Search Results (219)

Mathematical modelling, including the use of response surface methodology (RSM), facilitates the analysis of complex relationships between various extraction process parameters and the bioactive properties of plant extracts. The aim of this study was to optimise selected parameters of the ultrasound-assisted extraction (UAE) process of the herb Trifolium pratense L. to yield extracts with high antioxidant activity (AA-DPPH) and total polyphenol content (TPC). The following parameters were investigated: solvent selection (methanol, ethanol, isopropanol, and n-propanol), the alcohol concentration used as the solvent (from 20% v/v to concentrated), and extraction time (2–15 min). The optimal extraction conditions, depending on the solvent used, comprised alcohol concentrations of 49–61% v/v and extraction times of 3–13 min. Under these optimal conditions, the extracts exhibited high antioxidant activity (methanol 4.21 ± 0.02, ethanol 3.92 ± 0.02, n-propanol 3.84 ± 0.02, and isopropanol 3.72 ± 0.02 mmol Trolox/L) and high total polyphenol content (n-propanol 0.84 ± 0.01, ethanol 0.81 ± 0.01, isopropanol 0.76 ± 0.01, and methanol 0.72 ± 0.01 g GA/L). The log p value of the optimised extracts was below zero (except for the isopropanol extract), indicating their hydrophilic nature, which is attributed to the presence of polar phenolic compounds. The extracts obtained via optimised UAE were characterised by a high content of bioactive compounds with antioxidant potential, suggesting their potential application in the pharmaceutical and cosmetic industries. Full article

Maize is one of the most widely grown and used crops in the world. Nowadays, weather anomalies such as drought and sudden heavy rains due to climate change bring up serious challenges to maize production. One environmentally conscious approach that contributes to climate change resilience is cover cropping. In the production technology of corn-legume cover crops, corn as the cash crop was examined in two ways in a field small-plot experiment in four repetitions in randomized block design plots. In one case, the legume cover crops were sown as an interseeding cover crop in a corn monoculture; in the other case, the crop rotation agrotechnique was applied to what CCs could be included in the cereal-maize crop rotation after winter cereals. The experiment was set up in Vertisol and Chernozem. In all cases control treatment was included. Our results showed that pea vine and cowpea contributed to increased corn yield on both soil types and agrotechniques. White sweet clover cannot be recommended as a cover crop because this seemed too competitive with the cash crop. Field pea is recommended for the crop rotation agrotechnique. Trifolium species like Persian clover, red clover, and crimson clover show good adaptability to Vertisol. Full article

Intercropping maize with legume cover crops has been shown to increase soil organic carbon (SOC) and alter soil microbial communities, potentially affecting soil aggregate stability. However, whether different legume cover crop varieties vary in their effects on SOC enhancement and aggregate stability improvement, and whether such variation is associated with their capacity to enhance distinct microbial taxa, remains unclear. Here, we conducted a five-year field experiment comprising maize monoculture (MM) and six intercropping systems in which maize was grown with different legume cover crop varieties. We aimed to assess the role of bacterial, non-AMF, and arbuscular mycorrhizal fungal (AMF) community composition in influencing SOC and aggregate stability, measured as mean weight diameter (MWD). On average, the six intercropping systems significantly increased SOC by 28% compared with MM, with no significant differences among legume varieties. However, MWD varied significantly depending on the specific legume used. Specifically, intercropping with red clover or sesbania resulted in MWD values similar to MM, whereas intercropping with soybean, hairy vetch, common vetch, or yellow sweet clover led to significantly higher MWD. Notably, MWD was positively correlated with the proportion of C within macroaggregates (>0.25 mm), and this effect was linked to the enrichment of specific microbial taxa—including the bacterium RB41, the non-AMF Trichoderma, and AMF (unclassified Glomerales, Glomus2, and Glomus3)—in systems with high MWD. These findings indicate that while SOC accrual under intercropping is robust across legume varieties, aggregate stability is contingent upon the identity of the legume and its associated microbiota. Selecting legume varieties with a greater ability to increase the abundance of specific microorganisms that enhance C allocation into macroaggregates can simultaneously improve both SOC accumulation and aggregate stability in maize-based intercropping systems. Full article

