance was only 27% (95% confidence interval 25–30%) of the net balance. The change in P-AL was larger as the net balance increased and as the initial P-AL decreased. The slope of the change versus the balance was smaller as time increased and initial P-AL decreased. The other soil characteristics did not affect these changes, and the model developed was not different for negative or positive P balances. Our results suggest that a steady state P-AL concentration at optimal P supply for crops is obtained at a net P balance of about 1–10 kg P ha−1. The P mass balance of a 51 year-old trial showed that the aqua regia soluble P of the 0–90 cm layer accounted for only 64% of the net P balances at the surface. This still incomplete P balance could be related to upward P transport by plant uptake from > 90 cm soil layers, lateral P movement in the field, and changes in the soil P fraction that could not be extracted with aqua regia. This study quantified the long-term dynamics of P-AL, which is useful for agronomic and environmental purposes and policy, and pointed out the importance of non-extractable P and vertical P movement.

Food/Feed and Environmental Risk Assessment of Insect-resistant and Herbicide-tolerant Genetically Modified Maize 59122 x 1507 x NK603 for Food and Feed Uses, Import and Processing under Regulation (EC) No 1829/2003 (EFSA/GMO/UK/2005/21)

Food/Feed and Environmental Risk Assessment of Insect-resistant and Herbicide-tolerant Genetically Modified Maize 59122 x 1507 x NK603 for Food and Feed Uses, Import and Processing under Regulation (EC) No 1829/2003 (EFSA/GMO/UK/2005/21)

Maize root‐derived C in soil and the role of physical protection on its relative stability over shoot‐derived C

Evidence is accumulating that belowground crop residues contribute more efficiently to the build‐up and maintenance of native soil organic carbon (SOC) than aboveground plant parts. We corroborated previous testing of the hypothesis that root‐C would preferentially accumulate in soil microaggregates, where it is physically protected against microbially mediated decomposition. In three European field trials with C3 to C4 crop transitions, we compared the content of maize‐C (Zea mays L.) in soil from rotations with grain maize (MG) or silage maize (MS) (i.e. with incorporation of roots and shoots or roots only). After decades of maize cultivation, SOC content did not differ within three out of four MG–MS pairs, although obviously larger amounts of shoot biomass were added to soil in the case of MG. We found that relative contribution of roots was on average 3.5 times more than shoots to the build‐up of SOC per equivalent mass of residue C added to soils. Preferential occlusion of root‐C as silt‐sized intra‐microaggregate particulate organic matter (iPOM) was not observed. There were much larger effects from shoot incorporation on maize‐C in the >53‐μm fraction and free silt and clay. Storage of root‐C as sand‐sized iPOM was not quantified here, but first estimates suggested that physical entrapment at this level could only partly explain the longevity of root‐C in soil. We reconfirm the relative stability of root‐C in soil, but do not conclude that this stems from preferential physical entrapment over shoot‐C. Future work should investigate the cause of preferential root‐C association with the clay‐sized fraction and if this occurs before or after microbial processing.Highlights The hypothesized preferential physical stabilization of root‐C was assessed. Aboveground biomass had a minor effect on SOC storage in European long‐term trials. Contribution of maize root‐C to maintenance of SOC was three‐fold that of shoot‐C inputs. There was no preferential occlusion of root‐C in silt‐sized microaggregates.

Enhancing Soil Organic Matter as a Route to the Ecological Intensification of European Arable Systems

