Roberto Ruggeri

As climate change intensifies drought across the Mediterranean basin, safeguarding durum wheat, a cornerstone of regional agriculture, is a global priority. This study evaluated the efficacy of a novel biostimulant, containing glycine betaine, vaterite, and Pseudomonas protegens , with a specific focus on a critical factor: the application timing. To distinguish preventive (pre‐stress) and restorative (post‐stress) strategies, the treatment was applied either before or after drought induction in drought‐sensitive durum wheat seedlings. Drought severely inhibited growth, increased lipid peroxidation, and altered nutrient profiles. The effect of the biostimulant was highly dependent on application timing. Pre‐stress application mainly induced tissue‐specific metabolic and oxidative responses. In contrast, post‐stress treatment promoted recovery of shoot biomass to values comparable to well‐watered controls and was associated with increased stomatal density and leaf greenness relative to untreated drought‐stressed plants. Post‐stress treatment also produced a root morphological profile closer to that of control plants and a shoot ionomic pattern more similar to well‐watered plants. Selected stress‐responsive genes showed lower transcript levels in biostimulant‐treated than in untreated drought‐stressed plants, indicating treatment‐associated changes in the expression of specific stress‐related pathways during recovery. These findings highlight post‐stress biostimulant application as a promising timing‐dependent strategy to support the recovery of drought‐sensitive durum wheat seedlings.

Background: Territorial food production is a well‐known quality trait, which is attracting new customer preferences for different agricultural products. In this context, many microbreweries and agricultural breweries started to cultivate their own small hopyard to exploit the so‐called “terroir” effect. Despite this interest, the number of studies that explore the effect of the environment on hop yield and quality is limited, especially in new growing areas that are developing around the world. The aim of this study was to evaluate the effect of growing location on yield performance and alpha and beta acid content of Cascade hops cultivated along Italy. Results: Results from this case study showed that the cultivation area significantly affected both cone yield and quality traits of Cascade hops. Overall, hops that are cultivated in soils with higher content of fine particles and at lower latitudes had better quality features compared to those cultivated in lighter soils and at higher latitudes; namely, a greater alpha‐acid content (7% vs. 4%), lower cohumulone to total α‐acid content (27% vs. 30%), and higher α‐acid/β‐acid ratio (1 vs. 0.6). Beta acid content was relatively high (approximately 7%) and stable across all locations, while total resin content decreased with increasing latitude (from 14.4% to 10.9%). Cone yield ranged from 250 g plant ⁻¹ to 441 g plant ⁻¹ , without any apparent relation with soil texture or growing latitude. Conclusions: These findings can help researchers and brewers to better understand and predict the complex relationship existing between territory and agronomic performance and quality traits of Cascade hops.

Foliar application of biostimulants can be a valid option to reach the goal of sustainable intensification in agriculture, especially in extensive crops such as durum wheat. However, due to the wide range of active ingredients and their mixtures available in the market, the need to select the most efficient product in a specific growing environment is of dramatic importance to achieve remarkable results in yield and grain quality. To analyze the potential of different active ingredients, a field trial was performed in two consecutive growing seasons (2023 and 2024) under Mediterranean climatic conditions. A randomized block design with three replicates was used. Durum wheat cultivar “Iride” was treated with the following five foliar biostimulants in comparison with the untreated control (T0): seaweed and plant extracts (T1); micronized vaterite (T2); culture broth of Pseudomonas protegens (T3); humic and fulvic acids (T4); organic nitrogen fertilizer (N 5%) containing glycine betaine (T5). Biostimulant treatment was applied at the end of tillering and at heading. Root length, chlorophyll content, grain yield, yield components and grain quality were measured and subjected to a one-way analysis of variance. As compared to the control, seaweed and plant extracts as well as micronized vaterite showed the best results in terms of grain yield (29% and 24% increase, respectively), root length (120% and 77% increase, respectively) and grain protein content (one percentage point increase, from approx. 12% to 13%). The results from this study can help Mediterranean farmers and researchers to develop new fertilization protocols to reach the goals of the “Farm to Fork” European strategy.

