Search Results (145)

Several species of Fusarium are reported to infect inflorescences of high-THC-containing cannabis (Cannabis sativa L.) plants grown in greenhouses in Canada. These include F. graminearum, F. sporotrichiodes, F. proliferatum, and, to a lesser extent, F. oxysporum and F. solani. The greatest concern surrounding the infection of cannabis by these Fusarium species, which cause symptoms of bud rot, is the potential for the accumulation of mycotoxins that may go undetected. In the present study, both naturally infected and artificially infected inflorescence tissues were tested for the presence of fungal-derived toxins using HPLC-MS/MS analysis. Naturally infected cannabis tissues were confirmed to be infected by both F. avenaceum and F. graminearum using PCR. Pure cultures of these two species and F. sporotrichiodes were inoculated onto detached inflorescences of two cannabis genotypes, and after 7 days, they were dried and assayed for mycotoxin presence. In these assays, all Fusarium species grew prolifically over the tissue surface. Tissues infected by F. graminearum contained 3-acetyl DON, DON, and zearalenone in the ranges of 0.13–0.40, 1.18–1.91, and 31.8 to 56.2 μg/g, respectively, depending on the cannabis genotype. In F. sporotrichiodes-infected samples, HT2 and T2 mycotoxins were present at 13.9 and 10.9 μg/g in one genotype and were lower in the other. In F. avenaceum-inoculated tissues, the mycotoxins enniatin A, enniatin A1, enniatin B, and enniatin B1 were produced at varying concentrations, depending on the isolate and cannabis genotype. Unexpectedly, these tissues also contained detectable levels of 3-acetyl DON, DON, and zearalenone, which was attributed to apre-existing natural infection by F. graminearum that was confirmed by RT-qPCR. Beauvericin was detected in tissues infected by F. avenaceum and F. sporotrichiodes, but not by F. graminearum. Naturally infected, dried inflorescences from which F. avenaceum was recovered contained beauvericin, enniatin A1, enniatin B, and enniatin B1 as expected. Uninoculated cannabis inflorescences were free of mycotoxins except for culmorin at 0.348 μg/g, reflecting pre-existing infection by F. graminearum. The mycotoxin levels were markedly different between the two cannabis genotypes, despite comparable mycelial colonization. Tall fescue plants growing in the vicinity of the greenhouse were shown to harbor F. avenaceum and F. graminearum, suggesting a likely external source of inoculum. Isolates of both species from tall fescue produced mycotoxins when inoculated onto cannabis inflorescences. These findings demonstrate that infection by F. graminearum and F. avenaceum, either from artificial inoculation or natural inoculum originating from tall fescue plants, can lead to mycotoxin accumulation in cannabis inflorescences. However, extensive mycelial colonization following prolonged incubation of infected tissues under high humidity conditions is required. Inoculations with Penicillium citrinum and Aspergillus ochraceus under these conditions produced no detectable mycotoxins. The mycotoxins alternariol and tentoxin were detected in several inflorescence samples, likely as a result of natural infection by Alternaria spp. Fusarium avenaceum is reported to infect cannabis inflorescences for the first time and produces mycotoxins in diseased tissues. Full article

Records from 2012 to 2019 for two herds were analyzed to determine how tall fescue (Schedonorus arundinaceus (Schreb.) Dumont) endophyte (Epichloë coenophialum) status affected the productivity of spring-calving cows and calves. Pastures either contained tall fescue with wildtype endophyte (high levels of ergot alkaloids) or novel- or endophyte-free tall fescue (largely ergot alkaloid free). The experimental design was a randomized complete block with year as the replication unit. Forage samples from the farm with toxic endophyte-infected tall fescue contained 1136 ± 413 ppb total ergot alkaloids, while forage from the non-toxic pastures on the second farm contained 118 ± 83 ppb total ergot alkaloids. Artificial insemination pregnancy rates and calving rates were greater (p < 0.05) for cows that grazed non-toxic tall fescue (51.2 ± 2.8% and 93.5 ± 1.4%, respectively) than for cows on toxic endophyte-infected tall fescue (43.3 ± 2.8% and 88.8 ± 1.4%, respectively). Birth weights and weaning weights were greater (p < 0.05) for calves from the non-toxic tall fescue system (37 ± 1 kg and 278 ± 8 kg, respectively) than for calves from the toxic endophyte-infected tall fescue system (33 ± 1 kg and 254 ± 8 kg, respectively). Raising cattle on tall fescue without the toxic endophyte improved cow and calf productivity. Full article

