Hemp Biomass Research Articles

Industrial hemp biomass negatively affected by herbicide drift from corn and soybean herbicides.

The establishment of industrial hemp (Cannabis sativa L.) fields near row crops has raised concerns about the potential adverse effects of herbicide drift on hemp production. This study examined hemp susceptibility to drift of herbicides registered for use in corn and/or soybeans. Herbicide solutions (2,4-D, dicamba, glufosinate, glyphosate, imazethapyr, lactofen, mesotrione) were applied separately in the wind tunnel (3.6m s-1 airspeed), simulating drift scenarios, with conventional TP95015EVS (TP) and air inclusion AI95015EVS (AI) flat fan nozzles calibrated to deliver 140L ha-1 carrier volume at 230kPa. Mylar cards and hemp plants (20-25cm tall) were placed downwind up to 12m. Spray deposition from mylar cards was quantified using fluorometry and hemp biomass was collected 21 post application. Results indicated the nozzle design influenced downwind deposition; 5% of spray deposits from the TP nozzle reached 5.9 m downwind versus 2.0 m for the AI nozzle. Glyphosate, glufosinate, and mesotrione caused the highest biomass reductions, with 50% reductions observed at 19.3 (inferred), 8.7, and 9.3m downwind for TP nozzle, and 4.1, 4.0, and 2.9m for AI nozzle. These findings suggest herbicide applications at airspeeds of 3.6m s-1 or greater present a risk to nearby hemp fields.

Review of hemp components as functional feed and food ingredients: impact on animal product quality traits and nutritional value

This review examined the potential of hemp components as functional feed and food ingredients, focusing on their impact on the quality and nutritional value of animal products. Following hemp legalization, there was growing interest in its potential to enhance animal diets and processed animal products due to its rich nutritional profile, including high levels of polyunsaturated fatty acids (PUFA), essential amino acids, and fibre. Incorporating hemp components into feed for monogastric animals, particularly poultry, improved lipid stability, sensory attributes, and the fatty acid composition of meat and eggs. Hemp supplementation for ruminants, especially in goats, increased PUFA and conjugated linoleic acid (CLA) content in milk, improved meat tenderness, and enhanced oxidative stability. However, research on hemp supplementation for pigs and beef remained limited, indicating the need for further exploration of these species. Hemp cake, rich in protein, fibre, and essential fatty acids, was the most widely used hemp component due to its economic viability, nutritional benefits, and sustainability, contributing to improved meat and milk quality. Regulatory concerns about the transfer of tetrahydrocannabinol (THC) residues in the produced animal products restricted the use of hemp biomass. In processed animal products, hemp components were studied for their potential to enhance nutritional value, replace animal fats, and serve as natural preservatives. Although they improved the fatty acid profile and antioxidant properties of meat products, challenges such as textural changes and increased lipid oxidation needed to be addressed for optimal use. Limited studies on dairy products indicated promising nutritional enhancements, but textural issues could impact consumer acceptance. In conclusion, hemp components show significant potential for improving the quality and nutritional value of animal products. Further research is necessary to address regulatory, sensory, and formulation challenges and to expand their application across different animal species and processed animal products.

Pyrolysis of industrial hemp biomass from contaminated soil phytoremediation: kinetics, modelling transport phenomena and biochar-based metal reduction

Phytoremediation is the use of vegetation for the in situ treatment of contaminated environments. After plants have been used for phytoremediation of soils, their biomass can be used for example as value-added products or converted by thermochemical processes. Large-scale application of pyrolysis technology for phytoremediation biomass requires accurate predictive kinetic models and a characterization of the toxicity of the materials produced. The pyrolysis of industrial hemp (Cannabis sativa L.) was investigated on a laboratory scale by varying the process conditions and accurately modelled by considering four pseudo-components with first reaction order. The average value of the coefficients of determination is 0.9980. Biomass and biochar were characterized and the main components of the gas phase were monitored. We found Cd, Pb, and Zn in the roots, although in lower amounts than in the soil. Especially the leaves and stems showed negligible traces of these elements, so that these parts can be used directly, even if the hemp was grown on the polluted soil. After pyrolysis, the concentration of pollutants in the solid fraction decreased, which could be attributed to the reduction of metal oxides (or salts) to elemental form and subsequent evaporation. This pyrolysis process has the potential to treat heavy metal-rich biomass, with gas phase purification via condensation, yielding agricultural-grade biochar, CO-rich gas and a highly concentrated heavy metal stream in absorbent material.