Red clover (Trifolium pratense L.) is a crop used as a forage that possesses an exceptional nutritional profile and digestibility. Unfortunately, this crop has low seed yield. Within the framework of the “Legume Generation” EC-funded project, our team aimed to investigate the role of foliar boron application on pollen viability and pollen tube development, and to assess its overall effect on red clover cultivation. Plants of six commercial diploid red clover cultivars, Nika 11, Sofia 52, AberClaret, Milvus, Global, and S123, were field-grown and boron-treated by spraying with the commercial product “Lebasol”, 11% active water-soluble boron. To reach our purpose, the transcript levels of genes related to flower, pollen, and pollen tube development and boron transport were measured by qRT-PCR; pollen grain viability and count were assessed microscopically. For this research, eight genes were selected: Auxin Response factor (TprARF17); TprAPETALA3; Walls are thin (TprWAT1 and TprWAT2); NIPs genes (Nodulin Intrinsic Protein) TprNIP4;2, TprNIP7;1, TprNIP5;1, and TprNIP6;1. Additionally, total nitrogen content in leaves detached from field-grown boron-treated and untreated plants was assessed and compared with the expression levels of two TprNIP5;1 and TprNIP6;1 transporters. The fresh and dry biomass weight from the first and second cuts was evaluated, as well as the seed collected from the red clover plants. Seed germination percentage and vigor of seedlings were examined in vitro for both boron-treated and untreated groups of two specific cultivars. Collected data confirm that foliar application of boron affects pollen viability and plant development of red clover in the cultivation conditions of South East Europe. Full article

Managing weeds and improving soil health are priorities for South Dakota vegetable farmers. Clover (Trifolium spp.), used as a living mulch within and along cash crop rows, may aid in weed suppression and prevent soil erosion. However, prior research has shown living mulch often leads to yield decreases in cash crops. Research conducted in eastern South Dakota investigated the effects of four clover and four in-row soil management treatments on small-scale broccoli production. Whole plots of red (Trifolium pratense), white (Trifolium repens), and white × kura (Trifolium repens × ambiguum) clovers were direct-seeded in early spring; each clover plot and a bare ground control included four in-row management treatments: no-till + fabric, tilled + fabric, no-till, and tilled. Clover and weed growth were measured throughout the season. During the establishment year, 12.8 cm of precipitation was received, which effectively established the clover living mulch plots. However, in 2023, 5.6 cm of precipitation was received, which negatively affected the clover living mulch plots and created favorable conditions for weeds to outcompete the clover and broccoli. The results highlight the potential challenges and opportunities for managing clover cover crops as a living mulch during the first year of establishment in organic broccoli production. Full article

Silage additives formulated with lactic acid bacteria (LAB) are commonly applied to enhance fermentation efficiency and aerobic stability. However, comparative evaluations across different forage species are still scarce. This in vitro experiment assessed the influence of eleven commercial silage inoculants containing various combinations of homo- and heterofermentative LAB on fermentation dynamics, nutrient conservation, and aerobic stability of medium-wilted alfalfa (Medicago sativa L.), perennial ryegrass (Lolium perenne L.), and red clover/perennial ryegrass silages. Experimental silages were prepared in 3 L laboratory silos and stored for 90 days. All inoculated treatments exhibited significantly lower pH values at both 3 and 90 days of ensiling compared with the untreated control (p < 0.05). LAB application increased the concentration of total fermentation acids and lactic acid in all forage types, although responses varied depending on inoculant composition. Inoculants containing Lentilactobacilllus buchneri produced the greatest acetic acid concentrations and resulted in a marked enhancement of aerobic stability. Compared with the control, silage inoculation significantly decreased dry matter losses by 35–64% and ammonia-N proportion by 20–37%, leading to an additional dry matter recovery of 1.29–2.87%. Control silages showed the lowest aerobic stability (97.2 h), while inoculated silages ranged from 126.0 to 200.4 h, with the extent of improvement differing among forage species and LAB formulations. In conclusion, commercial silage inoculants incorporating diverse LAB strains effectively improve fermentation quality, limit nutrient degradation, and enhance aerobic stability of legume and grass silages under controlled experimental conditions. Full article

