Timothy Yield Research Articles

Effects of Microbial Inoculants Combined with Chemical Fertilizer on Growth and Soil Nutrient Dynamics of Timothy (Phleum pratense L.)

Microbial inoculants derived from plant growth-promoting rhizobacteria (PGPR) offer eco-friendly alternatives to traditional chemical fertilizers, maintaining microbiota balance in agricultural systems. However, limited research has explored the combined effects of microbial inoculants and chemical fertilizers on crop growth and soil properties. In this study, we investigated seven fertilizer combinations, ranging from no fertilizer to various proportions of chemical fertilizers with microbial inoculants, on timothy (Phleum pratense L.) growth, chlorophyll content, soil properties, enzyme activities, and soil microbial communities. A randomized block design was employed to analyze these effects. The results indicate that the combination of 85% chemical fertilizer with microbial inoculants significantly increased timothy yield and chlorophyll content. In addition, a reduction to 55% chemical fertilizer in conjunction with microbial inoculants resulted in comparable yield to that of 100% fertilizer with no inoculants. The microbial inoculants treatments notably elevated soil catalase, urease, acid phosphatase, and invertase activities, along with soil fast-acting nutrient content. The sequencing results show that the abundance of beneficial bacteria increased, while that of fungi decreased in the soil rhizosphere after the application of microbial inoculants. This study underscored the potential of microbial inoculants combined with reductions in chemical fertilizers to enhance soil microbiology, nutrient content, and beneficial microbial abundance while suppressing pathogenic fungi, thereby promoting timothy growth and yield. These findings provide a theoretical basis for the use of microbial inoculants in sustainable agricultural practices, providing valuable insights for optimizing microbial inoculants and chemical fertilizer formulations to mitigate the sustainability challenges posed by conventional fertilizers.

Impacts of organic soil amendments on forage grass production under different soil conditions

Organic amendments can improve grassland productivity. Timothy and tall fescue were sown on a sandy loam and a coarse sand at Særheim, Norway, in September 2016 and on a loamy sand at Skierniewice, Poland, in April 2017, and cut and fertilised according to normal practices for the two regions from 2017 to 2019. At both sites, 0.75 kg DM m-2 of either digested or undigested manure (the latter with or without 2.9 kg biochar m-2) were incorporated prior to sowing. On the coarse sand at Særheim, total seasonal tall fescue yield in 2018 was 46–60% higher in the organic amendment treatments, and total seasonal timothy yield in the digestate treatment was 97% higher, than in the control treatment for the same species with only mineral fertiliser. On the sandy loam at Særheim and the loamy sand at Skierniewice, none of the amendments resulted in significant yield increments. These results indicate a clear effect on soil type on grassland biomass response to organic amendments.

Increase in perennial forage yields driven by climate change, at Apukka Research Station, Rovaniemi, 1980-2017

The official variety trials at Rovaniemi, Finland (66.58°N, 26.01°E) in 1980–2017 show a substantial increase in dry matter yields (DMY) of timothy (Phleum pratense), meadow fescue (Festuca pratensis) and tall fescue (Festuca arundinacea), coinciding with a 156 °Cd increase in the average growing season Tsum and a 461 °Cd decrease in the average winter frost sum for the same period. The annual DMY of timothy was 3128, 4668, 8385 and 9352 kg ha-1 in the periods (P) 1980–1989 (P1), 1990–1999 (P2), 2000–2009 (P3), and 2010–2017 (P4). The first cut yielded 1792, 2166, 4008 and 4473, and the second cut 1337, 2503, 4378 and 4879 kg ha-1, respectively. Yields of meadow fescue followed a similar pattern. The first cut was about ten days and the second cut about one week earlier on P4 than on P1. Shorter snow cover period, milder winters, higher live ground cover of timothy in spring, and higher temperature sum during the growing season were most likely responsible for the yield increase. The results indicate a strong impact of climate change on DMY of perennial forage crops in the north.

Advantages of grass-legume mixture for improvement of crop growth and reducing potential nitrogen loss in a boreal climate

A three-year field experiment was established to assess intercropping for sustainable forage production in Finland. In split-plot design, fertilizer treatment with unfertilized control, organic fertilizer, and synthetic fertilizer was the main plot factor, and crop treatment with fallow, red clover (Trifolium pratense), timothy (Phleum pratense), and a mixture of red clover and timothy was the sub-plot factor. Dry matter, carbon and nitrogen yields in mixture plots were highest with relatively high N% and the optimum C:N ratio (p < 0.05). Fertilization increased annual yields of mixture and timothy but not that of red clover. Soil NO3-N changed over time (p < 0.05) and was highest in fallow, followed by red clover, mixture, and timothy (p < 0.05), and the decrease during late growing season was smaller in the mixture and timothy plots. At the end of the experiment, soil C/NO3-N ratio was higher in timothy and mixture while lower in red clover and fallow plots (p < 0.05), and the relationship between soil DNA and NO3-N content may indicate that the potential nitrogen loss was lower in mixture and timothy than that in fallow and red clover plots.