Enhancing biogas production from hemp biomass residue through hydrothermal pretreatment and co-digestion with cow manure: Insights into methane yield, microbial communities, and metabolic pathways

This study investigates the enhancement of biogas production from hemp biomass residue (HBR) through hydrothermal pretreatment and co-digestion with cow manure (CM). Hydrothermal pretreatment at 200 °C for 15 min significantly improved the methane yield from 311.5 to 434.3 mL-CH4/g-VSadded (p ≤ 0.05) from HBR at 10% total solids (TS) loading, a 39% increase. Co-digestion with CM at an optimum ratio of 80:20 further increased the methane yield (738.7 mL-CH4/g-VSadded), representing a 70% improvement over pretreated HBR alone and a 137% increase compared to untreated HBR. Microbial community analysis revealed the dominance of Methanosaeta, comprising 83–93% of archaeal genera across samples. Gene expression analysis showed acetoclastic methanogenesis as the dominant pathway, accounting for 80% of methanogenesis sequences. Hydrogenotrophic methanogenesis and CO2 reduction with H2 pathways contributed 10% each. The optimized process achieved a biodegradation efficiency of 94% for hydrothermally pretreated HBR, compared to 68% for untreated HBR. Mass balance analysis demonstrated that combining hydrothermal pretreatment with anaerobic digestion increased biogas yield from 79% for untreated HBR to 86% for pre-treated HBR (PHBR) co-digested with CM. Integrating hydrothermal pretreatment and co-digestion enhances biogas production from lignocellulosic agricultural residues, contributing to sustainable waste management and renewable energy production.

430 Spent hemp biomass increases bone mineral density in broilers

Abstract Spent hemp biomass (SHB) is a byproduct of CBD oil production, which has been used in multiple trials recently as an alternative feed for livestock, but it has not been approved as a feed ingredient by the FDA-CVM. This is due in part to the lack of information on the potential effects on animal health. Recent studies have shown possible effects of cannabinoids on bone healing, though the effects on bone growth and calcification are not well established. The objective of the study was to investigate the effects of varying levels of SHB on bone growth, calcification, and strength. A total of two hundred birds (5-d-old Cobb 500 Cornish Cross chicks) were randomly assigned to five different rooms with 4 pens per room and 10 animals/pen. Birds received isonitrogenous, isocaloric diets with either 0, 5, 10, or 20% SHB until euthanasia at 42 d. The tibiotarsus, femur, and humerus were collected from 2 males and 2 females per pen for 80 birds (20 per treatment group). The tibiotarsus bending strength was measured with an Instron 5969 using a three-point bending testing fixture set at 10 mm/min for 19 parameters of the bending and breaking properties. The humerus and femur were scanned with a Hologic Discovery A (S/N 84870) DEXA for mineral content (BMC) and density (BMD). Statistical significance was set at P ≤ 0.05 and analyzed using a generalized linear mixed model. BMD and BMC were not affected by treatments in the humerus, a pneumatic bone, but in the weight bearing femur bones, a significant effect on both BMD (P = 0.0078) and BMC (P = 0.0069) was observed. The change in BMC was quadratic, with a peak in animals receiving 10% SHB in the diet, but the BMD effect was linear with the increased dose of SHB in the diet. In the tibiotarsus three-point bending analysis, no significant changes were found in any of the strength and bending parameters measured, except a tendency (P = 0.07) for a greater work-to-fracture adjusted by bone diameter in 5% vs. 0% SHB group. These data indicate some interaction of SHB on the mineralization of bone; however, the level causes less than significant changes to the overall strength of the bone.

Feeding spent hemp biomass does not adversely affect fertility in rams.

