Mixture Of Perennial Ryegrass Research Articles

Response of cool‐season turfgrass monocultures and two‐way mixtures to sequential acute drought periods

AbstractTurfgrass seeds are often sold as mixtures of several species to increase the probability of positive responses toward abiotic and biotic stresses, a response to drought being one of these. Several species of turfgrass are already thought to be better suited for drought, such as hard fescue (Festuca brevipila Tracey) and tall fescue [Schedonorus arundinaceus (Schreb.) Dumort]. However, little is known about the benefit of these species in mixtures with drought‐intolerant and/or drought‐avoiding species during drought. Understanding species mixture composition during establishment, before and after drought stress periods, could help develop more resilient mixtures for this stress condition. We compared monocultures and mixtures of hard fescue, Kentucky bluegrass (Poa pratensis L.), and perennial ryegrass (Lolium perenne L.) during sequential short drought and recovery periods in controlled conditions. We observed that the composition of most mixtures remained similar during drought and recovery periods; however, perennial ryegrass was often less prevalent after drought stress. We found that hard fescue monocultures had better green leaf coverage than Kentucky bluegrass and perennial ryegrass during drought stress. However, the presence of hard fescue in mixtures was not an indicator of greater drought tolerance, and variable fluorescence to maximal fluorescence data indicated that hard fescue was just as physiologically stressed as perennial ryegrass and Kentucky bluegrass during the drought periods. These results indicate that while hard fescue seems visually drought tolerant, it is still physiologically stressed and improved drought tolerance could be achieved through focusing on physiological indicators of stress in this species rather than visual indicators.

Lactic Acid Bacteria and Formic Acid Improve Fermentation Quality and Beneficial Predicted Functional Characteristics in Mixed Silage Consisting of Alfalfa and Perennial Ryegrass

The purpose of the present study was to investigate the effect of additives on the fermentation properties of ensiled mixed alfalfa and perennial ryegrass silage in the karst terrain of Southwest China. A mixture of alfalfa and perennial ryegrass was ensiled at a ratio of 3:7 using three experimental treatments: (1) CK (without additives) and distilled water (5 mL kg−1 fresh weight (FW)); (2) FA and formic acid (88%) (5 mL kg−1 FW); and (3) LAB combined with the application of Lactiplantibacillus plantarum and Lentilactobacillus buchneri (2 × 107 cfu/g FW). All samples were packed manually into polyethylene bags, and three polyethylene bags from each treatment were sampled on days 7, 15, and 45. The findings demonstrated that the pH values of all the mixed silages gradually decreased during ensiling. The lactic acid (LA) and acetic acid (AA) contents increased gradually with ensiling time and peaked after 45 days of ensiling. After 45 days of ensiling, the FA and LAB groups effectively preserved the nutrient content of the mixed silage, which presented a reduced neutral detergent fiber and acid detergent fiber content (p < 0.05) and higher water-soluble carbohydrate content (p < 0.05) than the CK group. The fermentation quality of the mixed silages in the FA and LAB groups improved, as indicated by higher (p < 0.05) LA contents and lower (p < 0.05) pH and ammoniacal nitrogen contents after 45 days of ensiling compared to those in the CK group. As fermentation progressed, the abundance of harmful microorganisms (Hafnia obesumbacterium, Enterobacteriaceae, and Sphingomonas) and beneficial microorganisms (Lactiplantibacillus and Lentilactobacillus) decreased and increased, respectively. In addition, compared to those in the CK group, the FA group had higher abundances of “lipid metabolism” and “biosynthesis of antibiotics” and lower abundances of “membrane transport”. Briefly, the results of this study suggest that the incorporation of FA and LAB additives could improve the quality of fermented mixed silage, and that FA is better than LAB. This information is useful for combining forage resources to satisfy the requirements for high-protein feed and for manufacturing ruminant feed annually.

