Clover Mixture Research Articles

FORAGE YIELD AND QUALITY OF INTERCROPPED ANNUAL RYEGRASS WITH BERSEEM CLOVER SOWN AT DIFFERENT SEED MIXTURE RATIOS UNDER RAINFALL CONDITIONS OF MEDITERRANEAN CLIMATE

This research was carried out under rainfall conditions of Mediterranean climate with the aim to study the effects of different seed mixture ratios on forage yield and quality characteristics of mixture. Annual ryegrass sown as pure produced higher green forage yield than berseem clover sown as pure and the mixtures. In the mixture of berseem clover at 20% seed rate and pure annual ryegrass, higher hay yields were determined compared to the other mixtures. As the seed rate of berseem clover decreased, the proportion of berseem clover in the mixture yield and the crude protein ratio of the herbage decreased linearly. In terms of total LER, BC80-AR20 and BC20-AR80 mixtures were the two most advantageous mixtures, while the aggressivity value of annual ryegrass showed a positive value and became the dominant species. Pure sown berseem clover had lower ADF, NDF and higher crude protein content than pure sown annual ryegrass and other mixtures tested. According to these results, it can be said that berseem clover can be included in the mixture at low seed rates for high forage yield under rainfall conditions, while berseem clover can be grown as pure for high forage quality.

Selection environment impacts genetic gains for persistence in three temperate perennial forage grasses

Grasses and legumes are regularly grown in association, despite often being unbalanced or incompatible. This study was intended to conduct selection for persistence in three perennial grass species that have compatibility issues with alfalfa (Medicago sativa L.) or red clover (Trifolium pratense L.) and are poorly adapted to management-intensive rotational grazing. Five cycles of selection for persistence were conducted over a 24-year period for three grass species (reed canarygrass, smooth bromegrass, and timothy) in each of five selection environments: alfalfa mixture, red clover mixture, monocultures with a three-harvest hay management, tall fescue mixture with frequent defoliation, and monocultures with frequent defoliation. Selection in the two legume mixtures led to significant increases in persistence only when evaluated in legume mixtures. Selection responses were strongest when evaluated under the same legume as in the selection environment, indicating some species specificity. Selection for persistence under frequent defoliation was successful under both conditions (monoculture and tall fescue mixture), but led to no changes when evaluated with legumes. For these three grass species, cultivar development for use in mixture with legumes or for use in management-intensive rotational grazing should be based on a selection environment that mimics, as close as possible, the target production environment.

Effect of Acacia mearnsii forage or tannin extract on rumen dry matter and crude protein degradation.

This study investigated rumen degradation kinetics of dry matter (DM) and crude protein (CP) in compound feed with different tannin extract inclusions and Acacia mearnsi forage (AMF) relative to dairy feeds (perennial ryegrass+white clover mixture pasture, maize silage, lucerne hay and Themeda triandra hay). The compound feed had 0.75%, 1.5% and 3% tannins extract inclusions while the control was a commercial compound feed. Triplicates of each feed per incubation period were incubated in two fistulated Jersey cows for 0, 6, 24, 48, 72, 96 and 120 h, resulting in six replicates per feed. Tannin extract inclusions in compound feed only affected (p < 0.05) the (a) fraction, degradation rate and potential degradability (PD) for DM degradation, and affected (p < 0.05) the (a) and (b) fractions, as well as PD for CP degradation. The (a) fraction and degradation rate for DM degradation changed linearly (p < 0.05). The (a) fraction, PD and effective degradability (ED) of DM degradation changed quadratically (p < 0.05). Except for the degradation rate, the feed type affected (p < 0.05) the degradation parameters in both DM and CP degradations. For DM and CP degradations, (a) fraction was similarly the least in Themeda triandra hay and AMF but similarly the highest in maize silage, perennial ryegrass+white clover mixture pasture and lucerne hay. The (b) fraction was the least in AMF for both DM and CP degradations but the highest for pasture's DM degradation and similarly the highest in maize silage, lucerne hay and T. triandra hay for CP degradation. The PD was the least in AMF for both DM and CP degradations and similarly the highest in pasture DM but similarly the highest in perennial ryegrass+white clover mixture pasture, maize silage and lucerne hay for CP degradation. Furthermore, the ED was the lowest in AMF and the highest for perrenial ryegrass + white clover mixture pasture for DM degradation and same trend was observed for CP degradation whereby perrenial ryegrass + white clover mixture pasture, maize silage and lucerne had the highest ED. Digestible undegraded protein was the highest in AMF and similarly the least in dairy feeds. Tannin source inclusion in ruminant diets should be moderate to prevent rumen DM or CP degradation limitation.