Endophytic fungi can influence plant development through diverse molecular mechanisms; however, their volatile organic compound VOC-mediated effects on agriculturally relevant crops remain insufficiently characterized. In this study, we examined the effects of VOCs produced by six grass-root-associated endophytic fungi—Cadophora fastigiata, Cordyceps fumosorosea, Chaetomium funicola, Epicoccum nigrum, Microdochium bolleyi, and Plectosphaerella cucumerina—on early growth of spring barley (Hordeum vulgare) and red clover (Trifolium pratense). In plate-in-plate VOC exposure assays, we assessed root system traits, root hair formation, and biomass accumulation. Responses to fungal VOCs were fungal species-specific but similar across barley and red clover. VOCs emitted by C. fastigiata and P. cucumerina were consistently associated with increased root growth, root hair proliferation, and seedling biomass, whereas VOCs from M. bolleyi and C. funicola resulted in neutral or growth-suppressing effects. A complementary seed inoculation experiment was conducted with barley, which showed fungal species–dependent contrasting effects consistent with the observations of VOCs treatment. Gas chromatography–mass spectrometry (GC–MS) analysis revealed that C. fastigiata, the isolate associated with the strongest growth-promoting responses, emitted a diverse VOC profile dominated by sesquiterpenes, with 22 compounds identified. Together, these results demonstrate that VOCs emitted by grass-root-associated endophytic fungi exert reproducible, species-specific effects on early plant development occurring in phylogenetically distant species. The findings highlight the value of VOC-based assays for comparative functional screening of fungal isolates, providing a foundation for future studies that aim to link individual VOCs to plant growth responses. Full article

Red clover (Trifolium pratense L.) is a rich source of isoflavones with documented antioxidant and skin-protective properties, yet substantial differences in phytochemical composition exist among cultivars. In this study, fourteen T. pratense cultivars were compared with respect to formononetin and biochanin A contents (Milena, Pasieka, Pyza, Milvus, Nemaro, Maro, Larus, Hammon, Vesna, Fregata, Carbo, Forelia, Osimia, and Elanus), and the relationship between isoflavone profiles and skin-related biological activity was evaluated. High-performance liquid chromatography revealed pronounced cultivar-dependent variability with formononetin and biochanin A contents ranging from 1.60 to 7.80 mg/g DW and from 0.69 to 6.44 mg/g DW, respectively. The observed variability was further visualized by principal component analysis. The cultivar with the highest total isoflavone content—Hammon, was selected for biological assessment. Its extract exhibited antioxidant (DPPH IC₅₀ = 0.619 mg/mL; FRAP IC_0.5 = 0.302 mg/mL) and enzyme inhibitory activities (elastase IC₅₀ = 0.602 mg/mL, hyaluronidase IC₅₀ = 22.44 mg/mL), and it significantly enhanced fibroblast migration in an in vitro scratch assay, indicating anti-aging and regenerative potential. These results demonstrate that red clover cultivars differ significantly in their suitability as sources of bioactive isoflavones and highlight the importance of cultivar selection for the development of standardized plant-derived anti-aging ingredients. However, it is worth emphasizing that isoflavones derived from red clover are a valuable group of active compounds with significant potential for topical application as anti-aging and regenerative agents, warranting further formulation development and in vivo validation. Full article

High-temperature stress adversely affects the yield and quality of red clover (Trifolium pratense). However, the molecular mechanisms underlying red clover’s heat tolerance remain incompletely understood, which limits targeted genetic improvement. This study employed a multi-omics approach to compare a heat-tolerant cultivar (“HL”) and a heat-sensitive cultivar (“Tp615”). Under high-temperature stress, “HL” exhibited superior physiological adaptation, showing 1.8 times higher chlorophyll retention compared to “Tp615.” Transcriptome analysis identified 3104 core differentially expressed genes, including 175 transcription factors, with qRT-PCR validation confirming expression patterns consistent with the transcriptomic data. Broad-targeted metabolomics revealed 1242 differentially accumulated metabolites. Multi-omics integration highlighted the crucial role of the phenylpropanoid biosynthesis pathway in enhancing red clover’s heat tolerance. This study deciphers the mechanisms underlying red clover’s heat resistance and offers valuable genetic resources and a theoretical foundation for breeding stress-tolerant forage crops. Full article