Evaluation of perennial poaceae grasses species and varieties for creating lawns

Under the conditions of the Moscow region, in a field experiment, a comparative assessment of 6 types of perennial grasses and 13 of their varieties was carried out in the lawn mode of use for 12 years. It has been established that in the first year of life, the highest intensity of tillering in the first two to three months was observed in perennial ryegrass, meadow fescue and giant bentgrass. The projective cover of single-species lawns from these species amounted to 92-96% by autumn. In the first year, red fescue was characterized by lower development rates and by the beginning of autumn formed a high-quality lawn with a closed-mosaic structure and 71-79% projective cover, depending on the variety used. The slowest formation of lawns in the year of sowing was noted for meadow bluegrass, which provided projective cover in different varieties from 14 to 60%. The bluegrass lawns reached their maximum density mainly in the third year. The most high-quality lawn with a closed-diffuse composition and 100% projective cover was formed already in the first year when using a grass mixture with the participation of varieties of red fescue, meadow fescue, perennial ryegrass, bent grass, a mixture of meadow fescue, perennial ryegrass and giant bent grass, as well as a mixture of these species with varieties of bluegrass, red fescue and meadow timothy. The best longevity with a high density of shoots and close-diffuse composition with more than 90% annual projective cover for 12 years was distinguished by lawns from red fescue varieties Dipa and Celianna. In polyspecific lawns with the participation of bluegrass meadow, the share of its shoots in the total structure did not exceed 17-38%. Starting from the eighth year, due to the low vegetative mobility of red fescue, there was a consistent increase in the number of bluegrass shoots in the lawn. With intensive constant use of the lawn for sports, the grass mixture with a predominance of up to 90% of bluegrass meadow variety Balin turned out to be the most stable.

The effect of the addition of a companion forage to a perennial ryegrass sward on ewe and lamb performance

Ireland's competitive advantage in sheepmeat production is based on the efficient and cost effective production and utilisation of pasture. The objective of this study was to assess the influence of binary mixtures of perennial ryegrass (Lolium perenne L.) plus a companion forage on ewe and lamb performance at pasture. Five sward mixtures were compared, namely; i) perennial ryegrass (Lolium perenne L.;PRG), ii) PRG plus white clover (Trifolium repens L.;PRG + WC), iii) PRG plus red clover (Trifolium pratense L.;PRG + RC), iv) PRG plus plantain (Plantago lanceolate L.;PRG + Plan) and v) PRG plus chicory (Chicorium intybus L.;PRG + Chic). Five farmlets with one sward treatment assigned to each were established which 23 ewes plus their lambs grazed from March to December for the years 2018 to 2021 inclusive. Farmlets were rotationally grazed, stocked at 11.5 ewes/ha and received 130 kg nitrogen/ha/year. Lambs were weaned on average at 15 weeks of age. Post-weaning a leader-follower grazing system was implemented with lambs grazing ahead of the ewes. Post weaning, lambs were weighed fortnightly and drafted at a live weight of 42 kg in June and increasing by 1 kg per month thereafter to produce a target carcass weight of 20 kg. Results show that lamb lifetime average daily gain (ADG) was greater for lambs grazing all binary sward mixtures relative to grazing PRG. Relative to PRG, lamb lifetime ADG was increased by between 17 g/day (PRG + Plan; P < 0.01) to 31 g/day (PRG + RC, and PRG + Chic; P < 0.001) and subsequently the number of days required to reach slaughter (DTS) was reduced by between 15.8 days (PRG + Plan; P < 0.01) to 28.6 days (PRG + RC; P < 0.001) with the addition of a companion forage. As a result of lower DTS, the average total number of anthelmintic treatments administered per lamb was significantly reduced for lambs grazing on all of the binary sward mixtures relative to PRG (P < 0.001). Scanned litter size and ewe milk yield were similar across all sward types as were ewe body weight (BW) and body condition score (BCS) from mating up until 6 weeks post-lambing (P > 0.05). Of the ewes retained from one production year to the next, those grazing PRG + WC, PRG + RC and PRG + Plan had a greater BW than those grazing PRG at the second mating event (P < 0.05), whilst, PRG + RC, PRG + Plan and PRG + Chic ewes had a greater BCS than PRG ewes (P < 0.05). These results suggest the suitability of binary sward mixtures under an intensive sheep grazing system to improve ewe and lamb performance at pasture.

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.

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.

Nitrogen effects on species’ contributions to grazed pasture mixtures under nitrogen loss and application restrictions

New regulations to the use of N fertiliser will impact on seed mixture decisions for new pastures. To help inform these decisions, the effects of N on species and species interactions in pasture mixtures were examined. Ten mixtures of perennial ryegrass (PR), white clover (WC) and plantain (P) were sown on 31 March 2017 and grown ±N fertiliser (275 kg/ha in Year 1 reduced to 200 kg N/ha/year) under grazed and irrigated conditions at Lincoln University. After 4 years, an equi-proportional mixture of PR and WC (based on seed count) optimised average total yield (TY), weed yield (WY), metabolisable energy (ME) and crude protein (CP) regardless of N level. The optimal sowing rate was 12.2 kg PR and 7.0 kg WC/ha. Average TY of the optimal mixture was 20.5 t DM/ha/year with 4% WY, 11 MJ/kg DM ME and 21% CP. Pasture yield and quality responded to change in species proportions away from the optimal mixture, including the addition of P. The magnitude of the TY and WY responses was greater with than without N fertiliser because the identity effects of PR and P, and the way all three species interacted, depended on N level.