Estimation of botanical composition of forage crops using laboratory-based hyperspectral imaging and near-infrared spectrometer measurements

Harvested forage is the main raw feed for ruminant animals in Sweden, and is commonly cultivated in mixed stands of legume and grass species. The fraction of legume on a dry matter basis, known as botanical composition (BC) is a very important indicator of forage quality. In this study, hyperspectral imaging and near-infrared spectrometer (NIRS) based methods were used to estimate BC, to overcome the shortcomings of hand separation, which is time and resource consuming. Timothy and red clover mix samples were collected from different harvests in 2017–2019 from multiple sites in Northern Sweden and hand separated. The samples were synthetically mixed to 11 different BC levels, i.e., 0–100 % clover content. Two different instruments (Specim shortwave infrared (SWIR) hyperspectral imaging system and Foss 6500 spectrometer) were used to collect spectral data of samples milled to two levels of coarseness. Three different regression analyses: partial least squares regression (PLSR), support vector regression (SVR) and random forest regression (RFR), were used to build BC estimation models. The effects of the milling particle sizes and the different instruments on the performances of the models were compared. The data from second harvest in 2019 were used for independent validation as evaluation, and the rest of data were randomly split for model calibration (75 %) and validation (25 %). The models were iteratively run 1000 times with different splits, to check the effect from the splitting of calibration and validation datasets. Among different regression analyses, PLSR performed best, with mean Nash-Sutcliffe efficiency (NSE) for model evaluation from 0.76 to 0.87, varying for different instruments and milling sizes. Finer milling made the model accuracies slightly higher. This study developed quick and robust methods to determine the BC of timothy grass and red clover mixtures, which can provide useful information for farmers or researchers.

Evaluating the effects of cotton intercropping on cool‐season perennial forage persistence, forage mass, and nutritive value in the southeastern United States

AbstractIntegrated forage–row cropping systems provide important agronomic and economic benefits to producers. However, little attention has been given to incorporating forages into row crop systems unique to the southeastern United States. This study assessed the viability of intercropping cotton (Gossypium hirsutum L.) on perennial, cool‐season legumes during the summer months in the Southeast Coastal Plain over two production years. Treatments included a weedy fallow, annual ryegrass (ARG; Lolium multiflorum Lam.) monoculture, a red clover (RC; Trifolium pratense L.) and white clover (WC; Trifolium repens L.) mixture, and a three‐species mixture of ARG, RC, and WC. Plots were established in fall 2020 with forage grown until May 2021 and 2022, when plots were strip‐tilled and planted with cotton. Cotton was managed with minimal herbicide use to preserve perennial clovers. Results indicated WC was more persistent than RC (&gt;40 plants m−2 vs. &lt;40 plants m−2), and the presence of perennial clovers suppressed weeds at similar levels to the ARG monoculture (35 weeds m−2) during the second spring. Perennial clovers grew taller (4–5 cm) when mixed with ARG. The presence of clovers mixed with ARG during the second spring reduced acid detergent fiber (ADF) concentration and increased crude protein (CP) concentration (280 g ADF kg−1; 167 g CP kg−1) compared to the ARG monoculture (315 g ADF kg−1; 126 g CP kg−1). Benefits of intercropping perennial forages with cotton were maximized during the second year of growth, but future work is necessary to improve stand survival.