Simulation of timothy nutritive value: A comparison of three process-based models

Different forage grass models are used to simulate forage yield and nutritive attributes, but these models are seldom compared, particularly those for timothy (Phleum pratense L.), a widely grown forage grass species in agricultural regions with a cold temperate climate. We compared the models BASGRA, CATIMO and STICS for their predictions of timothy crude protein (CP) concentration, neutral detergent fibre (NDF) concentration and NDF digestibility (dNDF), three important forage nutritive attributes. Data on CP and NDF concentrations, and dNDF and the associated weather and soil data for seven cultivars, taken from eight field experiments in Canada, Finland, Norway, and Sweden, were divided into calibration and validation datasets. Model parameters were estimated for each cultivar separately (cultivar-specific calibration) and for all cultivars together (generic calibration), using different methods for the three models. Normalized root mean square error (RMSE) in prediction of CP concentration varied between 16 and 26% for BASGRA, 45 and 101% for CATIMO and 23 and 40% for STICS across the two calibration methods and the calibration and validation datasets. Normalised RMSE in prediction of NDF concentration varied between 8 and 13% for BASGRA, 14 and 21% for CATIMO and 8 and 12% for STICS, while for dNDF it varied between 7 and 22% for BASGRA, 7 and 38% for CATIMO and 5 and 6% for STICS. Cultivar-specific calibration improved the performance of CATIMO and STICS, but not BASGRA, compared with generic calibration. The prediction accuracy for NDF concentration and dNDF with the three models was within the same range or better than that for forage dry matter (DM) yield of timothy. Overall, the three models performed well in predicting some nutritive attributes and yield in Northern Europe and Canada, but improvements are required, particularly to increase the prediction accuracy of CP concentration.

Carbon capture efficiency, yield, nutrient uptake and trafficability of different grass species on a cultivated peat soil

Loss of organic matter from cultivated peat soils is a threat to farmers, due to the surface subsidence associated with organic matter loss, and to the atmosphere, due to CO2 and N2O emissions from the soil. In a three-year field experiment (2015–2017) on a drained, cultivated fen peat in southern Sweden, we tested whether reed canary grass (Phalaris arundinacea L.) and tall fescue (Festuca arundinacea Schreb.) perform better on peat soils than the commonly grown timothy grass (Phleum pratense L.), without increasing greenhouse gas emissions. In the experiment, we compared yield, nutrient uptake, penetration resistance and loss of organic matter measured as greenhouse gas emissions (CO2, N2O and CH4). Yield of timothy was significantly lower than that of reed canary grass and tall fescue in 2016, and lower than that of reed canary grass in 2017. Yield level increased over time, with total dry matter yield in 2017 of 11.7 Mg ha−1 yr−1 for timothy, 13.5 Mg ha−1 yr−1 for tall fescue and 14.3 Mg ha−1 yr−1 for reed canary grass. Total removal of all macronutrients in 2016 was higher in reed canary grass and tall fescue than in timothy. For nitrogen (N), reed canary grass removed a total of 173 kg N ha−1 yr−1, tall fescue 169 kg ha−1 yr−1 and timothy 121 kg ha−1 yr−1, while the fertilisation rate was only 50 kg N ha−1. There were no differences in trafficability, measured as penetration resistance. Measurements of greenhouse gas emissions in the snow-free season in 2016 and 2017 using manual dark chambers (CO2, N2O and CH4) and in 2016 automatic dark chambers (CO2) revealed only small differences in CO2 emissions between the treatments. The N2O emissions were also low and CH4 emissions were very low and in general negative. The estimated carbon capture efficiency (ratio of C in aboveground biomass plus roots to emitted CO2-C measured by the automatic chambers) for the growing season (May–October) in 2016 was lowest for timothy (0.61) and higher for reed canary grass and tall fescue (0.70 and 0.70, respectively). Reed canary grass and tall fescue are thus promising alternatives to timothy on peat soils regarding yield, nutrient removal and carbon capture efficiency.