Effect of molasses on fermentation quality of wheat straw ensiled with perennial ryegrass

Context Insufficient supply of silage has limited the development of animal husbandry in Tibet, where natural pasture may not meet requirements. Although wheat (Triticum aestivum L.) straw could be a supplementary forage, it is difficult to ensile. Mixing perennial ryegrass (Lolium perenne L.) and adding molasses may help to facilitate successful ensilage. Aims The objectives were to determine the proper mixing ratios of wheat straw and perennial ryegrass for silage, and to evaluate the effects of different levels of molasses on fermentation quality. Methods In Experiment 1, wheat straw was ensiled without perennial ryegrass or mixed at ratios of 4:1, 3:2 and 2:3 (fresh-weight basis). Fermentation quality was evaluated when the laboratory silos were opened after 7, 14, 30 and 60 days. In Experiment 2, a mixture of wheat straw and perennial ryegrass (2:3) was treated with 0%, 3%, 4% and 5% molasses (fresh-weight basis) and ensiled. Fermentation quality was determined at 7, 14, 30 and 60 days. Key results In Experiment 1, inclusion of perennial ryegrass significantly (P &lt; 0.05) increased lactic acid and water-soluble carbohydrate contents and the lactic acid:acetic acid ratio, and significantly (P &lt; 0.05) decreased pH and contents of ammonia-nitrogen, acetic acid, butyric acid and total volatile fatty acids. The 2:3 mixture of wheat straw ensiled with perennial ryegrass was judged the best, with the highest lactic acid content and lowest pH and butyric acid content (P &lt; 0.05). In Experiment 2, molasses addition significantly (P &lt; 0.05) increased lactic acid, water-soluble carbohydrate and dry matter contents, and significantly (P &lt; 0.05) decreased pH and ammonia-nitrogen content compared with the control. Trace amounts of propionic and butyric acids were observed in all silages. Fermentation quality was similar among all treatments with added molasses. Conclusions Considering the costs of additives, 3% molasses was most suitable for practical application when ensiling wheat straw with perennial ryegrass at an optimum ratio of 2:3. Implications This work may help to inform producers on efficient utilisation of wheat straw for silage making by demonstrating successful ensiling with perennial ryegrass and added molasses.

Plant diversity with species drilled in the same or alternate rows enhanced pasture yield and quality over 4 years

This paper reports on the effects of plant species diversity and sowing method on pasture yield and quality. Nineteen seed mixtures of perennial ryegrass (PR), plantain (Pl), white clover (WC) and red clover (RC) were sown on 26 March 2015 at Lincoln University. Four mixtures of PR, Pl and WC were repeated with species separated in alternate drill rows. Plots were grazed by sheep and irrigated. After 4 years, a mixture with 25% of each species based on seed count – equivalent to 7.5 kg PR, 5.6 kg Pl, 1.9 kg WC and 4.4 kg RC (19.4 kg total seed)/ha – produced an optimal balance of increased total yield (17.44 t DM/ha/yr), weed suppression (0% of total yield), metabolisable energy (11.4 MJ/kg DM) and crude protein (19% of DM). Sowing method had no effect. Plant diversity enhanced pasture production through positive interactions and identity effects among the legumes (WC and RC) and non-legumes (PR and Pl). The strength of interactions between species depended on the identity and relative abundances of the species involved. The diversity effects occurred alongside shifts in species relative abundances over time. This study demonstrated an experimental basis for the evaluation of multi-species pasture mixtures.