Nutrient composition, fermentation characteristics and mass balance of press juice and press cake obtained from biorefining of grass‐clover and red clover silage

AbstractBiorefining is seen as a potential method to produce protein‐rich feed for monogastric farm animals from grassland, which does not compete with human nutrition. Therefore, a new biorefinery facility was constructed and tested in this experiment by using silages from grass clover mixture and red clover. After biorefining, press juice was stored for further use while press cake was re‐ensiled. Samples from silage, press juice, fresh press cake and re‐ensiled press cake were analysed for nutrient composition, fermentation parameters, amino acids (AA) and biogenic amines (BA) concentrations. Furthermore, digestibility of silage and re‐ensiled press cake was tested in wethers. We found that press juice contained about 205 g crude protein (CP), more than 180 g crude ash and more than 130 g volatile organic compounds (VOC, all values per kg dry matter [DM]). Furthermore, press juice had an unfavourable AA ratio for use as a monogastric feed (methionine and cysteine were reduced). Forage type hardly affected nutritive value of press juice. Re‐ensiling of press cake was successful as a sufficient decrease of pH and VOC concentration was observed. Press cake had 26–36 g/kg DM lower CP content and 0.77–1.12 MJ/kg DM lower metabolisable energy content than silage with greater differences in red clover than in grass clover mixture. Press juice can be used as feed in monogastric animals, but its use is limited due to its low CP content and unfavourable AA profile. Press cake could be an appropriate feed for ruminants, especially dry cows or heifers.

Response of Soil Microorganisms to and Yield of Spelt Wheat following the Application of Bacterial Consortia and the Subsequent Effect of Cover Crops in Organic Farming

In modern agriculture, more and more attention is being paid to the use of microorganisms that can increase crop productivity and quality even under adverse weather conditions. Due to the declining biodiversity of crops and the occurrence of soil erosion and nutrient losses, the introduction of cover crops (CC) can be a positive crop management technique. In the field study presented here, the effect of growing spring barley with CCs applied simultaneously with bacterial consortia on the ratio of the total number of bacteria to actinobacteria (B/A) and the number of fungi in the soil was evaluated. The biomass yield of CCs and the subsequent effect on the yield of spelt wheat grown with the application of bacterial consortia were also evaluated. The bacterial consortia applied included consortium 1, comprising Bacillus subtilis, Bacillus amyloliquefaciens, and Pseudomonas fluorescens, and consortium 2, comprising Bacillus subtilis, Bacillus amyloliquefaciens, Pseudomonas fluorescens, and Azotobacter chroococcum. The CCs were red clover, red clover + Italian ryegrass, and Italian ryegrass. The most favorable B/A ratio and the highest number of fungi were obtained after growing spring barley with a CC consisting of a mixture of red clover and Italian ryegrass when using bacterial consortium 2. These conditions additionally had the most favorable influence on spelt wheat. The combination of such a forecrop with the application of bacterial consortium 2 resulted in the highest yields of spelt wheat.

Effect of cover crops on soil health at different landscape positions

AbstractSoil health is crucial to reaching high yields, and growing cover crops can help improve soil conditions. The goal of this study is to determine the effects of cover crops on soil health using potential respiration, potential nitrogen mineralization, and aggregates stability as indicators of soil health. The study has been conducted since 2019 at the University of Kentucky Spindletop Farm, Lexington, KY, and involves three landscape positions receiving a treatment with cereal rye, cereal rye–crimson clover mixture, and fallow soil. This study emphasized that cover crops can enhance potential respiration and microbial activity over landscape positions, with rye being more beneficial than the mixture treatment. However, cover crops were also beneficial for aggregate stability but not for potential nitrogen mineralization.

