Grass Legume Research Articles

Hyperspectral imaging predicts yield and nitrogen content in grass–legume polycultures

Hyperspectral imaging predicts yield and nitrogen content in grass–legume polycultures

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.

Comparative Analysis of the Sensitivity of SAR Data in C and L Bands for the Detection of Irrigation Events

Comprehensive knowledge about irrigation timing is crucial for water resource management. This paper presents a comparative analysis between C- and L-band Synthetic Aperture Radar (SAR) data for the detection of irrigation events. The analysis was performed using C-band time series data derived from the Sentinel-1 (S1) satellite and two L-band images from the PALSAR-2 (ALOS-2) sensor acquired over irrigated grassland plots in the Crau plain of southeast France. The S1 C-band time series was first analyzed as a function of rainfall and irrigation events. The backscattering coefficients in both the L and C bands were then compared to the time difference between the date of the acquired SAR image and the date of the last irrigation event occurring before the SAR acquisition (Δt). Sensitivity analysis was performed for 2 classes of the Normalized Difference Vegetation Index (NDVI ≤0.7 and NDVI >0.7). The main results showed that when the vegetation is moderately developed (NDVI ≤0.7), the C-band temporal variation remains sensitive to the soil moisture dynamics and the irrigation events could be detected. The C-VV signal decreases due to the drying out of the soil when the time difference between the S1 image and irrigation event increases. For well-developed vegetation cover (NDVI >0.7), the C-band sensitivity to irrigation events becomes dependent on the crop type. For well-developed Gramineae grass with longs stalks and seedheads, the C band shows no correlation with Δt due to the absence of the soil contribution in the backscattered signal, contrary to the legume grass type, where the C band shows a good correspondence between C-VV and Δt for NDVI > 0.7. In contrast, analysis of the L-band backscattering coefficient shows that the L band remains sensitive to the soil moisture regardless of the vegetation cover development and the vegetation characteristics, thus being more suitable for irrigation detection than the C band. The L-HH signal over Gramineae grass or legume grass types shows the same decreasing pattern with the increase in Δt, regardless of the NDVI-values, presenting a decrease in soil moisture with time and thus high sensitivity of the radar signal to soil parameters. Finally, the co-polarizations for both the C and L bands (L-HH and C-VV) tend to be more adequate for irrigation detection than the HV cross-polarization, as they show higher sensitivity to soil moisture values.

C and N stocks in silvopastoral systems with high and low tree diversity: Evidence from a twenty-two year old field study

This paper aimed to quantify the C and N stocks and the natural abundancy of 13C (δ13C) in organic matter fractions of soil, as well as soil labile C, in a long-term experiment (1997–2019) on silvopastoral systems (SSP) with low and high tree diversity in the Mata Atlântica biome. Disturbed and undisturbed soil samples were collected in transects that were perpendicular to the tree rows every five meters (0, 5, 10, and 15 m of distance), at depths of: 0.0–0.10, 0.10–0.30. 0.30–0.60, 0.60–1.0 m. Litterfall, root density, total organic C and N content, δ13C values for particulate organic matter (POM) fractions as well as mineral-associated organic matter (MAOM) and soil labile C, whilst stocks were calculated afterwards. Litterfall production was higher in the high diversity SSP for all distances, except for 5 m from the tree row. In contrast to litterfall, higher root density was observed for the longest tree distances (15 m) in the low diversity system. The high tree diversity SSP increased TOC stocks in the top soil layer (0.0–0.10 m, distances of 0 and 10 m) only and C-MAOM stocks in the surface (0.0–0.10 m, 10 m distance) and subsurface (0.10–0.30 m, 0 m distance). In contrast, total N stocks or stocks associated with MAOM and POM were higher in the high tree diversity system. The increases were of 37, 36 and 63%, respectively, for total N, N-MAOM, and N-POM up to 1 m depth. The smallest δ13C values found close to the tree row (0 and 5 m distances), especially in the high diversity system, indicate the influence organic residue from leguminous tree species, whilst the C4 grass held the highest contribution at the 15 m distance, also in the high diversity system. In general, the high diversity tree silvopastoral system has shown potential at storing most C in the 0.0–0.10 m soil layers only and N up to 1 m depth. Results showed very little shift in total C stocks, but the increased N stocks with the inclusion the legumes trees, which is reflected in a lower C:N ratio of the SOM. The silvopastoral system containing signal grass both legumes trees can be looked at as a viable strategy towards sustaining existing soil C stocks, whilst increasing N stocks and SOM quality.