To determine the reproductive effects of feeding spent hemp biomass (SHB) to rams. Several studies suggest cannabidiols negatively affect reproductive characteristics, and the reproductive effects of SHB ingestion have not been investigated in any species. Spent hemp biomass is high in protein and essential fatty acids, indicating a potential use in livestock diets pending studies investigating its safety in animals. Polypay rams approximately 6 months old were randomly assigned to 5 feeding trial groups (n = 7/group): either a low or high concentration of SHB in diet for either 4 or 8 weeks plus a control group. Blood samples were collected for hormone assays. At the conclusion of the feeding trial, the testes were removed, and sperm collected directly from the vas deferens were evaluated for motility (total, progressive, and speed), morphology, and concentration. A section from each ram's testes was formalin fixed, paraffin embedded, and subjected to routine immunohistochemistry to determine the expression of fertility-associated proteins deleted in azoospermia-like and Boule, followed by quantitative image analysis. Rams fed either 10% or 20% SHB for 8 weeks had significantly higher progressive sperm motility compared to controls. There were no significant differences between the treatment and control groups in the other parameters studied. Boule immunoexpression was adversely affected, whereas deleted in azoospermia-like immunoexpression was differentially affected by SHB ingestion. We conclude that up to 20% of the diet can be fed as SHB to rams for 8 weeks without adversely affecting testicular or sperm function. Supplementing young rams with SHB is unlikely to affect fertility.

Liver Transcriptomic Profiles of Ruminant Species Fed Spent Hemp Biomass Containing Cannabinoids.

The inclusion of spent hemp biomass (SHB), an extracted byproduct from industrial cannabidiol (CBD) production, in the diets of dairy cows and lambs appears to be safe with minor effects on the metabolism, including a decrease in circulating cholesterol and increase bilirubinemia, both associated with liver metabolism. Those effects could be consequence of the presence of cannabinoids, particularly Δ9-tetrahydrocannabinol (THC) and CBD in the SHB. This study aimed to study the transcriptional profile of the liver of dairy cows and lambs fed SHB. Dairy cows received SHB or alfalfa pellet for four weeks of intervention (IP) and four weeks of withdrawal periods (WP). Finishing lambs were fed a control diet (CON), 10% (LH2), or 20% (HH2) SHB for 2 months or 1 month followed by 1-month SHB withdrawal (LH1 and HH1, respectively). RNA sequencing was performed, and the mRNA was annotated using the latest reference genomes. The RNAseq data were filtered, normalized for library size and composition, and statistically analyzed by DESeq2. The bioinformatic analysis was performed by using DAVID, Gene Set Enrichment Analysis (GSEA), and the Dynamic Impact Approach. Using a 0.2 FDR cut-off, we identified only ≤24 differentially expressed genes (DEG) in the liver by feeding SHB in dairy cows and a larger number of DEGs in lambs (from 71 in HH1 vs. CON to 552 in LH1 vs. CON). The KEGG analysis demonstrated that feeding SHB in dairy cows and lambs had relatively minor to moderate metabolic alterations in dairy cows and lambs mainly associated with amino acids and lipid metabolism whereas cholesterol synthesis was overall activated in lambs. GSEA identified activation of the PPAR signaling pathway only in dairy cows. We found an opposite effect on activation of metabolism of drug and xenobiotics by cytochrome P450 enzymes in dairy cows and lambs receiving less SHB but an inhibition in HH2 lambs. Immune system-related pathways were inhibited by feeding SHB in lambs, but the impact was minor. Cumulatively, inclusion of SHB containing cannabinoids in dairy and lambs demonstrate very little effects on the alteration of transcriptomic profile of the liver.

Polymers from renewable resources: Glucose from enzymatic hydrolysis of hemp biomass

Polymers from renewable resources: Glucose from enzymatic hydrolysis of hemp biomass

Cannabinoid residuals in tissues of lambs fed spent hemp biomass and consumer's exposure assessment

Spent hemp biomass (SHB) contains trace amounts of cannabinoids, including Δ9-tetrahydrocannabinol (Δ9-THC), that may accumulate in the tissues of animals consuming SHB. We measured cannabinoid residues in the liver, adipose tissue, and muscle of finishing lambs fed either 10% or 20% SHB for 8 weeks, or 4 weeks followed by 4 weeks SHB withdrawal. We detected multiple cannabinoids in the liver at a similar proportion to the SHB. However, CBD and Δ9-THC were enriched >20-fold in the adipose and muscle, compared to their proportion in SHB. The highest concentration of Δ9-THC was detected in adipose tissue and was 7.4-times higher than in muscle. Most cannabinoids were undetectable in tissues after 4 weeks of clearance. The consumers’ exposure assessment on Δ9-THC revealed tissue levels of total THC (THCA+Δ9-THC) that exceed the acute reference dose of 1 μg/kg BW across population groups. When consuming meat from the lambs fed 10% and 20% SHB, the maximum total THC exposure was 2.03 and 7.32 μg/kg BW, respectively, equal to or below the Lowest Observed Adverse Effect Level of 36 μg/kg BW, the No Observed Adverse Effect Level of 12 μg/kg BW or a tolerable dose intake of 7 μg/kg BW.