Assessing relationships of cover crop biomass and nitrogen content to multispectral imagery

AbstractCover crops provide valuable roles in sustainable agriculture, provided they produce enough biomass. To accurately measure their services to field management, spatial estimates would be useful to producers. This study used multispectral drone imagery to produce maps of normalized difference vegetation index (NDVI), normalized difference red edge index (NDRE), and a digital surface model (DSM) of cover crop plots on sandy, Mid‐Atlantic soils. Cover crops included cereal rye (Secale cereale), mixtures of rye and crimson clover (Trifolium incarnatum), and mixtures of rye and hairy vetch (Vicia villosa). Their biomass was sampled in the spring of 2019, 2020, and 2021, dried, weighed, and analyzed for total nitrogen (N) content. Measurements of NDVI became saturated (i.e., reached a linear plateau) at 3.86 Mg biomass ha−1, NDRE at 5.72 Mg biomass ha−1, and the DSM at 5.11 Mg biomass ha−1. The measured N content became saturated at 80.9, 139.1, and 75 kg N ha−1 for NDVI, NDRE, and the DSM, respectively. Based on log transformations, NDVI was a stronger predictor of biomass and N, but not C:N. The NDRE was important for biomass, N, and C:N, while the DSM interactions with cover crop species helped predict both the N content and C:N of cover crop tissues. Accumulated growing degree days was important as an individual variable for biomass and N and as an interaction with cover crop species.

Availability of dissolved organic carbon drives differences in microbial nitrogen‐cycling processes between two sites with cover crops interseeded into corn

AbstractInterseeding cover crops into corn has been proposed as a technique to extend the cover crop growing window, but interseeded cover crops may reduce nitrogen (N) availability and compete with corn for available nutrients. To assess N‐cycling dynamics in soils where cover crops have been interseeded into corn for 1 or 2 years, plots were established in duplicate at two sites in Michigan with differing edaphic properties. Annual ryegrass (Lolium multiflorum Lam.), crimson clover (Trifolium incarnatum L.), oilseed radish (Raphanus sativus L.), or a mixture of ryegrass and clover were interseeded into corn at the V3 or V6 stages of corn growth and compared to control plots that did not receive cover crops. We measured active carbon (C) and N pools during the growing season and after harvest as well as potential activities of microbially mediated nutrient‐cycling processes via extracellular enzymes, nitrification, and denitrification. We found that after 2 years, interseeded cover crops had little to no effect on active pools of C and N or on microbial nutrient‐cycling activities, but cover crop growth was severely limited in some site years. However, we observed major differences in these parameters between sites, with finer textured soils exhibiting increased dissolved organic C availability and greater peptidase activity compared to coarser‐textured soils. Our results reveal important spatial and temporal trends that suggest greater C availability can lower the potential for N loss while maintaining a rapid flux of N through the N cycle.

Effect of mixing ratios and spraying with microelements on the growth and yield of forage for a mixture of oats and clover

A field experiment was carried out in the fields of the Agricultural Research Station-College of Agriculture, University of Basra, during the winter season of 2021-2022. To study the effect of seeding rates of both oats and Egyptian clover with mixing percentages of 100% oats, 75% oats + 25% clover, 50% oats + 50% clover, 75% clover + 25% oats, 100% clover as the first factor and microelements at a concentration of 1500, 3000 and 4500 ppm as a second factor. The time for spraying with micro-elements was in the branching stage, 7-10 days after the first spray and 7-10 days after the second spray. The experiment was carried out in a factorial experiment with three replications, according to a randomized complete block design, RCBD. Three cuttings were taken during the crop’s growth period. The height of the oats and clover plants, the number of oat tillers, the number of clover branches, the weight ratio of leaves to tillers and stems, and the amount of green and dry forage were measured. The results of the study showed that the different ratios of mixing oats and clover crops contributed to the production of the studied traits; 50% of oats + 50% of clover in the second cutting recorded the highest yield of green fodder (66.84 tons ha-1) and dry fodder yield (22.37 tons ha-1). As for the effect of concentrations of microelements, the level of 4500 ppm achieved superiority in all growth characteristics of all cutting, and the highest yield was recorded in green fodder (65.57 tons ha-1) and dry forage (22.44 tons ha-1) at the second cutting. 50% oats + 50% clover at the level of 4500 ppm gave the highest yield for green fodder (69.66 tons ha-1) and dry (24.81 tons ha-1). Keywords: Mixture; Spraying; micro-nutrients; green fodder; Avena sativa; Clover.

