DAY 2Wednesday, 3 December 2025

Agricultural input companies involved in biostimulant development frequently accumulate multi-year, multi-regional trial datasets but often fail to synthesize these into a coherent technical positioning strategy. This fragmented approach leads to inconsistent internal planning, limited product differentiation, and weak credibility among clients and stakeholders. Decision-making commonly depends on cherry-picked or incomplete data, resulting in misleading claims and user skepticism in a saturated, undifferentiated market.A structured, stepwise analytical framework can address these challenges. It begins by defining focused, high-level questions around product performance, followed by rigorous data standardization and quality control. Descriptive and multivariate analyses are then applied to uncover patterns in performance across variables such as crop, rate, timing, and treatment combinations.The ability to benchmark enables the contextualization of new data against product classes across diverse geographies, offering a reality check on efficacy claims. Such benchmarking can identify potential biases or anomalies in trial design and guide future product development strategies grounded in comparative performance.Integrating environmental datasets—soil and weather — and linking to individual trial locations allows for modeling of product efficacy in relation to specific environmental conditions, revealing where and under what circumstances treatments perform optimally or underperform. These insights support predictive technical positioning strategies that align commercial and technical teams around a shared, evidence-based understanding of product behavior. The resulting Best Management Practice (BMP) meets the number one need market research has verified among farmers around the world over the past 35 or 40 years – BMPs from independent sources.

Over the past three decades, SEGES Innovation, in collaboration with the Danish Technological Institute, has conducted an extensive series of field trials to evaluate the impact of plant biologicals (PBs) across diverse cropping systems and pedoclimatic conditions in Denmark. The results of these years of research in farmers' fields have been synthesized into a comprehensive dataset. More than 35 field trials, encompassing over 205 treatments, are being assessed to quantify the effectiveness of various PBs on crop yield, yield quality, and biomass production.The study employs meta-regression to correlate treatment outcomes with soil texture, soil organic carbon, nitrogen levels, and other site-specific variables. It also categorizes effects based on crop type (cereals, legumes, vegetables, grasses, tubers), PB function (nutrient availability, plant protection, growth promoters), and dosage application. The dataset offers several unique traits that strengthen the methodology of testing biologicals within the Danish context: the data is tested under farmer-relevant conditions, with standardized sampling regimes, and with high-resolution of within-field variability. Field results are unbiased and published annually in the Landsforsøgene®, a booklet where Danish farmers and advisors can check latest advancements in agronomy.This work not only highlights the potential of PBs to support crop yields and soil health but also contributes to the development of improved field trial protocols tailored to northern European contexts. Current efforts are focused on data harmonization to enhance interpretability and practical recommendations.

The effects of biostimulant compounds are often small, and detecting them during screening presents significant challenges. Small sample sizes, a limited set of parameters, and a reliance on endpoint measurements increase the likelihood of missing these effects. This often leads to uncertain decisions, repeated experiments, and the exclusion of promising candidates (false negatives).

The project ST POL ((Carnot Agrifood Transition Institute 2024-2026) aimed to 1/ establish a comprehensive study protocol for thermal stress 2/ evaluate a potential correlation between pollen quality and fruit development in order to predict yield at early stage and 3/ identify biostimulant able to alleviate plant thermal stress by maintaining good pollen qualityThe protocol was developed on a vegetable crop with fruit valorisation (tomato) and a broadacre crop (spring wheat). Three types of stress were applied per crop, modulated in time (duration and photoperiod) and intensity (temperature), with a maximum temperature of 40°C. The stress intensity was characterized by several biochemicals markers : electrolyte leakage, proline, MalonDiAldehyde, Glycine betaine and Abscisic acid contents. The use of the qPFD® chip (INRAE license) also allowed monitoring the impact of thermal stress, with overexpression of genes related to the ethylene pathway.IFC technology (impedance flow cytometry) was used to monitor the quantity and viability of pollen. The different tested temperatures highlighted a loss of viability ranging from 10% to 100% in flowers subjected to stress. The correlation between pollen quality, fruit development, stress markers and yield is being analysed.A biostimulant product was identify, able to alleviate the thermal stress by protecting pollen quality and reduce the intensity of stress markers.

