Grass-legume Mixtures Research Articles

PENGARUH RASIO KARBON-NITROGEN DALAM ENSILAGE CAMPURAN MUKUNA LOKAL (MUCUNA SP) DAN RUMPUT KUME (SORGHUM PLUMOSUM VAR. TIMORENSE) SEGAR TERHADAP KANDUNGAN NUTRISI PRODUK (The effects of carbon-nitrogen ratio in ensilage of local mucuna (mucuna sp.) And...

The main problem in preservation of protein source forages in silage making is spoilage due to high buffering characteristic of protein. This might relates to low carbon-nitrogen (C-N) ratio in these plants. This study aimed at determining the best level of C-N ratio in ensilage process of a grass-legume mixture. A 3x4 completely randomized design (CRD) was deployed to test three C-N ratio levels as treatments. The treatments were CN20 (Mucuna sp + kume grass + rice bran to reach C-N ratio of 20, or 30 (CN30) or 40 (CN40). Variables measured were dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), and crude fiber (CF) content of the silage. Data were analyzed using General Linear Model for CRD with an alfa value of 0.05. Treatment differences were determined using Duncan test. The results showed that C-N ratio had high significant effects on DM content (ranged from 22.5 to 32.0%), and CP content (ranged from 7.5 to 9.6%). Significant treatment effects were detected in OM content (ranged from 90.5 to 91.8%), and EE content (ranged from 2.82 to 3.66%). Meanwhile, CF was not effected by C-N ratio (ranged from 39.0 to 3.0%. 44.2%). It could be concluded that C-N the ratio of 30 is the best treatment in silage making using mixture of lelehanak-kume grass as it shows the highest OM content and had no significant difference with CN20 in CP content.

Study of the nutritional and productive value of perennial legume-grass mixtures on reclaimed lands of the Upper Volga region

Relevance. The article is devoted to the relevant problem of assessing the productive and nutritional value of complex grass mixtures of various families, as well as assessing the economic and agro-energy efficiency of cultivating legume-grass mixtures for fodder.Methods. Experiments were laid at the VNIIMZ experimental agro-reclamation site in 2019–2021. The objects of research were herbal mixtures: 1) oriental goat's rue + cereals (60:40%); 2) variable alfalfa + red clover + meadow timothy (30:35:35%); 3) variable alfalfa + red clover + meadow fescue (30:35:30%); 4) clover-timothy mixture (45:55%). Control — clover-timothy mixture (60:40%), traditional for the production of green mass. The area of the experiment is 6.1 ha, the placement of the options is randomized, in three tiers, the repetition is three times. The use of grass stands is two-cut, agricultural technology is generally accepted. The studies were carried out in accordance with the methodological recommendations adopted in fodder production and agriculture. Statistical processing was carried out by the method of dispersion analysis using computer programs.Results. High yields of grass mixtures based on goat's rue with cereals were obtained — green mass up to 49.9 t/ha, dry matter — up to 14.1 t/ha, while the timothy mixture used as a control — only 23.8 and 6 .78 t/ha, respectively. At the same time, it was found that the collection of fodder protein units, digestible protein and energy productivity were the highest in legume-grass mixed crops based on goat's rue with cereals (13.97 t/ ha, 1.50 t/ha and 167.7 GJ/ha) and grass mixtures based on clover, alfalfa and timothy grass (9.17 t/ha, 1.03 t/ha and 115.2 GJ/ha), while clover-timothy grass mixture provided only 5.49 t/ha, 0.57 t/ha and 58.3 GJ/ ha, respectively (significance of differences p < 0.05). Grass mixtures from goat's rue, alfalfa and red clover with intensive varieties of cereal grasses provide the maximum amount of nutrients per unit area, improve the quality of fodder.