Effects of overseeding times on different warm-season turfgrasses: Visual turf quality and some related characteristics

The sustainability of warm-season turfgrass species in winter dormancy is a major concern in Mediterranean ecology. The concept of overseed a lawn has been still new for many developing countries such as Turkey as part of a regular maintenance. Therefore, a 2-year study was conducted at the experimental fields of Ege University, Izmir/Turkey during 2014-2016 years to compare the effects of four different overseeding times (September 15, September 30, October 15 and October 30) on four warm season turfgrass species (Cynodon dactylon cv. SR9554, Cynodon dactylon × Cynodon transvaalensis cv. Tifway-419, Paspalum vaginatum cv. Sea Spray and Zoysia japonica cv. Zenith) by measuring visual turf quality (1-9 score) and some related characteristics as texture (mm), cover (1-9 score), weed infestation (1-9 score) and colour (1-9 score). ‘50% cv. Troya+50% cv. Esquire’ perennial ryegrass (Lolium perenne L.) mixture was used for overseeding in trial. According to results, visual turf quality performance of 6.0 scores and above were obtained from all treatments. We concluded that October 15 should be most suitable time for overseeding applications. Additionally, L. perenne L. can be practiced successfully in Mediterranean region in order to eliminate the concerns of warm-season turfgrasses in the winter dormancy period observed in cold temperatures. Highlights - No gaps were formed in plots and high coverage degrees were maintained during overseeding periods in all treatments. - Homogeneous spring transition was occurred from Lolium perenne L. to warm-season turfgrass species in all overseeding times. - Visual turf quality performance of 6.0 scores and above which is acceptable level were obtained from all overseeding times. - Better results were obtained from overseeding applications on Paspalum vaginatum and Cynodon dactylon × Cynodon transvaalensis. - The different results among the warm-season turfgrass species can provide effective information for future research studies.

Strategies for increased yellow nutsedge (Cyperus esculentus) control in turfgrass with halosulfuron, sulfentrazone, and physical removal

AbstractYellow nutsedge is one of the most widely distributed and troublesome weeds in the world. Field and greenhouse studies were conducted to optimize strategies for increased yellow nutsedge control in turfgrass with halosulfuron and sulfentrazone. In the field study in yellow nutsedge and perennial ryegrass mixture, single or sequential applications (3 wk after initial) of halosulfuron or sulfentrazone were made on June 3, June 23, July 15, or August 5 in 2013, 2014, 2015, and 2016. Percent yellow nutsedge control was rated within the same growing season on September 17 and the following year on June 3 for carryover control. Field and greenhouse studies confirm that sequential applications of halosulfuron with a 3-wk interval resulted in &gt;95% control in a yellow nutsedge–turfgrass mixture. In a greenhouse study, both herbicides reduced yellow nutsedge root and rhizome dry mass from 39% to 98%, reduced number of new tubers and tuber fresh weight from 38% to 100%, and prevented re-emergence. Sequential applications of either herbicide within a 3-wk interval early postemergence is recommended for optimal control. Herbicide application to yellow nutsedge using halosulfuron and sulfentrazone should be made as early as possible postemergence, preferably at the three- to five-leaf stage or 200 to 250 growing degree days (GDD, 10 C base). Mowing can be an effective method to reduce yellow nutsedge growth. Mowing at 7.6 cm weekly reduced yellow nutsedge rhizome dry mass by 55% and number of new tubers formed by 63% in the greenhouse study. Physical removal of yellow nutsedge plants such as hand-pulling can be an effective method to manage yellow nutsedge and is most effective at the three- to five-leaf stage (200 to 250 GDD). End-users can maximize yellow nutsedge control by integrating early herbicide treatments and cultural practices such as mowing and hand-pulling.

Methane Emission and Milk Production from Jersey Cows Grazing Perennial Ryegrass–White Clover and Multispecies Forage Mixtures

Methane is a major constituent of greenhouse gas (GHG) emissions from ruminants, and mitigation strategies are needed to alleviate this negative environmental impact while maintaining the environmental and other benefits of grazing systems. Forages containing plant-specialized metabolites (PSM), particularly condensed tannins, may help reduce enteric methane (CH4) emissions. However, information on in vivo CH4 emissions from cows grazing mixtures that contain bioactive herbs is scarce. Accordingly, this study compared a binary mixture of perennial ryegrass (Lolium perenne) and white clover (Trifolium repens) against a diverse mixture of six additional species, including tannin-rich species like birdsfoot trefoil (Lotus corniculatus) and salad burnet (Sanguisorba minor), in a full-grazing dairy system. Enteric CH4 emissions were measured using the SF6 tracer technique. Cows grazing diverse mixtures increased their energy-corrected milk (ECM) yield by 4% (p &lt; 0.001) compared with binary mixtures. However, CH4 emissions per kg ECM were also 11% greater for the diverse mixtures (p &lt; 0.05). The very high feed quality and milk yield from both mixtures explained the low CH4 emissions recorded relative to the milk output. The addition of forbs did not provide additional benefits at these intensities, as they were maintained in low yield shares throughout.