Modern agriculture must balance crop yield maintenance with the challenges of climate change and the need for sustainable practices. Plant biostimulants offer a promising solution to these issues but often face skepticism, likely due to limited knowledge about their composition and mechanisms of action. Among various factors, inter- and intra-specific plant diversity remain significant sources of variability for biostimulant efficacies. In this study, we investigate the impact of intra-specific variation in Arabidopsis thaliana on the effectiveness of Ascophyllum nodosum extracts (ANEs), known to enhance plant growth and tolerance to abiotic stresses1. The phenotypic variation among 54 natural A. thaliana accessions treated with ANEs under combined heat and water deficit stress was assessed using growth measurements and metabolomic analyses. The ANEs tested showed similar overall efficacy on growth, as measured by the number of accessions positively affected under stress conditions, with higher effectiveness in stress-sensitive accessions. Multivariate analysis of metabolomic data revealed a clear separation between biostimulated and control plants under stress, suggesting an intermediate metabolic state between non-stressed and stressed controls. Leveraging intra-specific response diversity, in-depth analysis identified a core set of metabolites associated with treatment effects and/or biostimulant efficacy. These findings highlight the dual nature of the biostimulation mechanism: a constitutive response triggered by the treatment itself, and accession-specific efficacy responses. Key metabolic traits involved include sugar utilization capacity, activation of defense pathways, and the balance between cell wall biosynthesis and secondary metabolism. Ongoing mutant-based studies further investigate the role of these regulatory trade-offs in determining biostimulant success.

Xylem is the most abundant tissue on Earth, and its development is a multicellular process under complex regulation. Previous studies have extensively revealed a conserved transcriptional regulatory mechanism of xylem development in land plants, especially in angiosperms, mediated by the master regulators, the VNS (VND-, NST/SND-, SMB (SOMBRERO)-related protein) family. Despite the comprehensive understanding of transcriptional regulations, the upstream intercellular signaling mechanism still remained largely unknown. Signaling peptides act as hormones to deliver short- or long-distance intercellular signals to govern complex developmental processes. Identifying signaling peptides is challenging due to their low abundance and the unknown cleavage sites required for release from precursor proteins, not to mention the investigation of their evolutionary roles across species. Consequently, very few peptides were evolutionarily characterized in vivo, especially long-distance signaling peptides. Here we present current largest peptidomic datasets from six species (maize, camphor tree, tomato, rose gum, soybean and poplar), totaling 12,242 peptides, selected from all representative evolutionary clades of angiosperms, including monocots, magnoliids, rosid eudicots, and asterid eudicots. A sap peptide was found to be identical across all six species and named as ASAP (angiosperm sap peptide), emerging as the most conserved peptide family discovered thus far. ASAP act as biostimulator to rapidly induce a series of protein phosphorylation involved in a VNS-mediated signaling cascade. This finding uncovers a key regulatory layer that had remained unidentified for decades, redefining our understanding of the control hierarchy in plant xylem development and promote the plant growth.

The increasing global population entails a high demand for food production. However, in recent decades, the number of heat waves have increased due to climate change, compromising crop production [1]. In plants, the reproductive phase, particularly the development of female gametophyte, is the most sensitive stage to high temperatures [2]. A study showed a link between the bioactive carbohydrates inside Ascophyllum nodosum extracts and reduced impact of high temperatures during the reproductive phase [3]. Likewise, Ecklonia maxima extracts have been characterized by their ability in improving fruit set and yield [4]. In this study, we simulated severe heat waves in controlled conditions for 15 days to evaluate the effectiveness of an Ascophyllum nodosum extract (ANE) and an Ecklonia maxima extract (EME) in reducing the impact of heat stress on flowering chilli peppers plants. Our results indicate that the ANE application reduced oxidative stress in leaves, which coincided with HSFA2, a key regulator of the heat shock response. In the main stems, the ANE induced the development of new xylem vessel elements and radial parenchyma, improving water transport and starch storage at high temperatures. Importantly the ANE protected pollen and ovule development after 15 days of heat stress, resulting in a 25% increase in marketable yield when compared to untreated plants or treated with the EME, which had little effect on the measured parameters. Considering the challenges of reducing the impact of heat stress on crop reproduction, the use of specific ANE biostimulants combined can be a feasible solution for growers.