Mixture of Alfalfa, Orchardgrass, and Tall Fescue Produces Greater Biomass Yield in Southwest China

The current study investigated the influence of mixture composition on the biomass yield and early establishment of legume–grass mixtures. The legume species alfalfa (Medicago sativa L. (A)), white clover (Trifolium repens L. (WC)), and red clover (Trifolium pratense L. (RC)) and grass species orchardgrass (Dactylis glomerata L. (O)), tall fescue (Festuca arundinacea Schreb. (TF)), and perennial ryegrass (Lolium perenne L. (PR)) were grown in monocultures and in different legume–grass mixtures. Legume–grass mixtures (M1: WC + O + TF; M2: A + O + TF; M3: A + WC + O + TF; M4: RC + WC + O + TF; M5: A + WC + O + TF + PR; M6: RC + WC + O + TF + PR; and M7: A + RC + WC + O + TF + PR) were sown in a legume–grass seeding ratio of 3:7. The results showed that M2 had the greatest two-year average biomass yield (12.92 t ha−1), which was significantly (p < 0.05), 4.7%, 5.4%, 15.8%, and 29.1% greater than that of WC monoculture, M7, M4, and M1, respectively. The grass biomass yield proportions of all mixtures significantly decreased, while legume biomass yield proportions significantly increased in the second year compared to the first year of establishment. The land-equivalent ratio values of M2 and M4 were greater than 1 in each cutting period. The competition rate of grasses gradually decreased with prolonged establishment time. Overall, the biomass yield, legume and grass biomass yield proportions, land equivalent ratio, and competition rate data highlighted that M2 is the best choice to achieve greater productivity and early establishment in southwest China.

Effects of Legume–Grass Ratio on C and Nutrients of Root and Soil in Common Vetch–Oat Mixture under Fertilization

Legume–grass mixture can greatly improve soil fertility to support the sustainable productivity. Root litter is an important source of soil organic matter, but its link with soil nutritional status in forage mixtures is not clear. This study was aimed to uncover whether the relationship of carbon (C) and nutrients between root and soil would change with mixing ratio. Changes in organic C, nitrogen (N), and phosphorus (P) of root and soil were studied in a 2-year experiment with sole common vetch (Vicia sativa), sole oat (Avena sativa), and their mixtures of different mixing ratios under N, P, and N + P fertilization. Root C, N, and P concentrations decreased with decreasing proportion of common vetch in the grasslands. Nitrogen fertilization significantly improved root N concentration (by 4.5–10.1%), while P fertilization decreased root N concentration (by 10.1–18.4%). The effect of mixing ratio on soil C and nutrients was stimulated by fertilization, although soil C, N, and P contents barely changed with mixing ratio. Mixing and fertilization significantly affected C, N, and P stoichiometric ratios of root and soil (besides soil C:N). Soil C, N, and P contents were strongly positively correlated with root C concentration. The results indicated that increasing legume proportion in the mixture may improve root C and nutrients, which can be stimulated by fertilization. Root quality is closely correlated to soil nutritional status in the mixture. This study further reveals the mechanism how the root is potentially involved in affecting soil fertility and provides a scientific basis on the extensive use of common vetch-oat mixture in the Loess Plateau of China.

Grasses procure key soil nutrients for clovers.

Rhizobial nitrogen fixation in legumes provides spillover benefits to neighbouring plants such as pasture grasses. Generally, it is understood to be unidirectional between plant functional groups, providing a benefit from legumes to grasses. We question whether bidirectional complementarity also exists in terms of exploiting the wider soil nutrient pool. We test this hypothesis using soil cores with their component vegetation assemblages sampled from a hill country pasture in South Island, New Zealand. The soil was deficient in key essential elements: P, S, B, Mo and Ni. Facilitation from grasses to clovers was evident; legume-grass mixtures procured more nutrients from the soil than when either species was growing alone. When grasses and clover grow together in unfertilized grassland, more nitrogen is procured by the plant community, and other limiting plant nutrients in the soil are better exploited. Coexistence with grasses is favourable to clovers in terms of soil biogeochemistry.

Grass-legume mixtures enhance forage production via the bacterial community

Forage monoculture and grass (Gramineae)-legume mixtures are the two most commonly used planting patterns for establishing farming grasslands, but the effects of these planting patterns on the rhizosphere bacterial community and forage production are still unclear. In this study, we carried out a field experiment on the Tibetan Plateau, and observed that grass-legume mixtures significantly increased forage production over monocultures (P < 0.05). We investigated the effects of these two planting patterns on rhizosphere and bulk soil bacterial communities, and found that the grass-legume mixtures altered the community structure and composition of the grass rhizosphere bacterial community, while the bacterial community of bulk soils remained unchanged. Source tracker analysis demonstrated that 50.77% and 34.72% of the changes in mixture rhizosphere of two gramineous grasses were derived from the legume, illustrating that the legume greatly influenced the grass rhizosphere in grass-legume planting. The molecular ecological network analysis demonstrated that network vulnerability and robustness of the mixtures were significantly higher than that of monoculture, indicating that the grass-legume mixtures provided a favorable condition for microbial interactions. Besides, by using structural equation modeling, it was found that the stability and complexity of the bacterial community network had significant positive correlations with forage production, while the soil physicochemical properties had no significant direct correlations, suggesting the rhizosphere bacterial community played a critical role in enhancing plant growth in grass-legume mixtures. This study provides a new insight into the mechanism behind the enhancement of forage production in the grass-legume mixture planting pattern.