Plants need to be fed to produce enough grains and fruits to meet human demands. Humans have been pursuing more efficient and green agricultural inputs to meet the nutritional needs of plants, and have also been constantly updating the outdated application methods to enhance the absorption of nutrients in plants. Historically, the transformation of organic manure to chemical fertilizer as the dominant substance for plant nutrition is closely related to the Industrial Revolution. The Industrial Revolution promoted the development of the chemical industry, providing the technology and equipment needed for the mass production of chemical fertilizers. The emergence and application of chemical fertilizers have also greatly increased plant productivity, supporting global population growth and urbanization process, which in turn furthered the development of the Third and Forth Industrial Revolutions. Today, urban agriculture and vertical farms are also gradually emerging, and these new scenarios also require new nutrient management models. Meanwhile, plant biostimulants and biochar are two emerging categories of agricultural inputs related to plant nutrition. Plant biostimulants are expected to become the third major type of agricultural chemicals after chemical fertilizers and pesticides. Besides being used as a soil conditioner and for environmental remediation, biochar is also expected to become an indirect nutrient input for enhancing crop productivity. Novel materials, such as coating material, nanomaterials, metal-organic frameworks (MOFs), covalent organic frameworks (COFs), hydrogen-bonded organic frameworks (HOFs), and crystalline porous organic salts (CPOSs), have also been used to regulate chemical fertilizers for plant efficient absorption. Of course, organic fertilizers continue to be applied worldwide, and their effectiveness is usually enhanced by adding better microbial agents and combining them with chemical fertilizers and biochar (Rathinapriya et al.). Plant physiologists, microbiologists, soil chemists, and other researchers need to explore the mechanisms of action in greater depth, such as how these substances are efficiently absorbed, transported, and utilized by plants, and how they function to promote growth, enhance stress resistance, and improve yield and quality (Cai et al.). By revealing these mechanisms, agricultural chemists could further optimize the formulas and application methods of these products, which is also conducive to the development of more targeted, efficient, and sustainable products. This topic covered the application effects and action mechanisms of various agricultural inputs, such as biochar, microbial fertilizers, straw, manure, slow-release fertilizers, plant biostimulants, and nanoparticles, on different crops and under various environmental stress conditions, providing rich scientific data and theoretical support for research in related special fields.During open submission period, we noticed that the live data on views and articles for our Research Topic were consistently the highest among open submission topics. We also found that there are many research topics similar to ours. As of January 18, 2025, among all 1918 research topics featured in the journal, 28 manuscripts were included in our Topic, ranking 68th; The total number of contributing authors stand at 209, ranking 35th. The authors came from 21 countries on all continents except for Antarctica. All these showed that this Topic is indeed a global hotspot in the research field of plant sciences. The scale of peer-reviewed papers from China has ranked first globally since 2021, and the same was true for our Topic. Collected manuscripts with Chinese first authors or those involving Chinese authors accounted for about half. Of course, the number of rejected manuscripts with Chinese first authors was also the largest after the peer review process. Cross-national collaborative research was not very common. This might be primarily due to the fact that many agrochemicals are still in the stage of experimentation or serving local demands, and the hardware research conditions required for the Topic Research could be met locally. This also reflected that although our Topic was a hotspot, the relative depth of research and the level of international research have not yet reached a high standard. In terms of article types, apart from the original research articles, a review and a meta-analysis paper had also been accepted for publication.Globally, nitrogen fertilizer is of utmost importance and attracts the highest number of research papers, followed by phosphate fertilizer. In contrast, potassium fertilizer has not received as much attention, with only one article submitted on this topic. Gopinath et al. verified POLY4 (a polyhalitebased fertiliser) can be serve as an excellent and environmentally friendly alternative to provide peanut (Arachis hypogaea) with all their necessary potassium nutrition. Based on the specific content of each article, we summarized that 9 articles related to biochar, 7 articles related to trace fertilizers and biofortification, 5 articles related to microbial and organic fertilizers, 4 articles related to biostimulants, fertilizer enhancers, and high-efficiency fertilizers, and research in other areas was relatively scattered.Biochar, as a sustainable soil amendment, can significantly enhance soil quality, carbon sequestration, and crop productivity, and alleviate the impact of abiotic stress on agriculture. Rathinapriya et al. systematically reviewed the production methods of different sources of biochar, its improvement effect on soil physical and chemical properties, and its promoting effect on growth of different crops and yield and quality performance under different abiotic stress conditions. In a sense, the other 8 articles on biochar could be considered as case studies. Under salt stress conditions, Gullap et al. found that biochar, derived from olive...

