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Purpose: The study examines the efficacy of using recycled abattoir waste fertilizer as a sustainable nutrient input for crop Production. Method: Two pot experiments were set up in a controlled environment room to examine biomass yields of ryegrass (Lolium perenne AberMagic), grain yields of spring wheat (Triticum aestivum KWS Cochise), and their micro and macronutrient uptakes, respectively, in an abattoir waste organomineral fertilizer amended soil compared to those treated with inorganic NPK fertilizer. Phosphorus was added at rates of 0, 25, 50, 100, 200, 300, 400, 500, 600, 800, 1000, and 1200 mg P kg-1 in a low P south-west England soil. Results: Total biomass yields of ryegrass in the NPK treatments were higher at application rates greater than 800 mg P kg-1 soil compared with their corresponding abattoir waste organomineral fertilizer (Thallo™) treatments. Total wheat dry grain weights increased with P addition rates in both the Thallo™ and NPK amended soils until the application rates exceeded 800 mg P kg-1 when the dry grain weights started to decline. Micronutrient concentrations in grass produced from Thallo™ fertilizer-amended soils were similar to those from their corresponding NPK fertilizer treatments. Conclusion: This study demonstrated that if the Thallo™ is added at rates not exceeding 200 mg P kg-1 soil to 300 mg P kg-1 soil, it can serve as a sustainable and cost-effective alternative P source for ryegrass and wheat grain production. However, its application did not increase the micronutrient density of ryegrass or wheat grain any more than inorganic NPK additions. [ABSTRACT FROM AUTHOR]

Grasslands vary with diverse forms and functions ranging from monocultures of perennial rye grass to more biodiverse unimproved grasslands which cover around 5% of Europe. Despite the broad diversity of grassland types, within environmental and flood risk models grasslands are frequently represented by a singular set of hydrological and structural parameters which belies their diversity and complexity. This study aimed to determine empirically the extent to which improved versus unimproved grasslands exhibit different hydrological connectivity. Working in SW England at neighbouring field sites with comparable slopes and rainfall regimes, we used unpiloted aerial vehicles to survey a tussocky Molinia caerulea dominated unimproved grassland field (MCUG) field and a Lolium perenne dominated improved grassland (LPIG) field. Using digital photogrammetry workflows applied to the overlapping aerial images, we produced a digital surface model (DSM) at 0.03‐m resolution from which flow pathways were modelled using GIS and compared with 1‐m LiDAR and DSM produced by a global navigation satellite system (GNSS). MCUG had longer, tortuous pathways through the dense tussock network with a drainage density of 2.54 m m−2. This was significantly greater than drainage density in the LPIG (1.82 m m−2). As a result of this study, we rescaled the Manning's n value for MCUG according to photogrammetrically‐derived roughness values. We suggest it should lie between 0.075 and 0.09. Our data shows that MCUG can play an important role in reducing overland flow impacts when compared to LPIG through lower connectivity which can delay run‐off to rivers. [ABSTRACT FROM AUTHOR]

The effect of spreading mown perennial ryegrass (Lolium perenne) herbage over the total ground area on water loss during field-wilting was compared with leaving herbage in swaths (three swaths put together into one, occupying 0·18 of ground area) in three experiments. Spread crops were not tedded during wilting but were rowed up immediately before harvest. In all experiments, conventional silage-making equipment was used on a field scale. Feeding value was assessed with lactating dairy cows and growing heifers (Experiment 1) and sheep (Experiment 3). The periods of field wilting were 48 h (Experiment 1), 24 h (Experiment 2) and both 24 h and 48 h (Experiment 3). Spreading the crop was associated with larger increases in loss of water in all three experiments compared with leaving grass in swaths. Losses of dry matter (DM) during wilting were similar in Experiment 2 but were higher for the swathed crop wilted for 48 h than for 24 h in Experiment 3. Spreading resulted in restricted fermentations associated with higher crop DM contents at ensiling. In Experiment 1 the concentrations of DM, ash and water-soluble carbohydrate in silage were higher (P < 0·001) for spreading the crop and the concentrations of crude protein and neutral-detergent fibre were lower (P < 0·05) than for swathed material. In Experiment 3, spreading was associated with higher concentrations of water-soluble carbohydrates and ethanol and lower concentrations of fermentation acids, ammonia-N and neutralizing value in silage. Voluntary DM intake of silage by dairy cows and heifers was higher for spread than for swathed material (P < 0·05), but in Experiment 3 (sheep) there were no significant differences between treatments in voluntary intake of DM. The increased intake by dairy cows of silage from spread herbage was reflected in increased concentrations of milk fat (P < 0·01) and protein (P < 0·05) but not in milk yield (P > 0·05). It is concluded that spreading herbage during field wilting prior to ensiling accelerates water loss and has the potential to improve the feeding value of the ensiled product. [ABSTRACT FROM AUTHOR]