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.

Effect of substrate properties and phosphorus supply on facilitating the uptake of rare earth elements (REE) in mixed culture cropping systems of Hordeum vulgare, Lupinus albus and Lupinus angustifolius

This study presents how phosphate (P) availability and intercropping may influence the migration of rare earth elements (REEs) in legume–grass associations. In a replacement model, Hordeum vulgare was intercropped with 11% Lupinus albus and 11% Lupinus angustifolius. They were cultivated on two substrates, A (pH = 7.8) and B (pH = 6.6), and treated with 1.5 g P m−2 or 3 g P m−2. Simultaneously, a greenhouse experiment was conducted to quantify carboxylate release. There, one group of L. albus and L. angustifolius was supplied with either 200 µmol L-1 P or 20 µmol L-1 P. L. albus released higher amounts of carboxylates at low P supply than L. angustifolius, while L. angustifolius showed the opposite response. Plants cultivated on substrate B accumulated substantially higher amounts of nutrients and REE, compared to substrate A. Higher P supply did not influence the leaf and stem P concentrations of H. vulgare. Addition of P decreased REE accumulation in barley monocultures on alkaline soil A. However, when H. vulgare was cultivated in mixed culture with L. angustifolius on alkaline substrate A with high P supply, the accumulation of REE in H. vulgare significantly increased. Conversely, on acidic substrate B, intercropping with L. albus decreased REE accumulation in H. vulgare. Our findings suggest a predominant effect of soil properties on the soil–plant transfer of REEs. However, in plant communities and within a certain soil environment, interspecific root interactions determined by species-specific strategies related to P acquisition in concert with the plant’s nutrient supply impact REE fluxes between neighbouring plants.

Economic and energy efficiency of growing legume grasses

Economic and energy efficiency of growing legume grasses

Приготовление качественных ферментируемых кормов из бобовых трав

The current study presents the results on evaluation the preservative efficiency of domestic biological preparations, based on enzymes, at the ensiling and haylage preparation of high-protein leguminous grasses. High-yielding varieties of alfalfa, red clover and fodder galega (Galega orientalis Lam.), that were developed in Williams Research Center of Forage Production & Agroecology were used as plant raw material. Plants were harvested in the optimal vegetation phases. The effect of the new biological preparations on safety and quality of fermented feeds in terms of organoleptic and biochemical parameters, the effect on the digestibility of nutrients and their bioconversion into the valuable animal products were studied in the laboratory and scientific-production conditions. The effective methods of preparation the qualitative feeds with high protein and energy content of legume grasses, were suggested on the base the obtained results. Fermented feeds with complex of enzyme-bacterial preparations are suitable for highly productive dairy and beef cattle.

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.

Tamani grass-legume intercropping can improve productivity and composition of fodder destined to haylage or hay

ABSTRACT: This research evaluated the biomass productivity and nutritional value of the haylage and hay from intercropping between Tamani grass and different legume species. For the productive characteristics of the different intercrops, we adopted a randomized block design, for evaluation of the combination of intercropping and conservation technic we used 5 x 2 factorial scheme (five intercrops and two types of conservation techniques). The treatments were Tamani grass as monoculture, and the intercrops of Tamani grass with crotalaria, soybean, cowpea, or pigeon pea. The conservation techniques were haylage (520 g/kg of DM) and hay (870 g/kg of DM). Plants were sown in alternate rows, with 45 cm of spacing between the rows. The parameters evaluated were grass and legume biomass production, canopy height, and haylage and hay chemical composition, and in vitro dry matter digestibility (ivDMD). There were no differences in the total biomass production between the intercrops and TA grass monoculture. The treatments intercropped with cowpea and soybean had the highest legume participation in the mixture, promoting an increase in crude protein and ivDMD content of haylage and hay. Haylage and hay had the same chemical composition, although haylage had higher ivDMD than hay. We concluded that intercropping Tamani grass with soybeans or cowpea maintained total biomass productivity and improved the nutritional value of haylage and hay.