Episodic N2O emissions following tillage of a legume–grass cover crop mixture

Abstract. Nitrogen (N) fertilizer inputs to agricultural soils are a leading cause of nitrous oxide (N2O) emissions. Legume cover crops are an alternative N source that can reduce agricultural N2O emissions compared to fertilizer N. However, our understanding of episodic N2O flux following cover crop incorporation by tillage is limited and has focused on single-species cover crops. Our study explores whether increasing cover crop functional diversity with a legume–grass mixture can reduce pulse emissions of N2O following tillage. In a field experiment, we planted crimson clover (Trifolium incarnatum L.), cereal rye (Secale cereal L.), a clover–rye mixture, and a no-cover control at two field sites with contrasting soil fertility properties in Michigan. We hypothesized that N2O flux following tillage of the cover crops would be lower in the mixture and rye compared to the clover treatment because rye litter can decrease N mineralization rates. We measured N2O for approximately 2 weeks following tillage to capture the first peak in N2O emissions in each site. Across cover crop treatments, the higher-fertility site, CF, had greater cover crop biomass, 2-fold-higher aboveground biomass N, and higher cumulative N2O emissions than the lower-fertility site, KBS (413.4±67.5 vs. 230.8±42.5 g N2O-N ha−1; P=0.004). There was a significant treatment effect on daily emissions at both sites. At CF, N2O fluxes were higher following clover than the control 6 d after tillage. At KBS, fluxes from the mixture were higher than rye 8 and 11 d after tillage. When controlling for soil fertility differences between sites, clover and mixture led to approximately 2-fold-higher N2O emissions compared to rye and fallow treatments. We found partial support for our hypothesis that N2O would be lower following incorporation of the mixture than clover. However, treatment patterns differed by site, suggesting that interactions between cover crop functional types and background soil fertility influence N2O emissions during cover crop decomposition.

ZMIANY WĘGLOWODANÓW W MIESZANKACH MOTYLKOWO-TRAWIASTYCH POD WPŁYWEM PODŁOŻA POPIECZARKOWEGO I GNOJOWICY BYDLĘCEJ

The aim of the research was to assess the effect of mushroom substrate and slurry on the content of structural and non-structural carbohydrates in hybrid alfalfa mixtures with grasses. The three-year research was conducted in an experimental field between 2013 and 2015, with the following variables: (1) spent mushroom substrate (SMS) and cow slurry (CS), applied in different combinations; (2) three legume grass mixtures: orchard grass, perennial ryegrass, hybrid alfalfa (M1); orchard grass, hybrid alfalfa (M2); perennial ryegrass, hybrid alfalfa (M3). In each growing season, the mixtures were harvested three times. Plant material was used to determine dry matter content and the content of neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent lignin (ADL), cellulose, hemicellulose, lignin, total protein, crude ash, and crude fat by near infrared spectroscopy (NIRS), using the NIRFlex N-500 spectrometer and ready-to-use INGOT® calibration applications. Generally, mushroom substrate applied on its own increased the amounts of cellulose and hemicellulose in legume grass mixtures more than slurry. The most cellulose, the least hemicelluloses, and the highest degree of lignification were recorded in the mixture of ryegrass with alfalfa, while the degree of lignification was the smallest in the forage of alfalfa and orchard grass, which also contained the least cellulose but the most hemicellulose. On average, the highest amount of cellulose was in the biomass of the first harvest and the least in the third.