Influence of foliar fertilization with amino acid preparations on morphological traits and seed yield of timothy

The aim of the study was to determine the influence of amino acid fertilizer on yielding ability, morphological characteristics and chlorophyll index of timothy cv. Owacja grown for seed. The experiment was conducted in 2015–2017 at the Experimental Station in Prusy near Krakow, which belongs to the Institute of Plant Production of the University of Agriculture in Krakow. The field trial was set up as a randomized block design with four replications. The soil in the experimental field was a degraded chernozem formed from loess. The plots were sprayed with three doses of Microfert amino acid fertilizer: 1.8, 3.0 and 4.5 L/ha. The highest application rate of foliar fertilization with amino acids (4.5 L/ha) caused a significant (P ≤ 0.05) increase in seed yield and germination capacity compared with the control plot. Successive years of use also had a significant effect on timothy seed yield, which was the highest during the first year of the study. Morphological characteristics were found to improve (taller and longer inflorescences and leaf blades). Satisfactory results (seed yield higher by about 11% to the control plot) were also obtained on the plots where the fertilizer was applied at the rate of 3.0 L/ha.

Predicted Yield and Nutritive Value of an Alfalfa–Timothy Mixture under Climate Change and Elevated Atmospheric Carbon Dioxide

Climate change studies have often focused on individual forage species although legume‐grass mixtures are predominant on dairy farms in northern areas of North America. We assessed the effect of (i) future climate conditions (temperature and precipitation) and elevated atmospheric CO2 concentration ([CO2]), separately and together, on yield of alfalfa (Medicago sativa L.) and timothy (Phleum pratense L.), grown alone or in mixture, and (ii) an adaptation strategy (timing and number of harvests) on future yield and nutritive value of an alfalfa–timothy mixture. Forage dry matter (DM) yield and nutritive value for two contrasting climate areas in eastern Canada were simulated with the Integrated Farm System Model over two future periods (2020–2049 and 2050–2079) using three climate models and two representative concentration pathways (RCP 4.5 and 8.5) of greenhouse gas emissions. Under projected future climate and without adaptation, annual forage yield of both species and the mixture increased in the colder area and decreased in the warmer area. In both areas, first‐cut yield increased due to faster growing degree‐day accumulation, while regrowth yield decreased due to greater water and temperature stresses. Under elevated [CO2], annual yield and the alfalfa percentage in the mixture increased. When combining climate change and elevated [CO2], yield increased, except with the more drastic scenario (RCP 8.5, 2050–2079) in the warmer area, and forage nutritive value was reduced. With adaptation, the mixture yield was increased from 5 to 35%, while nutritive value was generally maintained under all future scenarios, mostly because of additional cuts.Core Ideas In eastern Canada, colder areas will benefit the most from climate change. In future climate, water and temperature stresses will reduce forage summer regrowth. Elevated CO2 will result in a higher yield increase in alfalfa than in timothy. When adapting harvest timing and number, annual forage mixture yield will increase. When adapting harvest timing and number, forage nutritive value will be maintained.

Impact of soil type extrapolation on timothy grass yield under baseline and future climate conditions in southeastern Norway

CR Climate Research Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials CR 65:71-86 (2015) - DOI: https://doi.org/10.3354/cr01303 Contribution to the CR Special: 'Modelling climate change impacts for food security' Impact of soil type extrapolation on timothy grass yield under baseline and future climate conditions in southeastern Norway Tomas Persson1,*, Sigrun Kværnø2, Mats Höglind1 1Agriculture Division, Norwegian Institute for Agricultural and Environmental Research, 4353 Klepp Stasjon, Norway 2Environment Division, Norwegian Institute for Agricultural and Environmental Research, Fredrik A. Dahls vei 20, 1430 Ås, Norway *Corresponding author: tomas.persson@bioforsk.no ABSTRACT: Interactions between soil properties and climate affect forage grass productivity. Dynamic models, simulating crop performance as a function of environmental conditions, are valid for a specific location with given soil and weather conditions. Extrapolations of local soil properties to larger regions can help assess the requirement for soil input in regional yield estimations. Using the LINGRA model, we simulated the regional yield level and variability of timothy, a forage grass, in Akershus and Østfold counties, Norway. Soils were grouped according to physical similarities according to 4 sets of criteria. This resulted in 66, 15, 5 and 1 groups of soils. The properties of the soil with the largest area was extrapolated to the other soils within each group and input to the simulations. All analyses were conducted for 100 yr of generated weather representing the period 1961-1990, and climate projections for the period 2046-2065, the Intergovernmental Panel on Climate Change greenhouse gas emission scenario A1B, and 4 global climate models. The simulated regional seasonal timothy yields were 5-13% lower on average and had higher inter-annual variability for the least detailed soil extrapolation than for the other soil extrapolations, across climates. There were up to 20% spatial intra-regional differences in simulated yield between soil extrapolations. The results indicate that, for conditions similar to these studied here, a few representative profiles are sufficient for simulations of average regional seasonal timothy yield. More spatially detailed yield analyses would benefit from more detailed soil input. KEY WORDS: Climate change scenarios · Crop modelling · Forage grass · LINGRA · Soil properties · Spatial variability · Phleum pretense · Poaceae Full text in pdf format PreviousNextCite this article as: Persson T, Kværnø S, Höglind M (2015) Impact of soil type extrapolation on timothy grass yield under baseline and future climate conditions in southeastern Norway. Clim Res 65:71-86. https://doi.org/10.3354/cr01303 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in CR Vol. 65. Online publication date: September 28, 2015 Print ISSN: 0936-577X; Online ISSN: 1616-1572 Copyright © 2015 Inter-Research.