Relay-cropping enhances the availability of low iLUC risk lignocellulosic feedstock for advanced biofuels

The relay-cropping (R) of a winter cereal and a high biomass yielding legume for advanced biofuel production can enlarge the legume growing season, thus increase its biomass yield and synchronize nitrogen (N2)-fixation capacity to uptake. The aim of the present study was to evaluate the biomass and food yield of two sunn hemp (Crotalaria juncea L.; cv. Ecofix) – wheat (Triticum aestivum L.; cv. Bologna) relay-cropping systems compared to double-cropping, in order to explore the impact on grain and biomass yield of the variable crops overlapping periods. The evaluated relay-cropping systems foreseen an early November wheat sowing into no till bare soil with: i) sunn hemp harvested at full flowering (beginning of November, R1) and ii) sunn hemp harvested at the end of flowering (end of November, R2). In the control (C) double-cropping, sunn hemp was harvested at the beginning of flowering (end of September). Quantitative and qualitative parameters were evaluated for each system across two growing seasons (2019–20 and 2021–22). Sunn hemp biomass and wheat straw residues were determined. The grain qualitative parameters determined for wheat were: grain volume weight (VW), crude protein, wet gluten, starch and Zeleny index (ZI). The R1 and R2 sunn hemp-wheat relay-cropping biomass yield (12.5 Mg d.m. ha−1 y−1) was similar to C (11.3 Mg d.m. ha−1 y−1). In 2019–20, environmental conditions were more favorable, thus, yields were higher than in 2021–22 by 72 %. Wheat grain yields in 2021–22 were higher in R1 (2.9 Mg d.m. ha−1) than C (2.0 Mg d.m. ha−1), with R2 showing intermediate values. In 2019–20, however, the grain quality was higher in R1 than in C for crude protein (+11 %), wet gluten (+15 %), and ZI (+26 %) eventually due to an increased N2-fixation by sunn hemp that reached full flowering. The local availability of low iLUC risk lignocellulosic feedstock for advanced biofuel could be increased through crop intensification with relay-cropping, showing the potential to provide additional biomass and enhance food quality thus complying with the additionality measures set out by the Delegated Regulation of REDIII.

Valorisation of industrial hemp (Cannabis sativa L.) residues and cheese whey into volatile fatty acids for single cell protein production

The production of single cell protein (SCP) using lignocellulosic materials stands out as a promising route in the circular bioeconomy transition. However, multiple steps are necessary for lignocellulosics-to-SCP processes, involving chemical pretreatments and specific aerobic cultures. Whereas there are no studies that investigated the SCP production from lignocellulosics by using only biological processes and microbial biomass able to work both anaerobically and aerobically. In this view, the valorisation of industrial hemp (Cannabis sativa L.) biomass residues (HBRs), specifically hurds and a mix of leaves and inflorescences, combined with cheese whey (CW) was investigated through a semi-continuous acidogenic co-fermentation process (co-AF). The aim of this study was to maximise HBRs conversion into VFAs to be further used as carbon-rich substrates for SCP production. Different process conditions were tested by either removing CW or increasing the amount of HBRs in terms of VS (i.e., two and four times) to evaluate the performance of the co-AF process. Increasing HBRs resulted in a proportional increase in VFA production up to 3115 mg HAc L−1, with experimental production nearly 40% higher than theoretical predictions. The synergy between HBRs and CW was demonstrated, proving the latter as essential to improve the biodegradability of the former. The produced VFAs were subsequently tested as substrates for SCP synthesis in batch aerobic tests. A biomass concentration of 2.43 g TSS L−1 was achieved with a C/N ratio of 5.0 and a pH of 9.0 after two days of aerobic fermentation, reaching a protein content of 42% (g protein per g TSS). These results demonstrate the overall feasibility of the VFA-mediated HBR-to-SCP valorisation process.