Biostimulants, when properly applied to crops, can enhance the environmental and economic sustainability of cultivation practices. In this study, we investigated the effects of eK-lon MAX (EM), K-Adriatica biostimulant, in compliance with Regulation (EU) 2019/1009. eK-lon mAX is derived exclusively from the fronds of Ecklonia maxima, collected and processed at low temperatures using a proprietary method designed to preserve all naturally occurring bioactive compounds.In this work, we aimed to confirm that eK-lon MAX—an extract derived exclusively from Ecklonia maxima fronds and processed at low temperatures to preserve all bioactive components—induces transcriptional changes in tomato (Solanum lycopersicum L.). EM was applied at 14 g/L as a foliar spray. Leaf and fruit samples were collected at 6 and 24 h post-treatment. Differential gene expressions were evaluated in treated vs. control plants, followed by annotation and functional cluster analysis.Differentially expressed genes (DEGs) were associated with hormone-regulated pathways and with primary and secondary metabolism. Up- and downregulated DEGs displayed specific temporal expression patterns linked to treatment timing and tissue type.The effects are not due to the action of a single group of molecules, such as phytohormones, but rather to the synergistic activity of the entire set of bioactive compounds retained in the final product. Our findings provide strong evidence that biostimulant efficacy of eK-lon MAX is directly linked to its unique production method, which ensures the preservation of all bioactive fractions from the original fronds. This integrity is key to its ability to modulate transcriptional responses and enhance plant performance.

Plant growth-promoting rhizobacteria (PGPR) are increasingly used to enhance crop productivity and resilience against biotic and abiotic stresses. Despite their promise, PGPR-based products often show inconsistent effects in field conditions. While environmental factors are known to influence their efficacy, the role of interactions with native edaphic microbial communities (microbiota) remains underexplored, though potentially critical for PGPR survival, colonization, and bioactivity. Our study investigates how soil microbiota affect the growth-promoting potential of PGPR.We conducted an experiment under both gnotobiotic (sterilized) and non-gnotobiotic (non-sterilized) conditions using three Bacillus velezensis strains inoculated on spring wheat grown in three agricultural soils. Our results showed that PGPR significantly increased plant biomass in sterilized soils, but this effect was reduced or absent in the presence of native microbiota, suggesting competitive or antagonistic interactions.To expand these findings, we initiated a broader trial with 12 agricultural soils varying in physico-chemical properties and management histories. Preliminary results confirm that soil microbiota from diverse agrosystems shapes PGPR effectiveness. This work highlights the need to integrate microbial ecology into PGPR development and application strategies. Understanding PGPR-microbiota-plant interactions will be a key to improving the consistency and reliability of microbial inoculants in sustainable agriculture. We will present insights from our experimental design, results, and methodological framework aimed at unraveling these complex interactions.

Microbial inoculants are biotechnological products used for different purposes, the main one being to replace chemical fertilizers totally or partially, with an emphasis on N-fertilizers, reducing costs and decreasing the contamination of the soil, water, and atmosphere. Brazil has a long tradition in the use of rhizobia inoculants, especially for the soybean crop. In 2009 the first commercial inoculant carrying the plant-growth-promoting Azospirillum brasilense strains Ab-V5 and Ab-V6 reached the market. 13 years after the release of these two strains, 25 million doses were commercialized for grasses, including corn, wheat, rice, and pastures, and co-inoculation (the association of two or more species of inoculants) of legumes, such as soybean and common bean. Studies in Brazil have presented consistent results of increases in root growth, biomass production, grain yield, uptake of nutrients due to the inoculation with Ab-V5 and Ab-V6. In the soybean season 2023/24 in Brazil, the inoculation rate with Bradyrhizobium to promote biological nitrogen fixation (BNF) in soybean was 85%, which represents around 37 million treated hectares. The need of a continuous increase in yield to attend the soybean demand, stimulates farmers to adopt inputs that guarantee the appropriate supply of Nitrogen. Considering that soybean has around 65 kg of N per metric tonne of grain, it is very important to adopt tools that allow greater BNF efficiency. The most widely studied is the association of Bradyrhizobium with Azospirillum brasilense. In addition to being a N fixing bacterium, Azospirillum produces hormones, such as auxins, which stimulate the initial root hair formation. This effect allows the early formation of nodules and contributes to a greater number of nodules. All these benefits have been observed in many trials in Brazil. These results have had an impact on the adoption of co-inoculation in soybeans. According to Brazilian market research done by Kynetec, the co-inoculation technique was used in 18.0 million hectares in the soybean season 2023/2024, which represents an adoption rate of 41%, contributing to sustainable protein production.Keywords: Co-inoculation, Nitrogen; Azospirillum; BNF.