Soil organic matter (SOM) is declining in most agricultural ecosystems, impacting multiple ecosystem services including erosion and flood prevention, climate and greenhouse gas regulation as well as other services that underpin crop production, such as nutrient cycling and pest control. Ecological intensification aims to enhance crop productivity by including regulating and supporting ecosystem service management into agricultural practices. We investigate the potential for increased SOM to support the ecological intensification of arable systems by reducing the need for nitrogen fertiliser application and pest control. Using a large-scale European field trial implemented across 84 fields in 5 countries, we tested whether increased SOM (using soil organic carbon as a proxy) helps recover yield in the absence of conventional nitrogen fertiliser and whether this also supports crops less favourable to key aphid pests. Greater SOM increased yield by 10%, but did not offset nitrogen fertiliser application entirely, which improved yield by 30%. Crop pest responses depended on species: Metopolophium dirhodum were more abundant in fertilised plots with high crop biomass, and although population growth rates of Sitobion avenae were enhanced by nitrogen fertiliser application in a cage trial, field populations were not affected. We conclude that under increased SOM and reduced fertiliser application, pest pressure can be reduced, while partially compensating for yield deficits linked to fertiliser reduction. If the benefits of reduced fertiliser application and increased SOM are considered in a wider environmental context, then a yield cost may become acceptable. Maintaining or increasing SOM is critical for achieving ecological intensification of European cereal production.

Biological characterization of fenpicoxamid, a new fungicide with utility in cereals and other crops.

BACKGROUNDThe development of novel highly efficacious fungicides that lack cross‐resistance is extremely desirable. Fenpicoxamid (Inatreq™ active) possesses these characteristics and is a member of a novel picolinamide class of fungicides derived from the antifungal natural product UK‐2A.RESULTSFenpicoxamid strongly inhibited in vitro growth of several ascomycete fungi, including Zymoseptoria tritici (EC50, 0.051 mg L−1). Fenpicoxamid is converted by Z. tritici to UK‐2A, a 15‐fold stronger inhibitor of Z. tritici growth (EC50, 0.0033 mg L−1). Strong fungicidal activity of fenpicoxamid against driver cereal diseases was confirmed in greenhouse tests, where activity on Z. tritici and Puccinia triticina matched that of fluxapyroxad. Due to its novel target site (Qi site of the respiratory cyt bc1 complex) for the cereals market, fenpicoxamid is not cross‐resistant to Z. tritici isolates resistant to strobilurin and/or azole fungicides. Across multiple European field trials Z. tritici was strongly controlled (mean, 82%) by 100 g as ha−1 applications of fenpicoxamid, which demonstrated excellent residual activity.CONCLUSIONSThe novel chemistry and biochemical target site of fenpicoxamid as well as its lack of cross‐resistance and strong efficacy against Z. tritici and other pathogens highlight the importance of fenpicoxamid as a new tool for controlling plant pathogenic fungi. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Assessing phytotoxicity of trace element-contaminated soils phytomanaged with gentle remediation options at ten European field trials

Gentle remediation options (GRO), i.e. in situ stabilisation, (aided) phytoextraction and (aided) phytostabilisation, were implemented at ten European sites contaminated with trace elements (TE) from various anthropogenic sources: mining, atmospheric fallout, landfill leachates, wood preservatives, dredged-sediments, and dumped wastes. To assess the performance of the GRO options, topsoil was collected from each field trial, potted, and cultivated with lettuce (Lactuca sativa L.) for 48days. Shoot dry weight (DW) yield, photosynthesis efficiency and major element and TE concentrations in the soil pore water and lettuce shoots were measured.GRO implementation had a limited effect on TE concentrations in the soil pore water, although use of multivariate Co-inertia Analysis revealed a clear amelioration effect in phytomanaged soils. Phytomanagement increased shoot DW yield at all industrial and mine sites, whereas in agricultural soils improvements were produced in one out of five sites. Photosynthesis efficiency was less sensitive than changes in shoot biomass and did not discriminate changes in soil conditions.Based on lettuce shoot DW yield, compost amendment followed by phytoextraction yielded better results than phytostabilisation; moreover shoot ionome data proved that, depending on initial soil conditions, recurrent compost application may be required to maintain crop production with common shoot nutrient concentrations.