Dazomet, applied to the soil in September 1972, increased the dry matter yield in 1973 of perennial ryegrass (Lolium perenne L.) cv. Gremie sown that spring in Hertfordshire. The greatest increase (60 per cent) was where least nitrogen had been applied and was not apparently the result of differences in pathogen or pest incidence. Sprays of the fungicides benodanil and benomyl, and drenches of captafol, did not affect yield in 1973 or 1974, although benodanil controlled crown rust (Puccinia coronata Corda) in August and September 1973. Sprays of the acaricide endosulfan and the aphicide menazon had no detectable effects in 1973. In 1974, endosulfan sprays, either alone or " with menazon, controlled Abacarus hystrix (Nal.), the mite vector of ryegrass mosaic virus (RMV), decreased RMV incidence from 54 to 26 per cent and increased dry matter yield by six per cent. Mildew (Erysiphe graminis DC.) was observed in 1973 and leaf spot (Drechslera spp.) was common in 1973 and 1974, but infection by both diseases was only slight. The incidence of barley yellow dwarf virus was slight and not apparently affected by the treatments. Root discoloration was common but not affected by dazomet or captafol. Fusarium culmorum (W. G. Smith) Sacc. was commonly isolated from very discoloured roots and one isolate, which was weakly pathogenic to ryegrass, killed wheat seedlings. After cutting, patches of grass in plots given 150 kg nitrogen/ha/cut showed poor regrowth, but this could not be associated with pathogens. Mildew and RMV were most common on plots given most nitrogen (150 kg N/ha/cut). RMV and its vectors were apparently more detrimental during the experiment than were other pathogens. [ABSTRACT FROM AUTHOR]

This article cites a study that described lolium (L.) mottle virus (LMV). A previously unrecorded virus with isometric particles 27 nanometer diameter had been isolated from L. perenne and Cynosurus (C.) cristatus from Eire and from C. cristatus from Yorkshire, England. Then this was named LMV. The virus could be inoculated into cultivars of wheat, oats, barley and rye, and Lagurus ovatus. It was symptomless in L. multiflorum and Phleum pratense. Some properties of LMV were reported. The virus, though readily sap transmissible, was not transmitted by two Oulema species or by three species of aphids.

A field-scale experiment was conducted to compare the suitability of two organomineral fertiliser (OMF) formulations (OMF10- 10 : 4 : 4 and OMF15-15 : 4 : 4) with urea and biosolids granules applied to perennial ryegrass. Results showed a 25% to 30%increase in dry matter yield (DMY) with application of OMF compared with biosolids granules but about 5% lower than urea. For OMF, an average input of 0.8 × Nmax yielded 0.98 ×DMYmax which was similar to that of urea; whereas, for biosolids, a yield of 0.92 ×DMYmax required an input of 0.6 × Nmax but DMY was lower (P < 0.05). Agronomic efficiencies with OMF were in the range of 26 to 35 kg kg-1, approximately double those of biosolids but about 5% to 10% lower than urea. Soil extractable P levels remained close to constant; therefore, soil P Index was not affected by OMF application. This result supported the reasons for the proposed OMF formulations and demonstrated the advantage of the products compared with biosolids which induced an increase (P> 0.05), in soil extractable P. The application of OMF at rates which do not exceed the optimum N rate for the grass crop should not induce significant changes in soil P Index including application to soils with satisfactory P levels. OMF application strategies are discussed which will enable minimising environmental concerns and maximising fertiliser use efficiency. [ABSTRACT FROM AUTHOR]