Chicory stimulates companion legume species to fix more biological nitrogen

Abstract Purpose Chicory (Cichorium intybus) scavenges more soil mineral nitrogen (N) than perennial ryegrass (Lolium perenne). A glasshouse study was conducted to test whether (a) the percentage of N derived from the atmosphere (%Ndfa) by a companion legume differs when grown with chicory or perennial ryegrass, and (b) there is an optimal ratio of non-legume:legume in a pasture mix that maximises biological N2 fixation. Methods Chicory or perennial ryegrass was grown as a monoculture, or in a mixture with either lucerne (alfalfa, Medicago sativa) or subterranean clover (Trifolium subterraneum) at 25:75, 50:50 or 75:25 ratio (non-legume:legume based on plant numbers). Monocultures of lucerne and subterranean clover were included as controls. Results All treatments containing chicory extracted more mineral N from the soil than corresponding treatments containing perennial ryegrass. Subterranean clover %Ndfa was greater than lucerne. Combining lucerne with chicory in a 50:50 or 75:25 mixture increased the efficiency of N2 fixation by &gt; 20%. Growing chicory with subterranean clover in mixtures of 50:50 or 75:25 resulted in the highest %Ndfa for growth among all treatments (P &lt; 0.05). However, the amounts of N2 fixed by subterranean clover in the perennial ryegrass-subterranean clover mixture were similar to those in the chicory-subterranean clover mixture since dry matter accumulation from subterranean clover was higher when grown with perennial ryegrass. Conclusion The %Ndfa of legumes was greater when grown with chicory than perennial ryegrass. Chicory mixed with subterranean clover or lucerne in 50:50 ratios provided the optimum balance between legume dry matter yield and N2 fixation.

Using perennial groundcover crops to suppress weeds and thrips in the southeast cotton belt

AbstractModern cotton production (Gossypium hirsutum L.) in the United States relies on chemical and physical inputs that increase the environmental and monetary costs of managing the crop. Perennial groundcover crops (PGCC) may reduce inputs by persisting in the interrow spaces of the cotton crop during summer months. A 2‐year field study was conducted in Florence, SC, to evaluate growing PGCCs with cotton using a 4 × 4 Latin square consisting of four cover crop treatments: (1) a fallow, unplanted control, (2) annual ryegrass (Lolium multiflorum Lam.) monoculture, (3) a binary red clover (Trifolium pratense L.) and white clover (Trifolium repens L.) mixture, and (4) a trinary mixture of annual ryegrass, red clover, and white clover. Fallow and annual ryegrass treatments were killed with a burndown herbicide application, while treatments containing clovers were mowed. Plots were strip‐tilled and planted with cotton in May each year. Interrow biomass, weed and thrips populations, and perennial clover populations were collected from June to October along with annual lint yields from cotton harvest in October. Results indicated that interrow biomass (2000–3000 kg ha−1), weeds (20 weeds m−2), and thrips (five thrips per five plants−1) populations were lowest in treatments containing perennial clovers, but drought and heat stress reduced clover stands within two growing seasons. Lint yield was not affected by incorporating perennial clovers into the interrow spaces of the crop. Perennial groundcover crops may provide an effective alternative to chemical weed control in cotton, but necessitate management changes to be viable in the southeastern United States.