Alluvial fan scree deposits (AFSDs) in arid/semi-arid regions are highly susceptible to rainfall-induced erosion, posing significant risks to infrastructure like oil pipelines. This study evaluates the efficacy of SH polymer materials in enhancing AFSD erosion resistance through three experimental approaches: film characterization, rainfall erosion simulation, and environmental compatibility assessment. Tensile tests demonstrated that SH polymer films (0.16–0.56 mm thick) retained >80% mass after prolonged immersion, exhibiting prolonged ductility (250 mm elongation) and stable post-immersion softening, ideal for enduring cyclic erosion. Rainfall simulations (200 mm/h intensity) revealed that SH application rates ≥ 1.5 kg/m² reduced soil loss by >90%, with 2.0 kg/m² ensuring near-complete slope integrity across planar/curved morphologies. Ecological tests confirmed SH’s environmental friendliness, as treated soils supported robust tall fescue growth without permeability inhibition. The findings advocate SH polymers as a sustainable solution for AFSD stabilization, combining mechanical resilience, terrain adaptability, and eco-compatibility. Full article

Tall fescue toxicosis negatively impacts blood flow, elevates body temperature, and reduces beef cattle’s average daily gain (ADG). In previous studies, isoflavones have diminished the symptoms of tall fescue toxicosis in ruminants. Therefore, this dataset determined the impact of low concentrations of isoflavone doses on animal vasculature, body temperature, ADG, and rumen microbial communities in beef cattle. A 21-day experiment with Angus cattle consisted of four isoflavone doses: 0 g, 2 g, 4 g, and 6 g, along with a control group. Isoflavones were mixed with 0.5 kg of dried distiller’s grains (DDGs). Daily individual rectal temperatures were recorded. Weekly blood serum was collected via coccygeal venipuncture, blood vasculature data were measured via color Doppler ultrasound, and body weight (BW) was recorded. Approximately 100 mL of rumen content was collected at the end of the trial. The pulsatility index (PI) decreased in the control group compared to the 2 g and 4 g groups (p = 0.01). Animals in the isoflavone treatment groups recorded a higher rectal temperature (p < 0.05). ADG was reduced in animals undergoing isoflavone treatments (p < 0.001). Finally, there was no impact on the rumen microbial communities (p > 0.05). Isoflavone supplementation may mitigate tall fescue toxicosis and improve animal performance at greater doses. Full article

Fescue toxicosis (FT) is a mycotoxin-related disease caused by the ingestion of tall fescue, naturally infected with the ergot alkaloid (EA)-producing endophyte Epichloë coenophiala. Some grazing on endophyte-free (E−) or non-toxic (NT), commercial endophyte-infected pastures takes place in the US as well. Earlier, we found that grazing on toxic fescue with low levels of EAs during fall affects thermoregulation, behavior, and weight gain. Building on these findings, the current study aimed to investigate how the presence of low EA-producing E+ or NT endophytes can influence animal metabolome, microbiome, and, ultimately, overall animal health. Eighteen Angus steers were placed on NT, E+, and E− fescue pastures for 28 days. Urine, rumen fluid (RF), rumen solid (RS), and feces were collected pre-exposure, and on days 2, 7, 14, 21, and 28. An untargeted high-resolution metabolomics approach was used to analyze urine and RF, while 16S rRNA-based next-generation sequencing (NGS) was used to examine RF, RS, feces, and fescue plant microbiomes. While alpha- or beta-microbiota diversity across all analyzed matrices were unaffected, there were specific effects of E+ on the relative abundance of some taxa (i.e., Prevotellaceae). Additionally, E+ grazing impacted aromatic amino acid metabolism in the urine and the metabolism of lipids in both the RF and urine. In both matrices, trace amine-related metabolic features differed markedly between E+ and the other groups. Compared to the endophyte-free group, endophyte presence, whether novel or toxic, influenced amino acid and carbohydrate metabolism, as well as unsaturated fatty acid biosynthesis. These findings suggest that low-EA-producing and non-toxic endophytes in fescue have more prominent effects on the metabolome than the microbiome, and this metabolome perturbation might be associated with decreased performance and reported physiological signs of FT. Full article