The relationship between plant nutrition and soil health is fundamental to sustainable and productive agriculture. While biostimulants are increasingly used to enhance crop performance, their efficacy is deeply influenced by the physical, chemical, and biological condition of the soil. This presentation explores how comprehensive soil analysis can be leveraged not only to optimize nutrient recommendations, but also to assess and improve soil health- an essential foundation for maximizing the benefits of biostimulant applications.
We will review key indicators of soil fertility such as cation exchange capacity (CEC), organic matter, pH, and macro- and micronutrient levels—and connect them with biological health markers, including microbial activity, enzymatic profiles, and redox potential (Eh). By integrating traditional soil chemistry with emerging biological diagnostics, we can develop more targeted, efficient, and regenerative fertilization strategies.
Real-world case studies from horticultural and field crop systems will be presented to illustrate how interpreting soil data through a health-centered lens results in improved plant nutrient uptake, stress tolerance, and productivity. The discussion will also highlight how soil amendments, cover cropping, and organic inputs can synergize with biostimulants when guided by soil diagnostics.
Ultimately, this talk advocates for a shift from treating soil as a mere substrate to managing it as a living, dynamic ecosystem. Participants will gain practical insights into how soil analysis can inform both nutritional and biological management decisions, paving the way for resilient, regenerative agriculture.

The current climate change is putting agricultural lands at higher risk of suffering from severe abiotic stresses, among which drought plays a major role. An emerging solution consists in the application of plant microbial biostimulants. Plant growth promoting (PGP) rhizobacteria are indeed able to improve crop yield and tolerance to both biotic and abiotic stresses. The main objective of this research is to describe how the rhizospheric and root endospheric microbiota is shaped by the imposition of drought stress, also analyzing its resilience after a recovery condition. Two different crops, tomato and rice, have been grown in a substrate made from a pool of soils often subjected to drought. Drought stress was gradually induced and then a rewatering phase was applied. Next-generation sequencing techniques allowed the microbial biodiversity description during drought stress and after the recovery phase. The results suggest a deep shaping of the microbial community, especially upon drought conditions, showing in particular a recruitment of Bacillus sp. Furthermore, bacteria belonging to Bacillus genus were isolated from rhizosphere and endosphere of both crops and their PGP abilities were analyzed through different assays (P solubilization, IAA and siderophores production, drought tolerance, ACC deaminase potential). The best performing bacterial strains were tested as inoculants in a greenhouse experiment under drought stress conditions, enhancing plant tolerance. The results obtained highlight the potential PGP abilities of the isolated strains, and will contribute to find new solutions, aimed at counteracting the rising climate changes, in a perspective of sustainable agriculture.

Above-ground plant organs are colonized by diverse microbial communities occupying distinct ecological niches: the phylloplane (leaf surface), caulosphere (stems), leaf endosphere (internal tissues), and the spicosphere—a complex ecosystem associated with cereal spikes. The composition and function of these microbiomes are shaped by plant species, environmental conditions, fertilization practices, and agrochemical inputs. These microbes play key roles in promoting plant resilience, growth, and yield formation.As part of the BioSafeFood project, co-financed by European Funds, we isolated and screened over 2,700 microbial strains collected from the phyllosphere of various crops. Comprehensive laboratory and field evaluations, conducted in collaboration with the Research Institute of Horticulture (InHort, Poland), enabled us to assess their biostimulant potential. Selected strains applied to leaf surfaces demonstrated strong capacity for colonization of both external and internal leaf tissues, including reproductive structures, and supported vegetative and generative development.Through genome analysis, we pinpointed functional genes likely contributing to their biostimulant properties. These involved in phenazine biosynthesis; genes for enterobactin synthesis, a siderophore that limits iron availability to microbial competitors; genes for auxin (IAA) biosynthesis, promoting plant growth and tissue differentiation.This presentation will summarize field and laboratory results, along with genomic insights into phyllosphere-associated mechanisms. Our findings confirm that precise selection and characterization of microbial strains inhabiting above-ground plant organs can provide a solid scientific foundation for microbiome-based strategies in sustainable crop production.