Mixture Composition Influenced the Biomass Yield and Nutritional Quality of Legume–Grass Pastures

A two-year field experiment was conducted to address the effects of mixture composition and legume-grass seeding ratio on the biomass yield and nutritional quality of legume–grass mixtures. Alfalfa (Medicago sativa L.), white clover (Trifolium repens L.), red clover (Trifolium pratense L.), orchardgrass (Dactylis glomerata L.), perennial ryegrass (Lolium perenne L.), and tall fescue (Festuca arundinacea Schreb.) were selected as plant materials. A total of seven legume–grass mixtures (A1: white clover, orchardgrass, and tall fescue; A2: alfalfa, orchardgrass, and tall fescue; B1: alfalfa, white clover, orchardgrass, and tall fescue; B2: red clover, white clover, orchardgrass, and tall fescue; C1: alfalfa, white clover, orchardgrass, tall fescue, and perennial ryegrass; C2: red clover, white clover, orchardgrass, tall fescue, and perennial ryegrass; and D: alfalfa, red clover, white clover, orchardgrass, tall fescue, and perennial ryegrass) were sown in two legume-grass seeding ratios (L:G) of 4:6 and 5:5. The results showed that A2 produced a higher two-year average biomass yield (14.20 t/ha) in L:G of 4:6 than that of other mixtures. The grasses biomass yield proportion decreased while legume biomass yield proportion increased with prolonged establishment time. A2 showed a higher crude protein yield (2.5 t/ha) in L:G of 4:6. C2 and A1 showed lower neutral detergent fiber (4.6 t/ha) and acid detergent fiber (2.8 t/ha) yields in L:G 5:5, while diverse mixtures showed higher water-soluble carbohydrate yields. Overall, A2 showed a relative feed value of 146.50 in L:G of 4:6, indicating that it has not only produced the higher biomass yield but also had a better nutritional quality.

Evaluation of dry matter accumulation and competition indices of grass-legume mixtures in the semi-arid Kano Nigeria

An experiment was conducted from April to September 2018 at Bayero University Kano, to determine the nature of competition between Sorghum almum (Columbus grass) and three forage legumes namely Cajanus cajan (pigeon pea), Lablab purpureus (lablab) and Mucuna pruriens (velvet bean) on the basis of dry matter accumulation and competition indices. The treatments were (Sorghum almum sole, three legumes sole and mixtures of grass with legumes at 50:50 replicated in four blocks in randomized complete block design. Seeds of grass and legumes were sown in 3.5m *2m plots. The results showed that sole lablab produced higher (ρ &lt;0.05) cumulative total dry matter (42.07 t ha-1) than sole grass, monoculture of other legumes and mixtures. The cumulative total plant biomass and mean relative yield total of mixtures were not significantly different. Sorghum-Mucuna mixture with mean relative yield total value (1.11) appeared to be more advantageous in terms of efficient resource sharing than other mixtures. Sorghum-Mucuna mixture was recommended as the most compatible combination.

Fallow replacement cover crops impact soil water and nitrogen dynamics in a semi-arid sub-tropical environment

Conventional dryland cropping systems rely upon frequent and lengthy fallow periods to conserve soil water and mineral nitrogen to stabilize crop production. However, this is associated with depletion of soil organic matter and decreased fallow efficiency. Intensifying cropping systems by planting cover crops has been touted as a means to stem soil organic matter loss and improve fallow efficiency. We investigated whether the manipulation of cover crop functional trait diversity and sowing proportions (utilizing Poaceae, Fabaceae, and Brassicaceae) could provide complementary functions that improve soil water and mineral N management during fallow. Grass-legume mixtures represented the best compromise between biomass production (> 4000 kg DM ha˗1), N retention (142 kg N ha˗1), N supply via biological N fixation (35 kg N ha˗1) and maintained an additional 70 mm of water at the end of fallow period. Regardless of functional trait type, cover crops increased N retention but maintained similar soil mineral N content at the end of fallow period. However, soil water effects were functional trait-specific, and there were significant soil water deficits with brassica-dominated cover crops. Soil water accumulation post cover crop termination was significantly higher in cover crops compared with conventional fallows, but the overall fallow efficiency was higher in the conventional fallow. This study demonstrates that cover crops are not universally beneficial, and careful selection of cover crop functional traits in mixtures could enhance fallow soil water and N management in semi-arid sub-tropical drylands.