A better comprehension and analysis of climate impacts on crop traits allows the implementation of more appropriate adaptation strategies and, therefore, a higher resilience of the future cropping systems. The aims of this study were: (i) to assess how the climate changed in the last 32 years in a Mediterranean‐type climate, (ii) to understand how crop traits evolved over time in early and late durum wheat cultivars and (iii) to highlight which weather variables mostly affected the performances of diverse durum wheat varieties. To investigate this, a 32‐year period (i.e., 1989–2020) was analysed, detecting possible significant trends of weather variables (e.g., air temperatures, precipitations, solar radiation) and crop traits (e.g., earliness, yield, yield components and test weight) over time in Viterbo, central Italy. Eight durum wheat varieties (4 early and 4 late cultivars) were chosen from the most used in that location. A clear upward trend of the monthly maximum air temperature during the entire growing season was revealed (0.12°C–0.21°C per year), while rainfall displayed a significant trend only for February and March. Days to heading and number of spikes per unit area showed a significant downward trend moving towards 2020. Anticipation of heading date was much more pronounced in the late cultivars than in the early ones, so that the difference between the two groups was reduced from about 10 days of 1989 to less than 6 days of 2020. Grain yield stagnated around 5 t ha⁻¹ with late varieties that proved to be as good producers as the early ones. Test weight and thousand kernel weight showed a slight increase over time. Maximum temperatures of February and March exerted a considerable influence in reducing time to heading (0.7–3.4 days for each additional°C), while the maximum temperature of May was detrimental for grain yield (−180 to −270 kg ha⁻¹ for each additional °C). Our study identified two weak points in the current durum wheat cultivation: (i) phenology is being more and more similar among modern cultivars; (ii) the number of spikes per unit area dramatically decreased in the last 30 years. Therefore, beside greater genetic diversity, a new agronomic approach, especially from seeding to the end of the tillering stage, will be required to cope with durum cultivation in the future climate scenario of the Mediterranean. The outputs of our analysis add precious information on the comprehension of climate change effects on Mediterranean cropping systems and can guide either the decision making for the management of durum wheat or its breeding activity for the future.

A prompt seed germination and emergence coupled with an excellent seedling vigor are highly desired features to ensure perfect crop establishment and subsequent vegetative growth. Seed dressing with pesticides represents the most common technology for enhancing seed performance after sowing, while little is known about biostimulant seed dressing. This practice could play a fundamental role in developing new sustainable starter fertilization for cereals. The enhancement of germination and seedling vigor of durum wheat seeds (Triticum turgidum L. subsp. durum (Desf.) Husn) was the main target of this research. The experiment took place in a germination cabinet under controlled environmental conditions, settled at the constant temperature of 10 °C and under dark conditions for 8 days. The different seed dressings, sprayed on the seeds, were composed by a combination of a fungicide and different biostimulants. Coleoptile and root length, as well as biomass, were significantly increased by the different biostimulants, compared to the control. As for germination traits, seeds treated with Codium fragile and Opuntia ficus-indica extracts, containing phytohormones and different nutrients, showed a final germination (96%) significantly higher than the one obtained with the control treatment (86%). These results show that treating seeds with a suitable dressing solution can greatly improve the germination features and seedling vigor of durum wheat. This can help the crop to withstand future stresses, especially in early stages, and possibly increase the grain yield with a reduction in agrochemicals. However, the combination of the substances used in the present study rarely showed a synergistic effect on the tested variable.