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.

Evaluating nondestructive forage sampling techniques in alfalfa–bermudagrass mixtures in the southeastern United States

AbstractThe increased use of legume–grass mixtures in grazing systems has resulted in the need for more accurate forage estimation techniques for these diverse mixtures. In mixed stands, variations in species composition and canopy density make the estimation of herbage mass (HM) challenging. Three nondestructive sampling techniques [a rising plate meter (RPM), a pasture ruler, and digital image analysis] were compared with traditional botanical hand separation to determine their effectiveness in predicting HM in bermudagrass [Cynodon dactylon (L.) Pers.] and alfalfa (Medicago sativa L.) pastures when harvested to a 1‐ or 4‐inch stubble height. All models calibrated to forages harvested to 1 inch failed to meet the formal assumptions of the F‐test. The height and RPM were moderately successful at predicting HM when calibrated to samples harvested to 4 inches. However, the models were unable to predict HM above 4,000 lb acre−1 in their current form. Future research in alfalfa–bermudagrass mixtures should focus on isolating how HM changes within the canopy and increase the sample area used to collect the calibration data.

PRODUCTIVITY AND QUALITY OF THE HERBAGE OF THE FIRST YEAR OF LIFE OF PERENNIAL PASTURE GRASS MIXTURES DEPENDING ON THE SPECIES COMPOSITION IN THE CONDITIONS OF THE HILL-PLAIN ZONE OF NORTHERN KAZAKHSTAN

The purpose of the study is to develop a multi–year near-village pasture conveyor and increase the productivity and nutritional value of grass mixtures. In the process of conducting the current research, the methods of field experiments generally accepted in agronomy were used, laboratory studies were conducted in an accredited laboratory according to established methods and standards on modern equipment; the objects of research are various types of perennial bluegrass and legume grasses cultivated in grass mixtures. Results and practical significance. The given paper presents an analysis of the laboratory studies on the chemical composition and nutritional value of perennial grasses of the first year of life in mixtures proposed for use in the creation of near-village pastures in the conditions of the hill -plain zone of Northern Kazakhstan. Chemical analysis of plant samples was carried out in the accredited agrochemical laboratory of «AgroComplexExpert» LLP (village of Zhaksy).

Methods for pre-sowing treatment of legume grass seeds to improve their sowing properties

In recent years, more and more areas of agricultural land have been cultivated with the valuable non-traditional fodder crop galega, which perfectly combines high productivity with excellent fodder values and sustainable seed production, rationally uses agro-climatic conditions of the zone and increases soil fertility, and is valuable as a forecrop and a honey-bearing plant. The sowing material of the Eastern galega contains 50…95% of seeds with a hard shell. Seed hardness is explained by impermeability of seed shells to water and air. To increase the germinating capacity of seeds and reduce the norm of galega seeds sowing to 2.0 million/ha the sowing material of perennial leguminous fodder crop - Eastern galega should undergo pre-sowing treatment - scarification and seed inoculation. The construction and working principle of the developed technical means are presented: a scarifier SS-0,5 and an inoculator IS-1,0. The developed scarifier and inoculator of seeds of leguminous crops qualitatively perform the technological process of pre-sowing treatment of Eastern galega seeds. At optimum feed of 0.5 t/h and 1.0 t/h, the quality indicator of Eastern galega seed scarifying reaches 98.8 %, the completeness of inoculator treatment reaches 99.8 %, without seed damage that meets the agrotechnical requirements.