One pot synthesis of furan-modified lignin from agricultural waste via lignin-first approach

This study investigated a lignin-first approach to produce furan-modified lignin from sugarcane bagasse (SB), rice hull (RH), and sunn hemp biomass (SHB) using 5 methylfurfural (MF) and 5 methul-2-furanmethanol (MFM). The reaction time (5 h) was selected based on the delignification of SB using methanol and Ru/C catalyst which yielded the highest hydroxyl content. Delignification of SB with various MF weight ratios (1:1, 1:2, 1:3, 2:1, and 3:1) revealed that 1:1 and 2:1 ratios produced the highest hydroxyl content (7.7 mmol/g) and bio-oil yield (23.2 % wt% total weight). Further exploration identified that RH and MF at 1:1 ratio and SHB and MF at a 2:1 ratio produced the highest hydroxyl content (13.0 mmol/g) and bio-oil yield (31.6 % wt% tot. weight). This study developed a one-step method to extract and modify lignin with furan compounds simultaneously while opening new avenues for developing value-added products.

Utilizing sustainable hemp biomass as an eco-friendly for potentially toxic elements removal from water

Potentially toxic elements in water is one of the important environmental problems. In this study, it was aimed to produce an environmentally friendly and cost-effective biosorbent using sustainable hemp biomass. The chemical composition of hemp biosorbents was characterized by FTIR, SEM, and XRD, and the results showed that the biosorbent could be a good alternative. A batch system was used to investigate the effects of initial concentration, pH, contact time, and temperature on the removal performance of Cu (II) and Zn (II) ions. The statistical analysis was performed, and the amount of adsorbed substance, kinetic values, and experiment results were evaluated for suitability. Kinetic data determined the best fit to pseudo-second-order kinetics for Cu (II) and Zn (II) ions. Adsorption determined the Langmuir model for Cu (II) ions and the Freundlich model for Zn (II) ions. The maximum adsorption capacity in the batch system was determined as 25.59 mg/g for Cu (II) and 12.97 mg/g for Zn (II) ions. The obtained thermodynamic data confirmed the endothermic nature of the adsorption. In desorption studies, after three cycles, the adsorption efficiency decreased from 83.3% to 52.8% for Cu (II) and from 82.1% to 49.7% for Zn (II). Study results showed that hemp biosorbent may be an alternative adsorbent that can be used to remove PTEs from wastewater.

Impact of soil-residual herbicides on industrial hemp (Cannabis sativa) phytotoxicity and biomass yield in west Texas

Abstract Industrial hemp is a multipurpose crop cultivated for fiber, seed, human food, and animal feed. Hemp legalization in Texas creates a considerable potential to increase its acreage in semi-arid conditions; however, knowledge is limited on growing hemp optimally in Texas. Best management practices, including weed control, require evaluation for profitable hemp production. As little is known about the herbicide tolerance of hemp, field studies were conducted to test several soil-residual herbicides with different modes of action for phytotoxicity to two hemp cultivars, ‘Yuma’ and ‘Jinma’. The experimental units were randomized three times in a blocked split-plot design with hemp cultivars in the main plots and soil-residual herbicides in the subplots. Ethalfluralin, the mixture of sulfentrazone and S-metolachlor, prometryn, and S-metolachlor, resulted in 60% to 90% and 73% to 100% weed control as compared to the nontreated control in 2021 and 2022, respectively. The highest hemp germination, stand count, and plant height were observed with ethalfluralin and S-metolachlor herbicides; however, no significant differences were observed for hemp germination and plant height compared to the nontreated control. S-metolachlor, ethalfluralin, fomesafen, and prometryn resulted in similar hemp biomass compared to the nontreated control. Overall, the results indicate that hemp is tolerant to ethalfluralin, prometryn, and S-metolachlor, and these soil-residual herbicides were effective for weed control in hemp. The mixture of bicyclopyrone plus S-metolachlor, metribuzin plus S-metolachlor, and mesotrione should be avoided, as they caused significant injury to hemp plants. Future research is needed to test the efficacy of different preemergence and postemergence herbicides that can be used in industrial hemp grown under different environments, making sure the delta-9-tetrahydrocannabinol content of the hemp is below the legal content restrictions.