Effect of pit and plastic bag methods and some additives on chemical composition of grass-legume mixture silages

This study was conducted at the College of Agricultural Engineering Sciences, the experimental field of the University of Sulaimani, during the growing season of 2012 – 2013. The experiment used two methods of making silage (pit method and plastic/ bag method) by making 18 pits with 100×80×100 cm, and 18 plasticbags sized 22 litter. Each silos contained three different forage types: grasses include whole barley and oat; alfalfa as legume and mixture. Those material were treated with two additives of sugar and molasses;solutions at a rate of 1:10; additives were used to improve silage preservation.The factorial design with a complete randomized block design (CRBD) experiment with three replications were used to analysis this study.Themostimportantresults indicatedthat the highest carbohydrates, ash, crude fat, crude fiber and moisture contents of 15.299, 8.580, 2.966, 18.399, and 70.536 % respectively, were achieved by using plastic bags method. The result showed that the highest carbohydrate content of 16.623% was achieved by using plastic methodwith grasses. However, the highest crude protein content of 22.037% was achieved by using pits with plant mixture and sugar. The highest pH value of 5.527 was recorded by the interaction among pits, plant mixture, and molasses. The highest dry matter content of 36.65% of was recorded by the interaction among plastic, grasses and sugar.The maximum carbohydrates content of 15.693% was achieved by using grasses, while legumes gave the highest contents of ash, crude fat, crude protein and dry matter. From the results of this study, it can be concluded that the method of using plastic bags was significant than pits method, the pits method with a mixture of (grasses and legumes) withmolasses produced maximum crude fiber, moisture, crude fat, and dry matter contents.

Biomass yield, yield stability and soil carbon and nitrogen content under cropping systems destined for biorefineries

Sustainable agriculture should aim to increase biomass yield and yield stability, while protecting soil carbon (C) and nitrogen (N) content. However, few studies have concurrently explored changes in biomass yield, yield stability and soil C and N content under different cropping systems targeting biorefinery. In this study, 10 different cropping systems were simultaneously investigated from 2012 to 2017 in central Denmark on a loamy sand soil, including (1) two continuous monocultures of annual crops, (2) one optimized crop rotation, (3) five intensively fertilized perennial grasses, and (4) two grass-legume mixtures without nitrogen (N) fertilization. Our results showed that biomass yield and yield stability differed highly across the cropping systems, highlighting crop-specific characteristics. Of the 10 cropping systems, tall fescue significantly increased soil C and N content at 0–20 cm depth, while sustaining high biomass yield and yield stability. There was no clear relationship between biomass yield, yield stability and changes in soil C and N content, challenging some recent findings on the conflicts between increasing biomass yield and protecting soil C and N content. Indeed, the lack of relationships suggest that there is considerable potential to increase biomass yield and yield stability without compromising soil C and N content through selecting proper cropping systems and managements. Altogether, our results underscore how crop-specific documentation of biomass yield, yield stability and changes in soil C and N content on the same experimental platform can advance the understanding of sustainable agriculture for biorefineries, although long-term continuous observations are still required to better clarify the relations between them.

Improvement of degraded hayfelds in the forest-steppe of the Priobye region

The authors presented the results of research in 2012-2016 on the improvement of degraded hayfields with the sowing of perennial legume grass mixture at different methods of turf cultivation. The work aims to determine the most effective methods of cultivation of the turf of degraded hayfields, contributing to higher yields and quality of the resulting fodder. The highest content of perennial legumes in the herbage was noted in the variant with radical improvement of degraded hayfield (ploughing + discing) - 88 %, in the variant with milling - 80, discing - 70 %. The variant with radical improvement of the degraded hayfield (ploughing + discing) obtained the highest yield - 17.3 green and 3.64 t/ha - dry mass, which exceeds the yield of the control variant by 3.6 times. When carrying out radical improvement of degraded hayfields yield of fodder units was 1740, the number of digestible proteins per 1 fodder unit 140 g. These indicators during turf disking were 1550 fodder unit and 135 g, respectively. During strip seeding of perennial leguminous grasses (meadow clover + alfalfa) the variant with a width of the cultivated strip of 60 cm was selected. The yield of fodder units was 1610, the amount of digestible protein per 1 fodder unit - 120 g. In the control variant the yield of fodder units was 380, the amount of digestible protein per 1 fodder unit - 85 g. Strip-seeding of perennial leguminous grasses was the most cost-effective method of improving degraded hayfields in the Priobye forest-steppe. Net income in variants with strip-seeding of perennial leguminous grasses was 3751-4278 rubles/ha, profitability level - 71- 87%. In the variant with radical improvement of the degraded hayfield (ploughing + discing) these indicators are lower - 3959 rubles/ha and 57 % accordingly.