The agronomic performance of perennial ryegrass varieties evaluated as monocultures and mixtures of varying complexity under animal grazing

Perennial ryegrass varieties are evaluated in monoculture plots, but in practice are typically sown as combinations of three or more varieties. Monoculture performance is used a predictor of mixture performance, but is questionable, particularly for grazing efficiency traits that interact with the grazing animal. Two field experiments were carried out to examine the production, grazing efficiency and nutritive quality traits of varieties sown in monoculture, and their binary, ternary and quaternary mixtures. Both studies contained two diploid and two tetraploid varieties comprising of only Late heading varieties in Study 1 and combinations of Late and Intermediate heading varieties in Study 2, all managed under cattle grazing with 16 grazing events taking place over two years.Synergistic effects, defined as a higher performance above that of the component variety mean (based on their respective component monoculture performance), were observed within some mixtures for certain traits although these rarely exceeded that of the best component monocultures. Performance differences attributable to ploidy in monoculture were expressed in the mixtures but differences in the spread of heading date within a mixture had few effects. Differences in grazing efficiency between varieties were also expressed within mixtures but with no consistent evidence of a synergistic enhancement of the cattle’s willingness or ability to graze sward mixtures more effectively. Mixture performance values were within the range of the component varieties for most traits, indicating that monoculture evaluation can be used as a reliable indicator of the performance of perennial ryegrass mixtures.

Growth dynamics of fast-growing tree species in mixed forestry and agroforestry plantations

In recent years, plantations of fast-growing tree species have emerged as a possible way to meet the increasing demand for biomass for renewable energy in Europe. Agroforestry plantations including fast-growing tree species could be an attractive option because they reduce land competition for biomass and food production while providing forest benefits. Today, the species interactions that determine whether a given mixture will be more productive than the corresponding monocultures are still poorly understood. Our objective was to assess the performance of fast-growing trees, i.e. poplar (Populus nigra × P. deltoides) and alder (Alnus glutinosa), in association with herbaceous species either N2-fixing species (succession alfalfa (Medicago sativa) and clover (Trifolium pratense)) or graminoids (succession of wheat (Triticum aestivum) – triticale (Triticosecale) – temporary grassland consisting of mixtures of perennial ryegrass (Lolium perenne) and fescue (Festuca ovina)), respectively, and in association together. We compared tree growth in mixed stands to growth in the respective tree monocultures. An experimental plantation composed of three blocks including the different treatments was set up in 2014 in northeastern France. In the forest mixture, poplar and alder were planted in alternating rows, and in the agroforestry plots, every second line of trees was replaced by the crops. No fertilizers (of any kind) were used during the experiments. During six growing seasons, tree growth (height and diameter at breast height) was monitored monthly in the agroforestry stands, the forest mixture stand and the two tree monocultures. By the end of 2019, poplar stem height in association with N2-fixing crops (alfalfa, then clover) was higher than in the forest mixture and the monoculture. During the warmest growing season with a marked dry period in June-July (2018), poplar height growth rate in the agroforestry treatment was between three and five times higher than for the poplars in the monoculture and the forest mixture. A facilitation process in the agroforestry plantations could explain this result due to a significant enrichment of the soil in nitrogen by the N2-fixing crops. This result only appeared several years after tree planting, and management actions were necessary in order to control the strong competition between crops and trees during the early stages. In the forest mixture, poplars associated with alders were smaller than in their monoculture, in spite of a stratification of the canopies of the two species. For alders, tree growth did not appear to be affected by either an association with graminoids or with poplar.