Simulating forage crop production in a northern climate with the Integrated Farm System Model

Jégo, G., Rotz, C. A., Bélanger, G., Tremblay, G. F., Charbonneau, E. and Pellerin, D. 2015. Simulating forage crop production in a northern climate with the Integrated Farm System Model. Can. J. Plant Sci. 95: 745–757. Whole-farm simulation models are useful tools for evaluating the effect of management practices and climate variability on the agro-environmental and economic performance of farms. A few process-based farm-scale models have been developed, but none has been evaluated in northern regions with boreal and hemiboreal climates characterized by a short growing season and a long period with snow cover. The study objectives were to calibrate the grass sub-model of the Integrated Farm System Model (IFSM) and evaluate its predictions of yield and nutritive value of timothy and alfalfa, grown alone or in a mixture, using experimental field data from across Canada, andto assess IFSM's predictions of yield of major annual crops grown on dairy farms in eastern Canada using regional yield data from two contrasting regions. Several timothy and alfalfa datasets combining sites, years, harvests, and N fertilization rates were used to calibrate and evaluate the model. For timothy and alfalfa, the model's accuracy was globally satisfactory in predicting dry matter yield and neutral detergent fiber concentration with a normalized root mean square error (NRMSE)<30%. For N uptake, the scatter was a bit larger, especially for timothy (NRMSE= 49%), mainly because of a small range in the measured data. The model's accuracy for predicting the yield of annual crops was generally good, with an NRMSE<30%. Adding timothy and alfalfa to the grass sub-model of IFSM and verifying the model's performance for annual crops confirmed that IFSM can be used in northern regions of North America. In addition, the model was able to simulate the yield and nutritive value of a timothy–alfalfa mixture, which is the most common perennial mixture used in Canada.

Cover crop stubble and straw management in seed production of timothy (Phleum pratense L.), meadow fescue (Festuca pratensis Huds.), and red clover (Trifolium pratense L.)

The market for cereal straw has diminished in many seed-production areas due to less livestock. Seed growers, therefore, want to chop and return the straw. The objective was to investigate the effect of cover crop stubble height and straw management on vegetative growth in autumn and the following year's seed yield of timothy, meadow fescue, and red clover. The plan included two stubble heights (5–10 cm and 20–30 cm) combined with four different straw and stubble managements, (A) straw removal, (B) straw chopping at combining, (C) flail-chopping with tractor after combining, and (D) straw chopping in two operations (B + C). The cover crop was either spring barley or spring wheat. On average for all trials and plots where the straw was removed, by the end of the sowing year, a tendency of 9% more tillers of meadow fescue, 29% more tillers of timothy, and 27% more plants of red clover was produced on plots with short than with long stubble. In the following year, the average seed yields were not significantly affected by stubble height in meadow fescue and timothy, but 11% higher on plots with short than with long stubble in red clover. This indicates that red clover is more vulnerable to the shade created by a long stubble than the two grass species. When the stubble was short, straw chopping produced equally high seed yields as straw removal in all species. For seed growers without their own husbandry or not receiving any payment for the cover crop straw, chopping of straw is, therefore, recommended as an environmentally sound and cost-saving alternative to straw removal. The straw must be chopped with sharp knives as finely as possible and spread evenly on the soil surface to facilitate rapid decomposition and rapid penetration by the undersown seed crop.