Improving insect conservation values of agri-environment schemes through diversified seed mixtures

To counteract ongoing biodiversity declines, many European countries have implemented agri-environment schemes (AES) such as ecological focus areas (EFAs), the efficiency of which is often questioned due to low levels of habitat quality. We established new grasslands (NG) using a more diverse seed mixture specifically adapted to mimic low-intensity meadows occurring in our study region in Lower Austria. We compared abundance, species richness, species assemblages and β diversity of solitary bees, bumblebees, syrphids, butterflies, orthopterans, true bugs and cicadas in currently subsidized legume-grass mixtures targeted at supporting pollinators (SG), old grasslands (OG) and NG over a two-year period. Bees, bumblebees and syrphids clearly profited from NG in terms of abundance and species richness, while SG were significantly less attractive. Butterflies were most abundant in OG and significantly less attracted to both SG and NG. True bugs were particularly attracted to NG and SG. However, we did not find any preference in cicadas. Orthopteran species richness was similar in all three types, but individual numbers were significantly lower in NG than in OG. OG and NG supported highly distinctive species assemblages. For solitary bees, syrphids, true bugs and cicadas distinctiveness of sites (β diversity) was more decisive for overall diversity than local diversity. We urge policy makers to put more effort into the establishment of EFAs by using high quality seed mixtures of regionally adapted species and increased plant diversity. Furthermore, preserving permanent grasslands, which support different sets of insect assemblages, should be focused as well to maximize biological conservation value.

THE USE OF SOIL MICROORGANISMS AND HIGHER PLANTS IN THE NEUTRALIZATION OF INDUSTRIAL WASTE IN THE METALLURGICAL, ENERGY AND COAL MINING INDUSTRIES

The self-overgrowth of industrial dumps and tailings of waste from the metallurgical enterprises, energy facilities and coal mining industry is impossible due to the high phytotoxicity of the stored waste. They are dangerous sources of environmental pollution and negative impact on public health. The results of the field experiments on the biological reclamation of the tailings of the Abagur sinter plant, the Baidayevsky coal mine and the Tom-Usinsk State District Power Plant, where the poplar clones obtained from the Botanical Garden of the Siberian Branch of the Russian Academy of Sciences (Novosibirsk), a legume-grass mixture of perennial grasses consisting of hybrid clover and awnless rump served as a plant material. As a soil improver, the wastewater (wastewater sludge WWS) from treatment plants of the city of Novokuznetsk were used. The microbiological fertilizer “BakSib” containing spore-forming bacteria served as a source of the soil microorganisms. The combined use of WWS and the bacterial preparation “BakSib” showed high efficiency in ensuring the survival rate of the cloned poplars, which varied from 70 to 90%. It has been established that the use of bacterial preparations and WWS for the reclamation of technogenically disturbed territories reduces the adverse impact of limiting environmental factors by increasing the water supply and introducing nutritional components into the surface root layer of poplars, hybrid clover and awnless brome. In the reclaimed areas, the moisture content of the substrate was recorded from 5.1 to 14.7%, while the moisture index was 13%.

Effect of Silicon-Containing Fertilizers on the Nutritional Value of Grass–Legume Mixtures on Temporary Grasslands

The study was conducted to evaluate the influence of silicon application on the botanical composition of grass–legume mixtures as well as the nutritional value of individual species and mixtures. The two-factor field experiment was established in a split-block arrangement. The two grass–legume mixtures, consisting of Dactylis glomerata, Festulolium braunii and Trifolium pratense or Medicago x varia and grass mixture—Dactylis glomerata, Festulolium braunii and Lolium perenne, were sown on arable land. Silicon foliar and mineral NPK fertilization was applied in three variants: NPK (non-Si-fertilized), NPK+Si (Herbagreen), NPK+Si (Optysil). Changes in the botanical composition in the sward of mixtures during the study period were influenced by the competitiveness of individual plants and weather conditions, whereas the effect of foliar fertilization with silicon was only slightly marked. The nutritional value of individual species of grasses and legumes varied over the years and also depended on the application of silicon. The greatest content of crude protein (CP), irrespective of the species and variant of silicon fertilization, was noticed in years with no drought. Our research confirmed the beneficial effect of silicon fertilization, independent of weather conditions, on the CP content and on the reduction of crude fibre (CF), neutral detergent fibre (NDF) and acid detergent fibre (ADF) in plants, especially when Herbagreen was applied. The nutritional value of the mixtures under applied silicon fertilization depended on botanical composition. In the conditions of low rainfall, a large share of F. braunii and an approximately 20% contribution of T. pratense resulted in a higher content of CP. These results may be used in the fertilization practices of temporary grassland for enhancing nutritional value, especially crude protein content, and on the reduction of fibre in the sward.