Aspects of the determining the sowing properties of seeds of perennial grasses express method effectiveness in comparison with domestic and international rules

Purpose. To theoretically substantiate the methodology for the accelerated determination of the sowing qualities (express method) of seeds of leguminous and cereal grasses, in particular germination capacity, the amount of hard seeds and viability in comparison with the defining those indicators according to the State standard of Ukraine (SStU 4138-2002), international methodology (ISTA – International seed testing association). Methods. Quantitative, laboratory, mathematical-statistical, observation, comparison, analysis and synthesis. Results. Determination of sowing qualities (germination energy, germination rate, amount of hard seeds) of forage crops according to the methods of SStU 4138-2002; ISTA (international rules for the analysis of seeds) and the express method of accelerated determination, showed the high efficiency and effectiveness of the latter (improved method of swelling seeds of leguminous grasses and preparatory caving of films and swelling of seeds of cereal grasses), which can be used in production conditions to obtain objective information on the sowing properties of seeds of the formed harvest. Conclusions. The express method can be used to determine the viability of legume grass seeds within 3-4 hours by establishing the difference between the number of live and dead seeds. The data obtained are close to the germination rates when analyzing seeds according to the SStU 4138-2002 and ISTA methods and make up 90-95; 93-95; 92-95% respectively. Germination of seeds of cereal grasses using the caryopsis method allows determining the viability of seeds on the 2nd-5th day in species with high germination energy (Bromus inermis, different types of Lolium perenne) and 7th-10th day in species with slow germination (Festuca rubra L). Seed germination of these species according to the express method was 84- 92%, while according to the SStU 4138-2002 and ISTA methods it made up 91-94; 90-96%, and the analysis was carried out on the 10th and 21st day.

Люцерна — высокобелковая кормовая культура

The results of selection studies conducted at the Central Experimental Base of the V.R. Williams in the Non-Chernozem Zone of the Russian Federation are presented. Brief data on promising varieties of alfalfa created in the department of alfalfa breeding for the yield of green and dry mass, crude protein and other indicators are presented. Alfalfa varieties of a new generation adapted to local soil and climatic conditions have been created. Alfalfa is one of the best legume grasses for the preparation of high-protein feed. Alfalfa is a culture that is characterized by ecological plasticity, longevity, capable in many regions of Russia to solve the problem of eliminating the deficiency of vegetable protein in the diets of farm animals. It can be used as a legume component of grass mixtures on pastures and hayfields of the Non-Chernozem zone of Russia. The level of productivity and sustainability of fodder agrophytocenoses is determined by the competitiveness of species and varieties. Alfalfa varieties have a low competitive ability, do not withstand three or four times mowing, quickly fall out of the grass stand. It is known that the use of mineral nitrogen in meadow and field feed production is limited due to high energy costs in the production of nitrogen fertilizers. Therefore, the need for nitrogen in meadows and pastures should be met by legume-cereal grass mixtures, for which it is necessary to create new varieties of legumes, in particular alfalfa variable or hybrid.

Lotus tenuis and Schedonorus arundinaceus co-culture exposed to defoliation and water stress

The present study aimed to investigate the effect of defoliation frequency (low and high) and water stress (excess or deficit) on biomass production, P and N nutrition, and symbiosis with native soil microorganisms on a Lotus tenuis and Schedonorus arundinaceus co-culture in a pot experiment. Combined effects of defoliation frequency and water stress affected plant accumulated shoot biomass. L. tenuis root biomass decreased in response to defoliation and water stress, while S. arundinaceus root biomass was similar between non-defoliated and defoliated plants, at all water levels. Low and high frequencies of defoliation in a waterlogged soil can be considered the most stressful scenario for L. tenuis and S. arundinaceus co-culture. Colonization of arbuscular mycorrhizal fungi in L. tenuis roots and dark septate endophytes colonization in S. arundinaceus roots were affected by both factors, whereas arbuscular mycorrhizal colonization in S. arundinaceus was affected only by water stress. Both plants tolerated defoliation and water stress due to the interaction between the translocation of nutrients and carbon compounds from roots to shoots, and P and N absorption (plus N2 fixation in L. tenuis). Highlights: Both plants tolerated defoliation and water stress due to the interaction between the translocation of nutrients and carbon compounds from roots to shoots, and P and N absorption (plus N2 fixation in tenuis). Low and high frequencies of defoliation in a waterlogged soil can be considered the most stressful scenario for tenuis and S. arundinaceus co-culture. Defoliation frequency increased AM colonization in plant roots under well watered and water deficit conditions. arundinaceus roots were co-colonized by AM fungi and DSE. Promoting the presence of tenuis through low defoliation frequency would improve forage yield and quality with the maintenance of AM symbiosis in legume–grass communities.