Progress in upscaling Miscanthus biomass production for the European bio‐economy with seed‐based hybrids

AbstractField trials in Europe with Miscanthus over the past 25 years have demonstrated that interspecies hybrids such as M. × giganteus (M × g) combine both high yield potentials and low inputs in a wide range of soils and climates. Miscanthus hybrids are expected to play a major role in the provision of perennial lignocellulosic biomass across much of Europe as part of a lower carbon economy. However, even with favourable policies in some European countries, uptake has been slow. M × g, as a sterile clone, can only be propagated vegetatively, which leads to high establishment costs and low multiplication rates. Consequently, a decade ago, a strategic decision to develop rapidly multiplied seeded hybrids was taken. To make progress on this goal, we have (1) harnessed the genetic diversity in Miscanthus by crossing and progeny testing thousands of parental combinations to select several candidate seed‐based hybrids adapted to European environments, (2) established field scale seed production methods with annual multiplication factors >1500×, (3) developed the agronomy for establishing large stands from seed sown plug plants to reduce establishment times by a year compared to M × g, (4) trialled a range of harvest techniques to improve compositional quality and logistics on a large scale, (5) performed spatial analyses of yield potential and land availability to identify regional opportunities across Europe and doubled the area within the bio‐climatic envelope, (6) considered on‐farm economic, practical and environmental benefits that can be attractive to growers. The technical barriers to adoption have now been overcome sufficiently such that Miscanthus is ready to use as a low‐carbon feedstock in the European bio‐economy.

The Future of Field Trials in Europe: Establishing a Network Beyond Boundaries.

We propose the establishment of a European Consortium for Open Field Experimentation (ECOFE) that will allow easy access of European plant and soil scientists to experimental field stations that cover all major climatological regions. Coordination and quality control of data extraction and management systems will greatly impact on our ability to cope with grand challenges such as climate change and food security.

Long-term effects of best management practices on crop yield and nitrogen surplus

Inherent in the concept of good agricultural practice (BMP) is that it improves resource use efficiency, mitigates environmental impact or increases farm profitability. However, it is usually impossible to achieve all the objectives, and trade-offs need to be accepted, such as a reduction in productivity together with a reduction in costs or an increase of soil organic matter. A European FP7 project, Catch-C (http://www.catch-c.eu) analyses the effects that different management practices have on productivity, mitigation of climate change and chemical, physical and biological soil fertility, based on simple indicators. Such indicators were collected from international literature, national scientific or technical journals, or grey literature that dealt with long-term field trials in Europe. We collected and analysed data from more than 350 experiments. This paper presents the overall results of the effects of a series of BMP have on crop productivity, soil nitrogen (N) uptake, N use efficiency end N balance. Important interactions with soil and climate types, crop and duration of the experiment were noticed for most BMPs. Rotations, also including double cropping, were among practices with more positive effects of productivity and N indicators. A slight reduction of yield counteracted benefits to soil quality and to climate change mitigation of minimum and no tillage, and of organic fertilisers.

Dent and Flint maize diversity panels reveal important genetic potential for increasing biomass production.

Genetic and phenotypic analysis of two complementary maize panels revealed an important variation for biomass yield. Flowering and biomass QTL were discovered by association mapping in both panels. The high whole plant biomass productivity of maize makes it a potential source of energy in animal feeding and biofuel production. The variability and the genetic determinism of traits related to biomass are poorly known. We analyzed two highly diverse panels of Dent and Flint lines representing complementary heterotic groups for Northern Europe. They were genotyped with the 50 k SNP-array and phenotyped as hybrids (crossed to a tester of the complementary pool) in a western European field trial network for traits related to flowering time, plant height, and biomass. The molecular information revealed to be a powerful tool for discovering different levels of structure and relatedness in both panels. This study revealed important variation and potential genetic progress for biomass production, even at constant precocity. Association mapping was run by combining genotypes and phenotypes in a mixed model with a random polygenic effect. This permitted the detection of significant associations, confirming height and flowering time quantitative trait loci (QTL) found in literature. Biomass yield QTL were detected in both panels but were unstable across the environments. Alternative kinship estimator only based on markers unlinked to the tested SNP increased the number of significant associations by around 40% with a satisfying control of the false positive rate. This study gave insights into the variability and the genetic architectures of biomass-related traits in Flint and Dent lines and suggests important potential of these two pools for breeding high biomass yielding hybrid varieties.