The Effect of Spent Mushroom Substrate and Cow Slurry on Sugar Content and Digestibility of Alfalfa Grass Mixtures

The aim of this paper is to evaluate the effect of different doses of spent mushroom substrate and cow slurry on sugar content and digestibility of hybrid alfalfa and grass mixtures. The main factors were different doses of organic material: mushroom substrate and slurry, and the following legume grass mixtures: M1-orchard grass (Dactylis glomerata), perennial ryegrass (Lolium perenne), and hybrid alfalfa (Medicago x varia T. Martyn); M2-orchard grass, hybrid alfalfa; M3-perennial ryegrass, hybrid alfalfa. In each growing season, the mixtures were harvested three times during three years of their full use. Sugar content and dry matter digestibility were determined with near-infrared spectroscopy (NIRS) using the NIRFlex N-500 spectrometer. Of all fertilizer treatments, the application of mushroom substrate at a dose of 20 t·ha−1 in combination with 40 m3 of slurry resulted in the best forage quality with its highest digestibility. In the mixture of perennial ryegrass and hybrid alfalfa increasing doses of mushroom substrate with decreasing doses of slurry lowered soluble sugar content and digestibility.

Effects of expanding functional trait diversity on productivity and stability in cultivar mixtures of perennial ryegrass

Cultivar mixtures can provide a host of beneficial agroecosystem services in annual grain crops; however, it remains unclear whether these same benefits apply to perennial forage cropping systems, or the degree to which beneficial effects depend on the functional trait diversity of the mixtures. We conducted a field experiment across four locations in the Northeast US in which we grew perennial ryegrass cultivar mixtures varying in cultivar number and range of expression of three functional traits (winter hardiness, heading date, and extended growth) and assessed the effects on dry matter yield and inter-annual yield variability. Trait ratings supplied by the seed company were related to observed variation in perennial ryegrass productivity and/or stability at both the individual cultivar and mixture levels. Winter hardiness was associated with greater perennial ryegrass cumulative biomass, and lower interannual stability. In contrast, extended growth was associated with lower cumulative biomass, and both extended growth and later heading date were associated with greater interannual variability. Overall, cultivar richness was negatively associated with perennial ryegrass biomass and stability; however, the best performing mixtures performed as well as the recommended cultivar for the region. When comparing mixtures with equal cultivar richness, functional trait diversity measured as the additive trait range—the summed range of the three traits associated with the cultivars in that mixture—was positively associated with biomass production and over-yielding, but not interannual variability. Cultivar mixtures of perennial ryegrass can lead to improved forage production when specific functional traits are optimized within mixtures. Our results support the growing understanding that efforts to ecologically intensify agriculture through enhancement of crop diversity are more likely to succeed when they explicitly consider the functional traits of the crops involved rather than solely numbers of cultivars or species.

Buğdaygil ve Baklagil -Buğdaygil Karışımı Meraların Süt İneklerinin Verim Performansı ve Sütün Bileşimine Etkileri

Bu araştırma, Domuz ayrığı (Dactylis glomerata, Pizza, DA), İngiliz çimi (Lolium perenne, Bastion, İÇ) ve Ak üçgül (Trifolium repens, Huia, AÜ) karışımları ile tesis edilen 3 farklı meranın (İÇ, İÇAÜ ve DAAÜ) kuru ot verimi, kimyasal kompozisyonu, süt ineklerinde süt verimi ve sütün kompozisyonuna etkilerinin belirlenmesi amacıyla yürütülmüştür. İki yıl yürütülen bu araştırmada otlatma denemesi, dönüşümlü deneme düzenine göre yapılmıştır. Bu amaçla, her biri 30 günden (8 gün alıştırma ve 22 gün esas dönem) oluşan iki dönemde toplam 6 baş Siyah-Alaca inek (2. laktasyonda ve ortalama 520±26 kg canlı ağırlığında) kullanılmıştır. Hayvanların süt verimi her dönemin birbirini takip eden son beş gününde, sütün besin madde kompozisyonu (kuru madde, yağ ve protein içeriği) ise son üç günü alınan örneklerde tespit edilmiştir. İÇAÜ merasından elde edilen otların asit çözücüde çözünmeyen lif (ADF) içeriği, diğer iki meradan elde edilenlerinkinden daha düşük bulunurken, Net Enerji Laktasyon (NEL) içeriği, birinci yıl, birinci otlatma döneminde, daha yüksek bulunmuştur. Bununla birlikte, incelenen meraların süt verimine etkisi önemsiz, ancak birinci yılda süt protein verimine, ikinci yılda ise süt yağı ve süt kuru maddesine etkilerinin önemli olduğu bulunmuştur. Otlatma döneminin birinci yılında, süt verimi, süt yağı verimi ve protein verimine etkisi ise önemli bulunmuştur. Bu çalışmanın sonuçları, bu çalışma şartları altınında meranın botanik kompozisyonunun sütün miktar ve bileşimi üzerine etkisinin olmadığı ancak, vejetasyon döneminin ilerlemesiyle süt veriminin düştüğü görülmüştür.