Determination in Forage Yield and Quality of Chicory and Different Plants Mixtures in Grazing Maturity Period

This study was conducted to determine forage yield and quality of chicory (Cichorium inthybus L.) in a pure stand and a simple pasture (two-species) in the grazing maturity period. The experiment design was a Randomized Block Design with 3 replications. The experimental site was located on the grounds of the Ondokuz Mayıs University Agricultural Faculty during the 2017 and 2018 growing periods. In this study, chicory (C), orchardgrass (OG), and red clover (RC) were grown as forage plant materials in a rainfed cropping system in North Türkiye. Simple pastures comprised of 80%C + 20%OG, 60%C +40%OG, 40%C + 60%OG, 20%C + 80%OG, 80%C + 20%RC, 60%C + 40%RC, 40%C + 60%RC, 20%C + 80%RC. Five sequential harvests were made when chicory plants reached 25 cm of plant height in both years. The average plant height ranged from 17.3 to 35.6 cm, and 29.1 to 38.3 cm in 2017 and 2018 respectively. The highest fresh forage yield was determined in red clover mixtures (6519-5443 kg/da) in 2017 and 80%C+20%RC mixture (as 7137 kg/da) in 2018. Total dry matter production was ranged from 216 to 1238 and 279 to 1164 kg/da in 2017 and 2018, respectively. In pure stand chicory pasture, dry matter production was evaluated 216 kg/da in 2017 and 908 kg/da in 2018. Considering the calculated area equivalence ratios (LER) of mixed planting plots in both years and in all forms, it was determined that all mixtures were superior to plain plantings (LER≥1).

Plantain dominated in mown mixed swards, but produced less than the original ryegrass-dominant sward

This trial determined the effect of compost on mixed species pasture. Existing (five year old) perennial ryegrass provided the control. A mixture of perennial ryegrass, white clover and plantain was sown into sprayed-out treatment plots, giving five replicates of six treatments. One treatment was direct drilled another was cultivated and drilled. The remaining three were spread with compost (50, 100 or 150 t/hawet weight) and cultivated. Plots were mown at 35 d intervals for two years with clippings returned to the sward. Although grass established well at 500 plants/m2 plantain quickly came to dominate in all renewed plots, at 55-61% of DM in year 1 and 57-79% of DM in year 2. Grass contributed 29-35% of DM in year 1 and 10-30% in year 2, with clover 5-8% in year 1 and 10-14% in year 2. Grass dominated control plots (73and 82% DM, respectively), while clover contributed more DM in absence of plantain (22% and 17%). Compost did not affect production. Cultivation gave a slight advantage over direct drilling, but new swards produced &lt;50% the total DM of the control (P&lt;0.05). Substantial investment was involved, so rewards need to be considerable to recoup costs.