Tall fescue (Festuca arundinacea Schreb.) is a herbaceous species that is commonly used for ecological slope restoration in China. However, water scarcity often constrains its growth due to the unique site conditions of steep slopes and climate-induced drought stress. This study aims to compare the ameliorative effects of silicon nanoparticles (Si NPs) and cellulose nanocrystals (CNCs) on drought stress in tall fescue and to elucidate their underlying mechanisms of action. The results indicated that drought stress impaired photosynthesis, restricted nutrient absorption, and increased oxidative stress, ultimately reducing biomass. However, Si NPs and CNCs enhanced drought tolerance and promoted biomass accumulation by improving photosynthesis, osmotic regulation, and antioxidant defense mechanisms. Specifically, Si NP treatment increased biomass by 48.71% compared to drought-stressed control plants, while CNCs resulted in a 33.41% increase. Transcriptome sequencing further revealed that both nanomaterials enhanced drought tolerance by upregulating genes associated with photosynthesis and antioxidant defense. Additionally, Si NPs improved drought tolerance by stimulating root growth, enhancing nutrient uptake, and improving leaf structure. In contrast, CNCs play a distinct role by regulating the expression of genes related to cell wall synthesis and metabolism. These findings highlight the crucial roles of these two nanomaterials in plant stress protection and offer a sustainable strategy for the maintenance and management of slope vegetation. Full article

Incorporating temperate legumes is a strategy for increasing nitrogen (N) in tall fescue (Schedonorus arundinaceus (Schreb.) Dumort, nom. Cons) systems. However, when temperatures are elevated, biological N-fixation (BNF) by temperate legumes is limited. Sunn hemp (Crotalaria juncea L.), a warm-season annual legume, may provide greater N input during the warm season. This 2-year study aimed to (1) determine BNF in sunn hemp-tall fescue mixed pastures and (2) determine N transfer from sunn hemp to tall fescue. The experiment included four replicates of two treatments: tall fescue (TF) and tall fescue intercropped with sunn hemp (TF+SH), arranged in a randomized complete block design. Response variables included δ¹⁵N, N derived from the atmosphere (%NDFA), BNF, N concentration, N transferred (%Ntran), N stock, and herbage accumulation (HA). Herbage accumulation was 16% greater in TF+SH compared to TF (p < 0.05). Root mass was 43% greater for TF compared to both species combined in TF+SH (p < 0.05). Herbage N was 40% greater in sunn hemp shoots than tall fescue shoots in TF or TF+SH (p < 0.05). Sunn hemp root N was 34% greater than tall fescue (p < 0.05). NDFA by sunn hemp was 88% and 100% in 2017 and 2018, respectively. BNF by sunn hemp was greater (p < 0.05) in 2018 than in 2017 (53.8 and 44.3 kg ha⁻¹, respectively). The %Ntran from sunn hemp to tall fescue was 13 and 20% in 2017 and 2018, respectively. Interseeding sunn hemp into tall fescue pastures can provide an alternate N source to tall fescue-based forage-livestock systems, increasing herbage accumulation during the summer grazing season. Full article

Ergot alkaloids present in endophyte-infected tall fescue can cause a series of negative effects in exposed cattle. This study evaluated the effectiveness of molasses-based block supplements (MBSs) in alleviating vasoconstriction, which leads to reduced peripheral blood flow, heat stress, and impaired growth performance in cattle. A total of 100 crossbred steers were assigned to five treatment groups: a negative control with no tall fescue seed; a positive control with ergot-infected tall fescue seeds; and three MBS treatments, including a control block, a block containing menthol, and a block containing capsaicin. Blood flow was assessed through ultrasound imaging of the coccygeal artery, while thermal imaging was used to monitor body temperature regulation. Growth performance, feed intake, and blood biomarkers were also measured. Cattle consuming MBS had improved weight gain, greater arterial diameters, and enhanced thermoregulation compared to those without supplements. No significant differences were observed between the different MBS formulations. These results suggest that molasses-based block supplementation can help mitigate heat stress and poor growth performance associated with ergot alkaloid consumption, potentially providing a practical nutritional strategy for cattle producers managing cattle exposed to ergot alkaloids. Full article

Accurate estimation of herbage mass is crucial for managing pastoral livestock systems. The Normalized Difference Vegetation Index (NDVI) from Unmanned Aerial Vehicle (UAV) sensors shows promise for high-resolution estimations of pasture herbage mass, but it is still unknown how this method differs among forage species, seasons, and pasture management practices. A commercial sensor was calibrated to predict herbage mass using NDVI. Additionally, the effect of different forage species, days of regrowth, and nitrogen (N) status on the relationship between NDVI and herbage mass was evaluated. Two pastures of tall wheatgrass (Thinopyrum ponticum) and tall fescue (Festuca arundinacea), divided into 30 and 72 plots, respectively, were assessed during spring and autumn regrowth over two years in Balcarce, Argentina. Doses of 0, 50, and 100 kg N ha⁻¹ were applied to tall wheatgrass, and 0, 50, 100, 200, 400, and 600 kg N ha⁻¹ were applied to tall fescue to create variability in herbage mass and N status. Exponential regression models of herbage mass (y) fitted against NDVI (x) showed an average R² of 0.83 ± 0.04 and a mean absolute error of 170 ± 60 kg DM ha⁻¹. The relationship between NDVI and herbage mass differed (p ≤ 0.05) between species, seasons, and regrowth stage, but was not influenced by N status (p > 0.05). Results suggest that accurate predictions of herbage mass using NDVI measurements by an UAV require frequent model recalibrations to account for observed differences among forage species, days of regrowth, and years. Full article