A field experiment was conducted in 2019–2020 and 2020–2021 at Rogoza, Fala, and Brežice in Slovenia to examine the biological viability of a mixed intercropping system and the effect of winter catch crops (WCCs) on maize growth parameters. The experiment included Italian ryegrass (IR) in pure stands, fertilized with nitrogen (N) in spring (70 kg N ha⁻¹), mixtures of crimson clover and red clover 50:50 (C), and intercropping between IR and C (IR+C). Neither mixture was fertilized with N in spring. We evaluated different competition indices and biological efficiency. Relative crowding coefficient (RCC) and actual yield loss (AYL) exceeded 1, indicating a benefit of IR+C intercropping. The IR in intercropping was more aggressive, as indicated by positive aggressivity (A) and a competitive ratio (CR) > 1, and it dominated over C in IR+C (that had negative A values and CR < 1). The competitive balance index (Cb) differed from zero, the relative yield total (RYT) was 2.24, the land equivalent coefficient (LEC) exceeded 0.25, the area–time equivalent ratio (ATER) exceeded 1, and land use efficiency (LUE) exceeded 100%. IR+C exhibited the highest total aboveground dry matter yield of maize (29.22 t ha⁻¹), the highest nitrogen content in dry matter grain yield of maize (206.35 kg ha⁻¹), the highest nitrogen and potassium content in maize stover (105.7 and 105.7 kg ha⁻¹, respectively), and the highest nitrogen and potassium content in the total aboveground dry matter of maize (312 and 267.3 kg ha⁻¹, respectively). The C/N ratio in dry matter yield of IR was 45.35, and in IR+C it was 33.43, which means that the mixture had a positive effect on nutrient release in maize. The ryegrass–clover mixture, according to the calculated biological indices, had advantages over pure stands and had a positive effect on maize yield. Full article

The implementation of vegetative cover crops in vineyards is a sustainable alternative to chemical weed control, potentially influencing both soil fertility and grape-associated microbiota. This study evaluated the impact of six groundcover management strategies under vines—white clover (Trifolium repens), red clover (Trifolium pratense), burr medic (Medicago polymorpha), lupine (Lupinus albus), spontaneous weeds, and an herbicide-treated control—on the microbial dynamics and physicochemical properties of Cabernet Sauvignon must and wine from the Maipo Valley, Chile. Amplicon sequencing of bacterial (16S rRNA) and fungal (ITS) communities was combined with spontaneous fermentation trials and chemical analyses of must and wine. Fungal and bacterial communities on grape surfaces were dominated by Ascomycota and Proteobacteria, respectively, with no significant compositional differences among treatments. During fermentation, Metschnikowia and Tatumella were the most abundant non-Saccharomyces and bacterial genera, respectively, showing dynamic shifts across fermentation stages. Legume-based covers, particularly red clover, increased wine total acidity and polyphenol index while reducing pH. Correlation analyses revealed associations between specific microbial taxa (Metschnikowia, Cohnella, Saliterribacillus) and key enological parameters. Overall, these findings demonstrate that leguminous cover crops subtly modulate vineyard microbial ecology and fermentation outcomes, offering an environmentally sustainable pathway to enhance enological differentiation in semi-arid viticultural regions. Full article

Plant growth-promoting bacteria (PGPB) can act as biostimulants, improving the growth of plants in sustainable agriculture systems that seek to reduce synthetic agrochemical input. Bacteria present in seeds are closely associated with vertical transmission and thus represent a potential trove of biostimulants. Capsicum species are notable for producing capsaicin, a compound with antimicrobial activity that may influence microbial communities associated with pepper fruits and seeds. Using Luria–Bertani (LB) media infused with capsaicin, we isolated bacteria from bell peppers, jalapeno peppers, and habanero peppers, which we verified to have different levels of capsaicin through high-performance liquid chromatography with ultraviolet detection (HPLC-UV). Minimum inhibitory concentration (MIC) assays indicated that the capsaicin resistance of isolated bacteria did not correlate with the pungency level of the host pepper variety. Of the total isolated bacteria, four showed promise as plant growth promoters; two belong to the genera Pseudomonas, one Agrobacterium, and one Bacillus. Our isolates tested positively for potassium and phosphate solubilization, urease production, and indole-3-acetic acid (IAA) phytohormone production. Inoculation of these bacteria into surface-sterilized red clover (Trifolium pratense) and Kentucky bluegrass (Poa pratensis) showed significant improvements in germination rate, seedling root length, and seedling shoot height. These results show that the pungency of peppers does not influence the capsaicin resistance of isolated bacteria. Additionally, seedborne PGPB have the potential for plant growth improvement through various mechanisms, reducing the need for synthetic chemicals. Full article