Cellulose- supported sulfated-magnetic biocomposite produced from hemp biomass: Effective removal of cationic dyes from aqueous solution

In present study, eco-friendly sulfated cellulose-magnetic biocomposite was successfully synthesized with a simple method from hemp biomass. ATR-FTIR was used to determine chemical changes, while FE-SEM-EDS, STEM, XRD, TG/DTA, and BET techniques were employed to identify changes in morphology, elemental composition, crystal structure, and thermal degradation. Moreover, the saturation magnetization and pHpzc values of the MSHB were also determined. The effectiveness of magnetic sulfated hemp biomass (MSHB) was tested in the removal of cationic dyes from wastewater, including methylene blue (MB), crystal violet (CV), and malachite green oxalate (MGO). The adsorption all three dyes to MSHB, the pseudo-second-order kinetic model and the Langmuir model were determined to be more appropriate, and was endothermic and spontaneous from thermodynamic parameters, too. The maximum MSHB adsorption capacities were found to be 457.6, 509.3, and 1300 mg/g for MB, CV, and MGO at 298 K. With increasing temperature, it also drastically increased in capacity. The outstanding property of the MSHB is that it shows high removal performance wide pH range, even after ten cycles its high removal efficiency is still over 96 % for all three dyes and almost unaffected from dense matrix medium. These results demonstrate that MSHB is remarkable adsorbent for removing cationic dyes.

Novel hemp biomass-derived activated carbon as cathode material for aqueous zinc-ion hybrid supercapacitors: Synthesis, characterization, and electrochemical performance

This research paper investigates the use of aqueous electrolytes in multivalent zinc-ion hybrid supercapacitors, highlighting their advantages over traditional supercapacitors in terms of increased energy density, cost-effectiveness, and enhanced safety. The study focuses on synthesizing activated carbon materials from hemp biomass through hydrothermal synthesis and KOH chemical activation. The resulting activated carbon possesses a highly porous structure essential for efficient energy storage. Herein, various advanced techniques were employed to examine the structural properties of the activated carbon material, such as X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Thermogravimetric analysis (TGA), Brunauer-Emmett-Teller (BET) analysis, Fourier-Transform Infrared (FTIR) spectroscopy, Energy-Dispersive X-ray spectroscopy (EDS), and X-ray Photoelectron Spectroscopy (XPS). On the other flip side, the hemp-derived carbon cathode exhibits a high electrochemical capacity of 220 F/g and an energy density of 65 Wh/kg, highlighting its potential for efficient energy storage. Moreover, the cathode material demonstrates remarkable cycling stability, retaining over 98 % of its capacity after 2000 charge/discharge cycles, indicating a promising long cycle life. Overall, this study emphasizes the potential of aqueous electrolytes and hemp biomass-derived carbon materials in advancing the development of high-performance multivalent zinc-ion hybrid supercapacitors.

Influence of Sunn Hemp Biomass Incorporation on Organic Strawberry Production

Sunn hemp (Crotalaria juncea L.), a warm season leguminous cover crop, is commonly used in rotation with organic strawberry production in Florida’s subtropical environment. This study was conducted to explore the impacts of sunn hemp on growth and yield performance of the subsequent organic strawberry crop in sandy soils, taking into consideration the nutrient contribution from soil incorporation of sunn hemp biomass. Sunn hemp was seeded during the summer off-season and terminated before flowering, three weeks prior to the fall planting of two strawberry cultivars (‘Strawberry Festival’ and ‘Camino Real’). With sunn hemp residues incorporated into the soil, two application rates of nitrogen (N) through pre-plant organic fertilization for the strawberry season were used, including N at a rate of 84 kg/ha, without consideration of the N credit from sunn hemp, and N at a rate of 19.8 kg/ha, with consideration of the estimated N credit from sunn hemp. A summer fallow without cover crop and with a pre-plant organic fertilizer application at the N rate of 84 kg/ha was included as the control. Overall, the sunn hemp incorporation at three weeks after termination did not benefit the strawberry plant growth or fruit yield in this study, with rather low levels of soilborne pathogen and nematode infestations. Both sunn hemp treatments exhibited a significantly lower level of total soil N compared to the summer fallow plots at the end of the strawberry season. The reduction in the pre-plant N fertilization resulted in lower above-ground plant dry weight and accumulation of N, phosphorus (P), and potassium (K) at the end of the strawberry season, along with fewer leaves and smaller crowns of the strawberry plants during the early season. Both sunn hemp treatments decreased early fruit yields, while the sunn hemp treatment with the reduced N fertilization also led to a significant reduction in the total fruit number and weight, although no significant differences in the whole-season marketable fruit yield were observed among the nutrient management treatments. Overall, ‘Strawberry Festival’ yielded higher than ‘Camino Real’, but the effects of nutrient management did not vary with the strawberry cultivars. Further studies are needed to enhance organic strawberry nutrient management involving rotational cover crops.