Groundwater pollution negatively impacts aquatic ecosystems and human health. On the other hand, conservation practices can help reduce groundwater and surface water pollution. Baseflow from agricultural fields can be an important source of nitrate-nitrite (NN) loads in lakes and other surface water bodies. Riparian agroforestry buffers can be an effective barrier between groundwater NN and surface water bodies. The study aimed to determine the effects of agroforestry buffers and widths on groundwater nitrate-nitrite (NN) exports from an agricultural grazing area into a farm lake using flow and solute transport models. The flow and solute models were calibrated and validated for the weather and land use (grazing) conditions observed during the monitoring period, and these conditions were repeated throughout the 10-year projection. The calibration and validation of the flow and solute transport models were satisfactory, yielding determination coefficients R² > 0.95 and Nash-Sutcliffe coefficients > 0.94. The area of study was modeled under four scenarios: tree-only buffers [cottonwood (Populus deltoides Bortr. ex Marsh.)]; grass-only buffers ([Tall fescue Schedonorus phoenix (Scop.) Holub, Red clover (Trifolium pretense L.), and Lespedeza (Lespedeza Michx)]); tree + grass buffers (a combination of the same tree and grass species of the other two scenarios; and a no-buffer scenario. The tree-only, grass-only, and tree + grass buffers reduced the total mass of NN discharged from the study unit to the lake by 98%, 97%, and 99%, respectively, compared to the no-buffer scenario. Doubling the buffer width from 15 m to 30 m decreased the NN discharge to the lake by 16-fold. Moreover, 7.5 m wide buffers had up to nine times greater NN discharge than 15 m buffers. Results show that agroforestry buffers with trees and grasses in riparian areas significantly remove NN exports in groundwater from agricultural fields, protecting the environment and human health. Full article

The aim of this experiment was to investigate the differences in the uptake and accumulation of rare earth elements (REEs) between selected plant species and the substrates used (soil with increased REE content, ash, and smelter waste). Eight plant species were included in the study: common yarrow (Achillea millefolium), false mayweed (Triplerosperum maritimum), tall fescue (Festuca arundinacea), marigold (Tagetes sp.), maize (Zea mays), white mustard (Sinapis alba), red clover (Trifolium pratense L.), and autumn fern (Dryopteris erythrosora). The study focused on the following REE representatives: lanthanum (La), cerium (Ce), europium (Eu), and gadolinium (Gd). Plant samples, divided into roots and shoots, were analyzed by ICP-MS. The obtained REE concentrations in plant tissues ranged from 9 to 697 µg kg⁻¹ (La), 10 to 1518 µg kg⁻¹ (Ce), 9 to 69 µg kg⁻¹ (Eu), and 9 to 189 µg kg⁻¹ (Gd). To determine the ability of plants to phytoextract REE, two factors were calculated: the translocation factor (TF) and the bioconcentration factor (BCF). The highest TF value was obtained for D. erythrosora growing on a substrate consisting of soil with increased REE content (Gd, TF = 4.03). Additionally, TF > 1 was obtained for all REEs in T. pratense L. In the experiment, the BCF was lower than 1 for all the plants tested. The study provided insight into the varying ability of plants to accumulate REEs, depending on both the plant species and the chemical properties of the substrate. Full article

Adequate but not excessive dietary energy supply is crucial for growth and productivity in cattle. This study aimed to evaluate the effects of three incremental changes in metabolizable energy (ME) levels in concentrate mixes, i.e., low (LEC, 10.4 MJ/kg DM), medium (MEC, 10.8 MJ/kg DM), and high (HEC, 11.0 MJ/kg DM), on growth performance and comprehensive physiological parameters in Hanwoo steers. Thirty steers, averaging 499 ± 38.0 kg, were randomly allocated to one of the treatments. Each steer received up to 8 kg of concentrate mix, with ad libitum access to tall fescue. Body weights were measured every four weeks. In week 12, rumen samples were collected, followed by fecal and blood samples. The HEC group exhibited a 16.5% higher average daily gain compared to the other groups (p = 0.035). Forage and total dry matter (DMI) were 46% and 12% lower in the HEC group (p < 0.001). Fiber digestibility increased with energy content (p < 0.05). Total volatile fatty acid and the acetate-to-propionate ratio decreased in the HEC group (p < 0.001), while blood creatinine concentration increased (p < 0.01). In conclusion, feeding Hanwoo steers with a high-energy concentrate mix (up to 11.0 MJ ME/kg DM) improved growth and feed efficiency without compromising rumen health. Full article