Mixed cropping may positively affect soil fertility and soil biological activities, such as those related to mycorrhizal colonization intensity (M%), which plays a vital role in the plant nutrient cycle and can improve tolerance to drought and pathogens. This plant and soil fungi symbiosis helps to reduce dependency on chemical fertilizers, promotes sustainable agricultural practices, and minimizes environmental impacts. However, field studies that clearly assess the effects of cereal/legume intercropping on mycorrhizal intensity and relate it to plant productivity, yield quality, and plant adaptation to climate change are lacking. This field experiment was conducted to assess the effects of cereals/legume intercropping on mycorrhizal colonization, and to explore its interaction with physical cereal root parameters and crop yield. Three main crops, spring barley, oat, and field pea, were grown as monocultures. For the spring barley and oat, the study also included two different fertilization levels (with and without organic fertilizers) and legume intercropping (field pea and red clover). The intercropping had a significant impact on spring barley and oat root length, diameter, and specific root length. The general average of root length and diameter was higher in oat–pea and barley–pea cropping systems. The most significant effect in root architecture parameters observed in red clover was when it was intercropped with barley or oat. The establishment of field pea intercrop significantly increased M% in spring barley and had a positive effect on the grain yields of both spring barley and oat. Meanwhile, red clover intercropping enhanced M% and grain yield in oats but had no such effect in barley. In both spring barley and oat, M% was positively correlated with grain yield. Full article

Background/Objectives: Interindividual variability in polyphenol metabolism may help explain the inconsistent effects of polyphenol intake on health outcomes. This study compared, for the first time, (i) polyphenol-related gut microbiota metabotypes (urolithins: UM0, UMA, UMB; equol: EP, ENP; lunularin: LP, LNP) and their clusters (MCs) in non-medicated premenopausal (Pre-M) and postmenopausal (Post-M) women and (ii) the impact of an 8-week intake of a polyphenol-rich plant extract mixture (PPs) on the quality of life (QoL) of Post-M. Methods: Polyphenol metabotypes were determined in urine via UPLC-QTOF-MS after a 3-day intake of PPs containing resveratrol, pomegranate (ellagitannins and ellagic acid), and red clover (isoflavones) in Pre-M (n = 120) and Post-M (n = 90) women. QoL was assessed with the short-form Cervantes Scale in a randomized, placebo-controlled crossover trial (8-week PPs vs. placebo), completed by 78 Post-M participants. Results: At baseline, Pre-M and Post-M women showed only minor differences in metabotype and MC distributions linked to menopausal status. MC3 (UMA+EP+LP) predominated in Pre-M, while MC7 (UMA+EP+LNP) was most frequent in Post-M. PPs intake in Post-M women led to modest shifts in metabotype and MC distributions toward Pre-M patterns. Quantitative metabolite production was comparable between groups, except for equol, which showed a median 2.8-fold increase after PPs intake in EP Post-M women. Clinically meaningful improvements (score reduction ≥ 6.7 points) in QoL were observed in the Psychic domain in EP women (28%, p = 0.039) and in the Menopause and Health domain, specifically in EP (24.1%, p = 0.004), MC3 (22.5%, p = 0.043), and MC4 (UMB+EP+LP; 41.3%, p = 0.022), were mainly driven by a reduction in hot flashes (p = 0.001). Conclusions: These findings support metabotyping as a tool to guide targeted dietary strategies and enhance QoL through precision health in Post-M women. Full article

Cover crop mixes play an important role in enhancing soil health, nutrient turnover, and ecosystem resilience; yet, maintaining even seed dispersion and planting uniformity is difficult due to significant variances in seed physical and aerodynamic properties. These discrepancies produce non-uniform seeding and species separation in drill hoppers, which has an impact on stand establishment and biomass stability. The thousand-grain weight is an important measure for determining cover crop seed quality and yield since it represents the weight of 1000 seeds in grams. Accurate seed counting is thus a key factor in calculating thousand-grain weight. Accurate mixed-seed identification is also helpful in breeding, phenotypic assessment, and the detection of moldy or damaged grains. However, in real-world conditions, the overlap and thickness of adhesion of mixed seeds make precise counting difficult, necessitating current research into powerful seed detection. This study addresses these issues by integrating deep learning-based computer vision algorithms for multi-seed detection and counting in cover crop mixes. The Canon LP-E6N R6 5D Mark IV camera was used to capture high-resolution photos of flax, hairy vetch, red clover, radish, and rye seeds. The dataset was annotated, augmented, and preprocessed on RoboFlow, split into train, validation, and test splits. Two top models, YOLOv5 and YOLOv7, were tested for multi-seed detection accuracy. The results showed that YOLOv7 outperformed YOLOv5 with 98.5% accuracy, 98.7% recall, and a mean Average Precision (mAP 0–95) of 76.0%. The results show that deep learning-based models can accurately recognize and count mixed seeds using automated methods, which has practical applications in seed drill calibration, thousand-grain weight estimation, and fair cover crop establishment. Full article