The Olsen method is an indicator of plant-available phosphorus (P). The effect of time and temperature on residual phosphate in soils was measured using the Olsen method in a pot experiment. Four soils were investigated: two from Pakistan and one each from England (calcareous) and Colombia (acidic). Two levels of residual phosphate were developed in each soil after addition of phosphate by incubation at either 10 °C or 45 °C. The amount of phosphate added was based on the P maximum of each soil, calculated using the Langmuir equation. Ryegrass was used as the test crop. The pooled data for the four soils incubated at 10 °C showed good correlation between Olsen P and dry matter yield or P uptake (r2 = 0.85 and 0.77, respectively), whereas at 45 °C, each soil had its own relationship and pooled data did not show correlation of Olsen P with dry matter yield or P uptake. When the data at both temperatures were pooled, Olsen P was a good indicator of yield and uptake for the English soil. For the Pakistani soils, Olsen P after 45 °C treatment was an underestimate relative to the 10 °C data and for the Colombian soil it was an overestimate. The reasons for these differences need to be explored further before high temperature incubation can be used to simulate long-term changes in the field. [ABSTRACT FROM AUTHOR]

This study examines the effectiveness of a model called LINGRA-N-Plus to simulate the interaction of climate, soil and management on the green leaf and total dry matter yields of ryegrass in England and Wales. The LINGRA-N-Plus model includes modifications of the LINGRA-N model such as temperature- and moisture-dependent soil nitrogen mineralization and differential partitioning to leaves and stems with thermal time from the last harvest. The resulting model was calibrated against the green leaf and total grass yields from a harvest interval x nitrogen application experiment described by Wilman et al. (1976). When the LINGRA-N-Plus model was validated against total grass yields from nitrogen experiments at ten sites described by Morrison et al. (1980), its modelling efficiency improved greatly compared to the original LINGRA-N. High predicted yields, at zero nitrogen application, were related to soils with a high initial nitrogen content. The lowest predicted yields occurred at sites with low rainfall and shallow rooting depth; mitigating the effect of drought at such sites increased yields by up to 4 t ha−1. The results highlight the usefulness of grass models, such as LINGRA-N-Plus, to explore the combined effects of climate, soil, and management, like nitrogen application, and harvest intervals on grass productivity. [ABSTRACT FROM AUTHOR]

In a field experiment carried out over 3 years, the nitrate content of herbage from perennial ryegrass (Lolium perenne) swards increased exponentially with nitrogen application rate, but herbage nitrate content appeared to reach potentially dangerous concentrations only when nitrogen application rates were greater than those needed to stimulate dry-matter production. Thus, on average over all the harvests, maximum yield could be obtained with annual application rates of 400 kg N ha–1 (six applications of 67 kg N ha–1) for perennial ryegrass and 300 kg N ha–1 (six applications of 50 kg N ha–1) for perennial ryegrass/white clover (Trifolium repens) swards, whereas the mean nitrate concentrations were 3340 and 2929 mg NO3 kg–1 dry matter (DM) respectively. Nitrate content, however, varied considerably from harvest to harvest, reaching maxima of 9345 mg NO3 kg–1 DM at 400 kg N ha–1 for perennial ryegrass and 6255 mg NO3 kg–1 DM at 300 kg N ha–1 for perennial ryegrass/white clover. The nitrate content of herbage from perennial ryegrass/white clover swards was always greater than that of perennial ryegrass swards receiving the same rate of nitrogen application, even though in the herbage from the mixed sward the nitrate content of white clover was usually less than half that of the perennial ryegrass component. The physical environment did not have a clearly interpretable effect on nitrate content, although herbage harvested in May had a much lower nitrate content than that harvested at any other time of the season. It was not possible to find a single multiple regression equation relating herbage nitrate content to nitrogen application and to other environmental variables that explained more than 60% of the variance in herbage nitrate, but it is suggested that, by reducing the later-season nitrogen applications from 67 to 50 and finally to 33 kg N ha–1 for perennial ryegrass and from 50 to 33 kg N ha–1 for perennial ryegrass/white clover, it would be possible to achieve over 90% of the maximum yield while reducing average nitrate content to <40% of that at maximum yield, with no samples containing more than 2300 mg NO3 kg –1 DM. [ABSTRACT FROM AUTHOR]

In experiments in 1979 and 1980 in eastern England, the spread of eriophyid mites and ryegrass mosaic virus (RMV) from transplanted old sward through plots of newly sewn Italian ryegrass greatly exceeded spread by windborne mites from outside the plots. During the summer and autumn of each year, mites and RMV spread at least one metre through the ryegrass (6/7 rows) from the old sward. Applying aldicarb (10 kg/ha equivalent) to the seedbed before sowing the Italian ryegrass prevented colonisation by mites and greatly decreased spread of RMV from old sward. lt is concluded that old diseased swards should be completely killed before reseeding and that RMV is likely to spread quickly to plants slot-seeded into old pastures. The use of acaricides might prevent this spread but would be costly. [ABSTRACT FROM AUTHOR]