PSIII-1 Effect of Cannabidiol Extraction on the Cell Wall Carbohydrate Composition of Hemp Inflorescences

Abstract Since the 2018 Farm Bill, US growers have been allowed to cultivate hemp (Cannabis sativa L.), prompting interest in exploring the use of hemp products in ruminant diets. Extraction of cannabidiol (CBD) oil from hemp biomass generates spent inflorescent material that could be upcycled as a feedstuff, yet little is known about its fiber composition. A recent study measured in vitro true digestibility and fermentation parameters of multiple hemp cultivars, some intact and some CBD-extracted (Altman et al., 2022). Both categories of hemp inflorescence material had similar or greater total digestible nutrients (TDN) than an alfalfa cube control, supporting hemp’s potential as a feedstuff. However, comparisons between non-extracted and CBD-extracted samples could not be made, and the fiber content was only described as neutral detergent fiber (NDF). Fiber composition can significantly impact ruminal digestibility, and in-depth characterizations of cell wall carbohydrate composition can provide further insight into the digestibility of a specific plant-based feed. Therefore, in the present study, we examined the effect of CBD oil extraction on the cell wall carbohydrate composition of the inflorescent material of two hemp cultivars. Intact (Biomass) and CBD-extracted (Spent) inflorescent material from two hemp cultivars, Mary and Zelios, were analyzed. The scell wall monosaccharides of the samples were released via two complementary acid hydrolyses, methanolysis and Saeman (sulfuric acid) hydrolysis, and separated and quantified using high-performance anion-exchange chromatography coupled with pulsed amperometric detection (HPAEC-PAD). Additionally, the carbohydrate linkage patterns were assessed by generating partially methylated alditol acetates (PMAAs). Student’s unpaired t-tests were run in GraphPad Prism, and no differences (P > 0.05) in monosaccharide concentrations based upon treatment (CBD extraction) or cultivar were found with either hydrolysis method except for the methanolysis glucose concentration between the biomass forms of the two cultivars where Mary Biomass possessed more glucose than Zelios Biomass (P <b0.001). In the Saeman hydrolysates, glucose was the dominant monosaccharide (38.75 ± 1.44 molar %), indicating a large amount of cellulose, supported by the presence of 1,4-Glcp in the linkage analysis. Linkage analysis also revealed the presence of xyloglucans and rhamnogalacturonan Type 1 pectins in all materials. The data showed no effect of CBD oil extraction on the monosaccharide composition, suggesting that the extraction process leaves the fiber components mostly intact, but there may be differences in glucose concentration (and consequently cellulose content) between cultivars of hemp. Future studies may benefit more from investigating the impact of hemp cultivar on fiber digestibility rather than impact of the CBD extraction process.

Optimizing the planting time and stand density of sunn hemp intercropping for biomass productivity and competitiveness in a maize-based system