Miscanthus, a host for larvae of a European population of Diabrotica v. virgifera

The EU policies for decreasing reliance on fossil fuels and reducing greenhouse gas emissions present challenging targets for bioenergy production. Field trials in Europe of Miscanthus×giganteus (Poales: Poaceae) over the past 20 years have shown that this plant is suitable for the production of biomass but the economic models promoting its use for this purpose often assume that controlling its pests will cost little or nothing. Laboratory experiments were conducted to determine whether this plant is suitable for the development of larvae of the western corn rootworm (WCR), Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae), which is an important pest of maize. Larvae of WCR, originating from a Central and South Eastern European population, can develop on Miscanthus.

Workshop COST E52 “Evaluation of beech genetic resources for sustainable forestry”

Abstract: The main objective of the COST Action E52 “Evaluation of Beech Genetic Resources for Sustainable Forestry” is to make predictions of the future distribution range of beech forest ecosystems under the assumption of certain scenarios of climate change, based on the analysis of the reaction pattern of European beech populations of defined origin (progenies of natural beech stands) under changed climate situations in sets of pan European field trials. The results obtained will facilitate the joint evaluation of the genetic resources of beech for better economic utilization under observation of the requirements for a sustainable forest management. The MC5 and WGs meeting of the COST Action E52 has been held from the 17th to the 19th of April, 2008, in Florence (Italy). During this workshop oral presentations on beech have been given, and a selection of them is reported in the current issue of this journal.

A decade of European field trials with genetically modified plants

This article analyzes the development of notifications of genetically modified plants field trials in the European Union from 1991 to 2001, based on the data collected at the European level in the Summary Notification Information Format database. During this time period, a total of 1687 field trial notifications were received. The number of field trial notifications dropped by 76% between 1998 and 2001, mainly due to the de facto moratorium in place since 1999. Input traits (77%) dominated the field trial notifications during the last decade, while output traits were relevant in only 18% of all notifications, with a decreasing relevance during the last six years. In particular, field trial notifications on molecular farming were almost absent in the EU. Large companies focused their field trials on crops with a high grown area in the European Union and resistance traits, while public institutions showed interest in a large diversity of plants and traits. Finally, some conclusions on future impacts of the results of the study are drawn in this article.

Vaillant, Plug install PEM heating systems in European field trial

Vaillant, Plug install PEM heating systems in European field trial

Short-rotation forestry – operations, productivity and costs based on experience gained in the UK

Large-scale field trials of short-rotation coppice with willow and poplar have been studied since the mid-1980s in the UK. The information and results gained from these trials are presented, particularly with respect to operations, productivity and costs. Current methods for site selection, establishment, management practice, pests and diseases, harvesting and storage of short-rotation coppice crops are described and discussed. In the UK, the ability of short-rotation coppice to compete with conventional agricultural crops is still heavily dependent on the subsidies available for short-rotation coppice and the crop in question. Analysis of a wide range of data from field trials in Europe and North America showed that average levels of productivity ranged from 2 to 13.5 odt/ha/year. The assumption that short-rotation coppice productivity increases from the first to second and subsequent rotations is not borne out in practice. Productivity levels may be increased in future through improved management practice and clonal materials, but it is unlikely that the predictions made in the early 1980s will be achieved in practice.

An Expandable-Slotted-Tubing, Fiber-Cement Wellbore-Lining System

Summary An expandable-slotted-tubing, fiber-cement wellbore-lining system has been developed. Its purpose is to temporarily secure the integrity of a wellbore section to allow drilling operations to continue through deeper overpressured or depleted zones. The lining is installed below the previous casing with no or minimal reduction in hole diameter. The technology makes it possible to realize major reductions in well costs by avoiding the use of certain intermediate and contingency casing strings. It also helps in high-pressure/high-temperature (HPHT) well designs where the requirement for additional casing strings may become excessive. The paper outlines the technologies involved and installation/ evaluation procedures. Details are given of onshore and offshore field trials in Europe and the U.S.