Forage plants underpin the livestock industry. Selective breeding, including polyploidization, where genome size is increased by whole genome duplication, changes the productivity and stress tolerance of new varieties. We conducted a growth chamber experiment to investigate the likely responses of Lolium perenne L. to drought, testing four diploid and four tetraploid varieties. We simulated projected spring and summer temperatures for the South-West of England in 2080, applying three projected rainfall scenarios, which varied in drought severity. Drought caused a reduction in productivity, but there was substantial variation between varieties (up to 82%), with the optimal variety changing depending on drought severity. Across three harvests, productivity declined by 43% and 27% (dry biomass) for the severe and likely drought scenarios, respectively. In the final harvest, tetraploids exhibited a greater biomass under severe drought, whereas diploids had a greater biomass under the current rainfall and likely drought scenarios. Longer stomata were observed in tetraploids; however, stomatal conductance was not significantly different between ploidy levels. Trait selection will be important for future drought adaptation. Local climate projections will need to be consulted when selecting L. perenne varieties to tolerate the spatially variable reductions in future rainfall. [ABSTRACT FROM AUTHOR]

This article describes new or uncommon plant diseases and pests in a farm near Harleston, Norfolk in England. It is noted that plant of perennial ryegrass show flecking, particularly on the older leaves, and die-back from the leaf tips. Individual lesions were elliptical, purplish brown, 1-4 millimeters long and less than 1 mm wide. Large lesions had paler centers and carried clusters of white conidia characteristic of Mastigoporium album Riess. The conidia were elliptical, septate, with filiform appendages from apical or subapical cells at the distal end.

This article discusses the occurrence of Rhynchosporium secalis on Westerwolths Ryegrass. A severe infection by Rhynchosporium secalis was observed on Lolium multiflorum var. Westerwoldicum at Compton Chamberlayne in Wiltshire, England on April 1, 1960. Die-back of the leaf blades was first seen by the farmer in early February 1960 and it continued until the crop was grazed in early April 1960. Characteristic Rhynchosporium lesions were found at the tips of the leaves and towards the middle of the laminae. Die-back followed the enlargement and coalescence of these lesions. Microscopic examination revealed one-septate conidia with beaked upper cells, typical of Rhynchosporium secalis.

Adoption of rotational grazing or multi-species herbal leys, planting trees and integrating livestock into arable rotations can increase agricultural productivity and carbon storage on temperate ruminant livestock farms. However, farmers frequently have rational reasons for not adopting seemingly beneficial management practices. Here, we conduct semi-structured interviews with sheep and beef cattle farmers and industry representatives in England, to determine the advantages, disadvantages, and reasons for non-adoption of these four management practices. We find key reasons that farmers rationally do not adopt these practices include capital outlay, incompatibility with farming objectives, and the risk that desired benefits are not delivered. [ABSTRACT FROM AUTHOR]

This article presents a study on the effect of ley grasses on the carry-over of Take-all fungus in the South-West England. An analysis of several hundred cases of Take-all reported from 1946 to 1951 showed that only about 8% occurred in crops after a one-year ley break, and only about 4% after a long ley or old pasture. We had also followed the cropping on several farms, taking samples of soil from under the various crops and growing test wheat seedlings in them. These tests showed a uniform decline of the infectivity to safe levels after two years under leys, irrespective of the seeds mixtures used. A field experiment was conducted on heavily infected land over the period 1950 to 1954 to test the effects on carry-over of the four commonly-used grasses, such as timothy, meadow fescue, perennial ryegrass and cocksfoot.

The article focuses on damage to grassland by larvae of the common leaf weevil, Phyllobiua pyri. In September 1972, a paddock of five acres at Cambridgeshire, England was found to be suffering an overall sward death of about 25 percent. Examination of the turf and top soil revealed a large infestation of mature larvae of a leaf weevil. Examination of the turf and top soil revealed fully grown weevil larvae among the grass roots at depths of 1-8 centimeters. There were no larvae in the middle of the dead patches but elsewhere weevil numbers ranged from 12-20 larvae per 30 square centimeter. The hedgerow bordering the stream consisted of oak trees and a hawthorn hedge, on which the adult weevils presumably fed.