14 Mitigation Strategies for Heifer Development on ‘KY-31’ Tall Fescue

Abstract Tall fescue (Schedonorus arundinaceus) is the predominant cool-season perennial forage in the Eastern U.S. However, a symbiotic endophyte reduces performance of animals grazing tall fescue. This results in losses of around $2 billion annually. Due to the vasoconstriction caused by the endophyte, a decrease in conception rates among cows and heifers consuming tall fescue has been observed. With rising input costs, it is necessary to explore alternative mitigation strategies these production losses. The objective of this study was to mitigate the toxic effects of ‘KY 31’ tall fescue by limit-grazing cool-season annuals as an alternative to feed supplementation. In January 2022, 48 heifers [14 months of age; 365.9 ± 11.89 kg body weight (BW)] were randomly assigned to tall fescue only, tall fescue with supplemental feed at 1% of BW, tall fescue with limit grazing of cool-season annuals for 24 h per week, and cool-season annuals only. Four animals grazed in each of three replicated paddocks per treatment. Cool-season annual pasture was a mixture of crimson clover (Trifolium incarnatum), annual ryegrass (Lolium multiflorum), and oat (Avena sativa). Body condition scores (BCS), hair coat scores (HCS), and BW were recorded every 30 d. Forage samples were taken for biomass, nutritive value, and ergovaline concentration every 30 d. On April 1, 2022, heifers were artificially inseminated (AI), and conception rates were determined 45 d after AI. Data were analyzed using the Glimmix procedure of SAS 9.4 (SAS Inst, Cary, NC) with α = 0.05. There were no differences among treatments in HCS at any weigh date (P &amp;gt; 0.05). The BCS for all treatments was less in February than January or March (5.6, 6.1, 6.1, respectively; P &amp;lt; 0.0001), but there were no differences among treatments at any sampling date (P &amp;gt; 0.05). Conception rates were not different among treatments (P &amp;gt; 0.10) but averaged 75, 67, 42, and 50% for the continuous-cool season, limit graze, supplemental feed, and tall fescue treatments, respectively. Crude protein (CP) concentrations for the control and limit grazing fescue treatments were greater than the limit grazing cool-season annual treatment, continuous grazing cool-season annual treatment, and the supplemental feed treatment (13.5, 10.7, 10.4, and 8.9%, respectively, (P &amp;lt; 0.012). Neutral detergent fiber (NDF) and acid detergent fiber (ADF) were different among the supplemental treatment when compared with the limit grazing fescue, limit grazing cool-season annual, control, and continuous cool-season annual (48.2 vs 64.7% NDF and 25.8 vs. 37.0% ADF; P &amp;lt; 0.0361). At this time, the results indicate that limit grazing cool-season annual forages may be an advantageous option to mitigate fescue toxicosis in replacement heifers grazing tall fescue pastures in the spring.

Consortia of Plant Growth-Promoting Rhizobacteria and Selected Catch Crops for Increasing Microbial Activity in Soil under Spring Barley Grown as an Organic Farming System

In order to protect and remediate soils, organic farming methods have grown in popularity. The aim of the study was to evaluate the effect of rhizobacteria (Bacillus subtilis, Bacillus amyloliquefaciens, Pseudomonas fluorescens) and catch crops (undersown red clover alone, undersown Italian ryegrass alone and a mixture of clover and ryegrass) on the microbiological activity of the soil under organic spring barley. In 2019–2021, a field experiment was carried out on an organic farm, randomly in eight variants, each in three repetitions. The following parameters were analyzed: enzymatic activity of dehydrogenases (DHA), acid phosphatase (PAC) and catalase (CAT), soil fertility index (BIF), and a number of selected physiological groups of microorganisms (molds, bacteria, and actinomycetes). Compared to the control variant (without catch crops and bacteria), the values of DHA, CAT, and BIF increased significantly in the variant in which rhizobacteria and catch crops were used simultaneously. The highest BIF, of 32, was obtained in 2019, after the application of red clover catch crop + Italian ryegrass + rhizobacteria. PAC activity dropped significantly after the application of the bacterial consortium alone and was lower than the control by an average of 30%.

Fatty Acid, Carotenoid and Fat-Soluble Vitamin Composition of Multispecies Swards Grown in Ireland—Implications for a Sustainable Feed in Dairy Farming