Evaluation of the LINGRA timothy model under Nordic conditions

Simulation models are frequently applied to determine the production potential of forage grasses under various scenarios, including climate change. Thorough calibrations and evaluations of forage grass models can help improve their applicability. This study evaluated the ability of the Light Interception and Utilization Simulator-GRAss (LINGRA) model to predict biomass yield of timothy (Phleum pratense L. cv. Grindstad) in the Nordic countries. Variety trial data for the first and second year after establishment were obtained for seven locations: Jokioinen, Finland (60°48′ N; 23°29′ E), Maaninka, Finland (63°09′ N; 27°18′ E), Korpa, Iceland (64°09′ N; 21°45′ W), Særheim, Norway (58°41′ N; 5°39′ E), Lillerud, Sweden (59°24′ N; 13°16′ E), Östersund, Sweden (63°15′ N; 14°34′ E) and Umeå, Sweden (63°49′ N; 20°13′ E) from 1992 to 2012. Two calibrations of the LINGRA model were carried out using Bayesian techniques. In the first of these (Særheim calibration), data on biomass yield and underlying variables obtained from independent field trials at Særheim were used. In the second (Nordic calibration), biomass data from the other locations were used as well. The model was validated against the remaining set of biomass yields from all locations not included in the Nordic calibration. The observed total seasonal yield the first and second year after establishment was 913 and 991gDMm−2 respectively on average across the locations. The corresponding average simulated yield after the Særheim calibration was 1044 (root mean square error (RMSE) 258) and 1112gDMm−2 (RMSE 312), respectively. After the Nordic calibration, the simulated average total seasonal yield was 863 (RMSE 242) the first year and 927gDMm−2 (RMSE 271) the second year after establishment. The differences between the observed and simulated first cut yield followed the same patterns, whereas the prediction accuracy for second cut yield did not differ substantially between the calibration approaches. Using the parameter set from the Nordic region decreased the model predictability at Særheim compared with only using model parameters derived from this location. These results show that using biomass data from several locations, instead of only one specific location, in the calibration of the LINGRA model improved the overall prediction accuracy of first cut dry matter yield and total seasonal dry matter yield across an environmentally heterogeneous region. To further analyse the usefulness of including multi-site data in forage grass model calibrations, other forage grass models could be evaluated against the same dataset.

Timothy yield and nutritive value with a three-harvest system under the projected future climate in Canada

Jing, Q., Bélanger, G., Qian, B. and Baron, V. 2014. Timothy yield and nutritive value with a three-harvest system under the projected future climate in Canada. Can. J. Plant Sci. 94: 213–222. Timothy (Phleum pratense L.) is harvested twice annually in Canada but with projected climate change, an additional harvest may be possible. Our objective was to evaluate the impact on timothy dry matter (DM) yield and key nutritive value attributes of shifting from a two- to a three-harvest system under projected future climate conditions at 10 sites across Canada. Future climate scenarios were generated with a stochastic weather generator (AAFC-WG) using two global climate models under the forcing of two Intergovernmental Panel on Climate Change emission scenarios and, then, used by the CATIMO (Canadian Timothy Model) grass model to simulate DM yield and key nutritive value attributes. Under future climate scenarios (2040–2069), the additional harvest and the resulting three-harvest system are expected to increase annual DM yield (+0.46 to +2.47 Mg DM ha−1) compared with a two-harvest system across Canada but the yield increment will on average be greater in eastern Canada (1.88 Mg DM ha−1) and Agassiz (2.02 Mg DM ha−1) than in the prairie provinces of Canada (0.84 Mg DM ha−1). The DM yield of the first harvest in a three-harvest system is expected to be less than in the two-harvest system, while that of the second harvest would be greater. Decreases in average neutral detergent fibre (NDF) concentration (−19 g kg−1DM) and digestibility (dNDF, −5 g kg−1NDF) are also expected with the three-harvest system under future conditions. Our results indicate that timothy will take advantage of projected climate change, through taking a third harvest, thereby increasing annual DM production.

Timothy yield and nutritive value with a three-harvest system under the projected future climate in Canada

Jing, Q., Belanger, G., Qian, B. and Baron, V. 2014. Timothy yield and nutritive value with a three-harvest system under the projected future climate in Canada. Can. J. Plant Sci. 94: 213-222. Timothy (Phleum pratense L.) is harvested twice annually in Canada but with projected climate change, an additional harvest may be possible. Our objective was to evaluate the impact on timothy dry matter (DM) yield and key nutritive value attributes of shifting from a two- to a three-harvest system under projected future climate conditions at 10 sites across Canada. Future climate scenarios were generated with a stochastic weather generator (AAFC-WG) using two global climate models under the forcing of two Intergovernmental Panel on Climate Change emission scenarios and, then, used by the CATIMO (Canadian Timothy Model) grass model to simulate DM yield and key nutritive value attributes. Under future climate scenarios (2040-2069), the additional harvest and the resulting three-harvest system are expected to increase...