ContextOptimizing cover crop intercropping should aim to be sustainable, economically feasible and environmentally benign. Significant consideration must be given to cover crop plant timing and stand density adjustments to complement the resource demands of the dominant crop, while ensuring optimal biomass yields. ObjectiveThe study assessed a range of intercropping indices to evaluate the influence of different planting times and stand densities of sunn hemp (Crotalaria juncea L.) when intercropped with maize (Zea mays L.). The evaluation focused on interspecies interactions in relation to aboveground biomass production. MethodsA split-plot experiment was conducted using the in-field rainwater harvesting (IRWH) technique. The main plot factors included three intercropping times: simultaneous with maize planting, at the V15 and the R1 maize growth stages. The subplot factors consisted of three stand densities (16, 32 and 48 plants m−2), with three replicates for both the 2019/20 and 2020/21 seasons. Intercropping indices, including land equivalent ratio and coefficient, area time equivalent ratio, land use efficiency, system productivity index, percentage yield difference, relative crowding coefficient, aggressivity, competitive ratio and actual yield loss were employed to assess interspecific interactions and their impact on biomass productivity. ResultsResults show that intercropping sunn hemp at maize planting or the V15 maize growth stage can reduce stand density to 32 plants m−2 without reducing sunn hemp biomass yield. The land equivalent ratio was highest (2.20), with intercropping at the V15 maize growth stage and lowest (2.09) with simultaneous intercropping at maize planting. The relative crowding coefficient was highest (34.4) at the V15 maize growth stage at 32 plants m−2 stand density and lowest (−45.9) with simultaneous intercropping at planting at the same stand density. Intercropping during the R1 maize growth stage influenced competition on sunn hemp with the highest actual yield loss of − 0.07. Competitive ratios were significantly higher for maize (26.19) and sunn hemp (0.16) with R1 and V15 maize growth stage intercropping, respectively. However, sunn hemp's actual yield loss was higher (0.25) with intercropping during the V15 maize growth stage than in sole cropping. ConclusionsIntercropping sunn hemp both simultaneously with maize planting and during the V15 maize growth stage with a stand density of 32 plants m−2 demonstrated enhanced biomass productivity, thereby offering viable intensification choices. The utilization of multiple intercropping indices can contribute to a more comprehensive and precise evaluation of interspecies interactions, consequently leading to improved decision-making.

Feeding spent hemp biomass to lactating dairy cows: Effects on performance, milk components and quality, blood parameters, and nitrogen metabolism

The legalization of industrial hemp by the 2018 Farm Bill in the United States has driven a sharp increase in its cultivation, including for cannabinoid extraction. Spent hemp biomass (SHB), produced from the extraction of cannabinoids, can potentially be used as feed for dairy cows; however, it is still illegal to do so in the United States, according to the US Food and Drug Administration Center for Veterinary Medicine, due to the presence of cannabinoids and the lack of data on the effect on animals. To assess the safety of this byproduct as feed for dairy cows, late-lactation Jersey cows (245 ± 37 d in milk; 483 ± 38 kg body weight; 10 multiparous and 8 primiparous) received a basal total mixed ration (TMR) diet plus 13% alfalfa pellet (CON) or 13% pelleted SHB for 4 wk (intervention period [IP]) followed by 4 wk of withdrawal period (WP), where all cows received only the basal TMR during WP. The dry matter intake (DMI), body weight, body condition score, milk yield, milk components, and fatty acid profile, blood parameters, N metabolism, methane emission, and activity were measured. Results indicated that feeding SHB decreased DMI mainly due to the low palatability of the SHB pellet, as the cows consumed only 7.4% of the total TMR with 13.0% SHB pellet offered in the ration. However, milk yield was not affected during the IP and was higher than CON during the WP, leading to higher milk yield/DMI. Milk components were not affected, except for a tendency in decreased fat percentage. Milk fat produced by cows fed SHB had a higher proportion of oleate and bacteria-derived fatty acids than CON. The activity of the cows was not affected, except for a shorter overall lying time in SHB versus CON cows during the IP. Blood parameters related to immune function were not affected. Compared with CON, cows fed SHB had a lower cholesterol concentration during the whole experiment and higher β-hydroxybutyric acid during the WP, while a likely low-grade inflammation during the IP was indicated by higher ceruloplasmin and reactive oxidative metabolites. Other parameters related to liver health and inflammatory response were unaffected, except for a tendency for higher activity of alkaline phosphatase during IP and a lower activity of gamma-glutamyl transferase during WP in the SHB group versus CON. The bilirubin concentration was increased in cows fed SHB, suggesting a possible decrease in the clearance ability of the liver. Digestibility of the dry matter and protein and methane emission were not affected by feeding SHB. The urea, purine derivatives, and creatinine concentration in urine was unaffected, but cows fed SHB had higher N use efficiency and lower urine volume. Altogether, our data revealed a relatively low palatability of SHB affecting DMI with minimal biological effects, except for a likely low-grade inflammation, a higher N use efficiency, and a possible decrease in liver clearance. Overall, the data support the use of SHB as a safe feed ingredient for lactating dairy cows.