Although traditional ryegrass pastures are still commonly used, they require intense management and input and do not perform well during the summer months. Multispecies systems have been recognised as more sustainable, needing less fertiliser and being tolerant to drought and heat. While data on monoculture system fat composition exist, information for multispecies is scarce. The present study compared the fatty acid (FA), carotenoid and fat-soluble composition of a multispecies system (consisting of perennial ryegrass, timothy, white clover, red clover, chicory and plantain) (MULTI) with two other conventional grazing systems (monoculture perennial ryegrass (PRG) and a binary mixture of perennial ryegrass and white clover (PRG+WC)) over the Irish late-summer grazing season of dairy cattle (July–September). The results showed that the three systems had similar levels of FAs (p &gt; 0.05), with mean α-linolenic acid values of 20.00 mg/g in PRG, 18.51 mg/g in PRG+WC, and 17.90 mg/g in MULTI and mean linoleic acid values of 3.84 mg/g in PRG, 4.16 mg/g in PRG+WC, and 4.39 mg/g in MULTI. Fourfold and twofold increases in the concentrations of α-linolenic acid and linoleic acid, respectively, were observed throughout July–September. Variations in stearic acid concentrations were not significant (p &gt; 0.05), and palmitic acid concentrations increased over time (p &lt; 0.05). The average values of lutein (36.68 mg/kg in PRG, 31.26 mg/kg in PRG+WC, and 35.75 mg/kg in MULTI) and α-tocopherol (2.28 mg/kg in PRG, 1.49 mg/kg in PRG+WC, and 1.83 mg/kg in MULTI) were similar among the grazing systems (p &gt; 0.05), and the average β-carotene value was 25% higher in monoculture ryegrass (140.74 mg/kg) than in the multispecies (102.51 mg/kg) (p &lt; 0.05). Nonetheless, the levels of β-carotene found in the multispecies were still above the recommended intake required for ruminants. In conclusion, multispecies pastures could be included in dairy cattle production systems as a sustainable alternative to traditional pastures while also providing typically adequate sources of fats for animal diets.

Tillage and cover crop mixtures interseeded in maize–soybean in the upper Midwest

AbstractEcosystem benefits of winter‐killed annual cover crops are less studied than winter hardy annuals. The objectives of this study were to determine (1) the effects of tillage practices and cover crop mixtures on biomass and soil cover of cover crops seeded into nearly mature maize (Zea mays L.) and soybean [Glycine max (L.) Merr.] and (2) if cover crop biomass can be estimated from soil surface coverage measurements. The study was conducted within two long‐term tillage trials from 2016 to 2018. Tillage included conventional—(CT), strip—(ST), and no‐till—(NT). Cover crops included annual ryegrass (AR; Lolium multiflorum L.); AR and crimson clover (CC; Trifolium incarnatum L.) mixture (ARCC); AR, CC, and forage radish (FR; Raphanus sativus L.) mixture (ARCCFR); and no‐cover (NC). Seeding rates for AR, ARCC, and ARCCFR were 28, 36, and 40.5 kg ha−1, respectively. The ARCCFR mix produced the most biomass (256 kg ha−1), followed by AR (174 kg ha−1) and ARCC (165 kg ha−1). Cover crop biomass was 260 and 136 kg ha−1 in maize and soybean; and 218, 201, and 177 kg ha−1 in CT, ST, and NT, respectively. Cover crop soil coverage between rows was 25% in maize and 14% in soybean. Cover crop biomass was associated with soil surface coverage (R2 = 0.841). Given that cover crop biomass drives ecosystem services associated with cover crops, limited biomass and ground coverage of winter killed cover crops seeded into nearly mature maize and soybean may not add ecosystem services in the upper Midwest.

Effect of grassland cutting frequency, species mixture, wilting and fermentation pattern of grass silages on in vitro methane yield

Mitigating enteric methane (CH4) emissions is crucial as ruminants account for 5% of global greenhouse gas emissions. We hypothesised that less frequent harvesting, use of crops with lower WSC concentration, ensiling at low crop dry matter (DM) and extensive lactic acid fermentation would reduce in vitro CH4 production. Timothy (T), timothy + red clover mixture (T + RC) or perennial ryegrass (RG), cut either two or three times per season, was wilted to 22.5% or 37.5% DM and ensiled with or without formic acid-based additive. Silages were analysed for chemical composition and fermentation products. In vitro CH4 production was measured using an automated gas in vitro system. Methane production was, on average, 2.8 mL/g OM lower in the two-cut system than in the three-cut system (P < 0.001), and 1.9 mL/g OM lower in T than in RG (P < 0.001). Silage DM did not affect CH4 production (P = 0.235), but formic acid increased CH4 production by 1.2 mL/g OM compared to the untreated silage (P = 0.003). In conclusion, less frequent harvesting and extensive silage fermentation reduce in vitro CH4 production, while RG in comparison to T resulted in higher production of CH4.