Plant Diversity, Functional Group Composition and Legumes Effects versus Fertilisation on the Yield and Forage Quality

Elevating plant diversity and functional group composition amount in the swards may contribute to lower N fertiliser use. The excessive use of fertilisers in agriculture is one of the causes of environmental pollution issues. We investigated the effects of plant diversity, functional community composition, and fertilisation on the dry matter yield and its quality at the Lithuanian Research Centre for Agriculture and Forestry, Central Lithuania. The study aimed to determine the productivity potential of single-species and multi-species swards with three, four, six, and eight plant species in the mixtures including four grasses and four legumes. Two experimental backgrounds were used with N0 and N150 kg ha−1 yr−1 for all treatments. In the two-year experiment manipulating species richness and functional group diversity had a positive effect on the dry matter yield and produced better quality of the forage when compared with single-species swards. Crude protein in the forage of grass–legume mixtures was significantly greater than for grass monocultures. Investigating fertilisation background was a concern; it had a positive effect on the single-species sward yield but decreased the yield of multi-species swards.

Grass–Legume Mixtures Show Potential to Increase Above- and Belowground Biomass Production for Andean Forage-Based Fallows

Soils of the Andean highlands are under threat from cropping system intensification. Improved forage-based fallows offer great promise to address this issue, but research is needed to better understand the potential of species mixtures vs. monocultures to support multiple farmer objectives, especially forage production and soil conservation. We used a pot study to quantify above- and belowground biomass production as well as the total N uptake of grass–legume pairs between five grasses: (1) oat (Avena sativa), (2) ryegrass (Lolium multiflorum), (3) festulolium (Lolium × Festuca genera), (4) brome grass (Bromus catharticus), and (5) orchard grass (Dactylis glomerata), and four legumes: (1) vetch (Vicia dasycarpa), (2) red clover (Trifolium pratense), (3) black medic (Medicago lupulina), and (4) alfalfa (Medicago sativa) relative to the performance of each species in monoculture within two soils from the central Peruvian Andes. Grass–legume bicultures demonstrated significant overyielding, producing 65% and 28% more total dry biomass and total N uptake on average than monocultures. Aboveground biomass of bicultures was significantly influenced by the species of legume present, while belowground biomass was more affected by the grass species in the mixture. When evaluating the growth of each species separately, our findings indicate that overyielding was driven more by the enhanced growth of grasses relative to legumes. Our findings indicate that combining key functional groups (e.g., grass and legume, annual and perennial) offers great promise for developing improved fallows for supporting soil health and productivity in Andean agroecosystems.

Short‐term impacts of cover crops in maritime potato (Solanum tuberosum) systems

AbstractCover cropping is a soil conservation practice widely investigated in agronomic crops, but less is known about cover crop implications in specialty cropping systems, particularly in a high disturbance system like potato (Solanum tuberosum L.). Brassica cover crops are popular in eastern Washington potato production, but brassica seed crop production in western Washington presents issues with use of brassica cover crops in the region's fresh‐market potato systems. To identify winter cover crops compatible with regional restrictions and climatic challenges in western Washington potato systems, trials including a no‐cover control, eight single species (including brassicas, grasses, and legumes), and a grass–legume mixture were conducted in Mount Vernon, WA, in 2018–2019 and 2019–2020. We examined cover crop and weed biomass production, potato yield and quality, and short‐term soil health impacts by measuring permanganate oxidizable carbon (POXC) and inorganic nitrogen before cover crop incorporation and at midseason. Cover crop biomass and weed suppression varied by year, with annual ryegrass (Lolium multiflorum Lam.) producing the most biomass in both years despite poorer weather conditions and reduced cover crop biomass in other treatments in 2020, making it a good cover crop candidate for western Washington. Both POXC and inorganic nitrogen were greater at midseason but did not vary among cover crop treatments, suggesting that temporal variation influences POXC and inorganic nitrogen more than a single winter of cover crops. Potato yield and tuber wireworm damage varied by year, but not across cover crop treatments, and tuber symptoms resembling black scurf did not vary by year nor treatment.