Condensed tannins (CTs) in certain leguminous forages can mitigate toxic alkaloid absorption linked to fescue toxicosis due to their high affinity towards various steroidal and protein-like alkaloids. However, their use as feed supplements remains underexplored. This study evaluated the impact of CT-rich sericea lespedeza (Lespedeza cuneata) pellets on the post-ingestive effects of fescue toxicosis. Twelve steers on wild-type endophyte-infected tall fescue pastures received either sericea lespedeza pellets (LES) or LES with polyethylene glycol (LPEG; negative control) for 12 weeks over three consecutive summers. Body weight, hair coat scores, temperatures (rectal and extremity), cortisol levels, and caudal artery lumen area were measured every four weeks. Steers fed LES showed trends toward higher ADG (p = 0.0999) and reduced hair retention (p = 0.0547) compared to those fed LPEG. Steers on LES also showed hotter tail skin temperatures (p = 0.0053) and cooler rectal temperatures (p < 0.0001) compared to those fed LPEG. LES-fed steers had a 21% larger caudal artery lumen area (p < 0.01), suggesting reduced vasoconstriction. Additionally, LES-fed steers tended to have lower hair cortisol (p = 0.0746), indicating reduced chronic stress. These results suggest that supplementation with CTs may alleviate the post-ingestive effects of fescue toxicosis, potentially by improving blood flow and reducing stress. However, further research is needed to determine whether CTs directly reduce alkaloid absorption, as well as to validate the long-term efficacy of CT supplementation. Full article

γ-Aminobutyric acid (GABA), an endogenous amino acid widely found in living organisms, has important functions in plants such as regulating growth and development, maintaining carbon and nitrogen nutrient balance, and coping with adversity. In this study, we investigated the effects of exogenous 0.5 mmol/L GABA on the growth, antioxidant metabolism, and GABA shunt metabolism of tall fescue under 20 μmol/L Cd stress, using tall fescue (Festuca arundinacea) ‘Ruby II’ under hydroponics conditions. The results showed that (1) applying GABA for 3, 7, 11, and 15 d under Cd stress inhibited Cd transport from roots to leaves and promoted plant height, alleviating the effects of Cd stress on plant growth. (2) Exogenous 0.5 mmol/L GABA had an interesting regulatory effect on the activation of the antioxidant enzyme system induced by stress at different stages, which was accompanied by a decrease in malondialdehyde (MDA) contents and alleviated the degree of cell membrane lipid peroxidation under cadmium stress. Specifically, peroxidase (POD) enzyme activity reactions initially responded on the 3rd and 7th days of stress, and the changes in catalase (CAT) enzyme activities concentrated on the 11th and 15th days of the later stage. Ascorbate peroxidase (APX) enzyme was active throughout the whole stress period in the roots. Multiple factorial analyses further proved that the antioxidant pathway strongly influenced the survival and growth of tall fescue under stress in the presence of GABA. (3) Application of exogenous GABA activated the branching pathway for GABA synthesis from Glu decarboxylation (GABA shunt) with a higher contribution in the leaves, which induced changes in glutamate content, and plants maintained a higher endogenous GABA content and signal to regulate the plant antioxidant system and reduce cell membrane damage, thus improving the tolerance of plants to Cd stress. Full article

This study compared the profitability when feeding silages of different grass species in enterprises with either dairy cows, beef breed bulls, or beef suckler cows. Traditional (TR) grasses timothy and meadow fescue was compared to the alternative wet-and-drought-resistant (WD) grasses tall fescue, festulolium, and reed canary grass in three different weather scenarios with either normal conditions (Ref), delayed late harvest time due to wet weather conditions (Wet), or decreased grass yield due to dry weather conditions (Dry). Contribution margin calculation was conducted for three geographical regions in Sweden. In the Ref and Wet scenarios, TR was more competitive than WD for dairy cows and beef bulls in all regions. Also in the Dry scenario, TR was more competitive than WD for dairy cows, as the lower production cost of the WD was outweighed by a lower milk yield of cows fed WD compared to cows fed TR. Contrary, for beef bulls, WD gave a higher contribution margin than TR did in the Dry scenario, where the break-even for WD being superior over TR occurred when more than every second year was dry. WD reed canary grass was always more competitive than TR and WD festulolium for beef cows. Full article