Dry matter yield of dryland and irrigated mixtures of Caucasian clover, white clover and perennial ryegrass over 5 years at Lincoln University

This experiment investigated the effects of Caucasian clover (CC), white clover (WC), perennial ryegrass (RG) and their mixtures on dry matter (DM) yield under dryland and irrigated conditions over 5 years (1st July-30th June) at Lincoln University. Seven mixtures of the three species (three pure, three binary and one ternary) were sown in November 1999, grown with and without irrigation, and grazed by sheep. Total annual DM yield in Years 2-6 (2000/2001-2004/2005) was analysed. Clover-RG mixtures yielded more than the average monoculture yields of their constituent species (over-yielding). This diversity effect was 1.8-7.0 t DM/ha for WC-RG over all 5 years and 2.7-4.6 t DM/ ha for CC-RG in Years 3-6. There was no additional yield benefit from the three-species mixture. Diversity effects were due to synergistic interactions between the clovers and RG, which were similar for CC and WC once established. The interspecific interactions persisted despite changes in botanical composition across irrigation levels and years.

Bacillus velezensis as antagonist towards Penicillium roqueforti s.l. in silage: invitro and invivo evaluation.

The present study was conducted to evaluate the antagonistic effect of BacillusvelezensisNRRL B-23189 towards Penicillium roqueforti s.s. and Penicillium paneum (designated together as P.roqueforti s.l.) in silage conditions. Corn silage conditions were simulated invitro, and the impact of B.velezensis culture supernatant or cell suspension on P.roqueforti s.l. growth and roquefortine C production was evaluated. The antagonism was promising, but growth of B.velezensis in corn silage infusion was poor. Additionally, an invivo experiment was carried out with mini-silos containing a mixture of perennial ryegrass and white clover inoculated with P.roquefortis.l. The applied B.velezensis cell suspension was unsuccessful in reducing P.roquefortis.l. numbers, but did not compromise the silage acidification. Although the antagonism observed invitro was promising, the applied B.velezensis cell suspension could not live up to the expectations invivo. To our knowledge, the present study is the first one evaluating the antagonistic properties of B.velezensis towards toxigenic moulds in silage conditions, offering a good base for further research.

Nitrogen balances in organic and conventional arable crop rotations and their relations to nitrogen yield and nitrate leaching losses

Nitrogen (N) flows in organic cropping systems differ considerably from those in conventional systems. The difference is particularly due to the N in organic materials in organic systems as opposed to the mineral N in fertilizer in conventional systems, which differently affect crop N supply and N losses. This implies different responses of conventional and organic cropping systems to N inputs and N management. Therefore, N flow dynamics were studied in a range of arable cropping systems with 4-year crop rotations at three different sites in Denmark varying in soil (coarse sand, loamy sand and sandy loam) and climatic conditions. The long-term field experiments included an incomplete factorial combination of (1) rotations with grass-clover in organic farming (OGC) or grain legumes in organic farming (OGL) or conventionally managed (CGL) systems, (2) with (+CC) and without (−CC) cover crops, and (3) with (+M) and without (−M) animal manure (in OGC and OGL), and with (+F) mineral fertilizer (in CGL). Cover crops in OGC and OGL included a mixture of perennial ryegrass and clover (at the sites with coarse sand and sandy loam soils) or winter rye, fodder radish and vetch (at the site with loamy sand soil), and cover crops in CGL included only perennial ryegrass at all the sites. Higher N input and N output was observed in CGL compared to OGC and OGL. The differences in annual N output in cash crops between CGL and OGL, and CGL and OGC after accounting for effects of differences in N inputs were 15 and 27 kg N ha−1, respectively. The N output was related to N input, with a higher response to mineral N in both fertilizer and manure than to biological N fixation (BNF). The N surplus (difference between N input and N output) was significantly lower in OGL/−M+CC compared with other treatments. The recycled N in above-ground plant residues was highest in OGC/−M+CC where grass-clover cuttings were left in the field, followed by +CC treatments in OGL and CGL. The response of nitrate-N leaching to N input depended on soil type and precipitation, and leaching was reduced by the use of cover crops. The nitrate-N leaching increased with increasing N input at rates of 0.13–0.22 kg N kg−1 N input, and it increased with increasing N surplus at rates of 0.21–0.27 kg N kg−1 N surplus.