Timothy Yield and Nutritive Value under Climate Change in Canada

Timothy (Phleum pratense L.) is a dominant forage grass in Canada but its performance under projected future climate conditions has not been evaluated. This study combined the grass model CATIMO (Canadian Timothy Model) with baseline (1961–1990) and projected future (2040–2069) climate scenarios to assess the response of timothy to climate change at 10 sites across Canada. Projected future conditions are expected to have the following effects on timothy: (i) earlier growth onset (10‐site average: –21 d; range: –4 to –40 d), date of first harvest (–15 d; –11 to –25 d), and date of second harvest (–20 d; –17 to –29 d), along with a later end to the growing season (+12 d; 0 to +18 d); (ii) increased dry matter (DM) yield at first harvest (+355 kg ha–1; –917 to +826 kg ha–1) but decreased DM yield at second harvest (–427 kg ha–1; +47 to –936 kg ha–1); (iii) increased neutral detergent fiber (NDF) concentration at first harvest (+22 g kg–1 DM; –22 to +94 g kg–1 DM) but a small decrease (–3 g kg–1 DM; +7 to –30 g kg–1 DM) at second harvest; and (iv) decreased NDF digestibility at first harvest (–6 g kg–1 NDF; +7 to –30 g kg–1 NDF) and second harvest (–23 g kg–1 NDF; –11 to –35 g kg–1 NDF). The longer growing season (+581°C‐d to +1219°C‐d) is expected to result in an additional harvest by 2040 to 2069.

Growth and Physiological Response of Timothy to Elevated Carbon Dioxide and Temperature under Contrasted Nitrogen Fertilization

ABSTRACTClimate change is expected to affect the growth and metabolism of many economically important plants including timothy (Phleum pratense L.), a major forage grass species in eastern Canada and northern Europe. Our objective was to assess the impacts of predicted increases in CO2 concentration and temperature, under contrasted N fertilization, on timothy biomass, leaf photosynthesis, and nonstructural carbohydrate concentration. Plants were grown in growth chambers under either 400 or 600 μL L−1 of CO2 and at a day/night temperature of either 22/10°C or 25/15°C, and they were fertilized with 0, 60, or 120 kg N ha−1. Two sequential harvests were taken following a 6‐wk establishment period. Elevated CO2 concentration did not affect forage biomass and increased root biomass only at first harvest, but it increased leaf photosynthesis and total soluble sugar concentration mostly when N was not limiting (120 kg N ha−1). Increased temperature reduced forage and total biomass and soluble sugar concentrations at the second harvest under 120 kg N ha−1. Combined increases of temperature and CO2 concentration (600 μL L−1 and 25/15°C) had no effect on biomass yield, but it increased leaf photosynthesis and nonstructural carbohydrates concentration compared to current conditions. Our findings show that predicted future conditions of elevated temperature and CO2 concentration will have little effect on the yield of timothy while their effect on photosynthesis and forage nonstructural concentration will depend on N availability.

Impact of climate change on harvest security and biomass yield of two timothy ley harvesting systems in Norway

SUMMARYPredicted future climate changes in northern Europe include increased air temperature and altered precipitation patterns. There is a lack of knowledge about potential climate change effects on the biomass yield and security of agricultural crops. The present study determined the potential impact of future climate change on the yield and harvest security of timothy (Phleum pratense L.). Harvest security was assessed using data on accumulated precipitation and the length of dry spell period within the 7 days after cutting. Timothy production as a function of weather, soil and management practices was simulated using the LINGRA model for the periods 1961–90, 2046–65 and 2080–99, and the locations Apelsvoll, Ås, Sola, Tromsø and Værnes in Norway and harvest systems with 600 and 800 °C days between cuts. One hundred years of daily weather data were generated with the LARS-WG tool, using future daily weather data sets based on 12 Global Climate Models. Total seasonal biomass yield varied between 690 g dry matter (DM)/m2 for the 800 °C days harvesting regime in the period 1961–90 at Tromsø and 1548 g DM/m2 for the same harvesting regime in the period 2046–65 at Sola. In general, the biomass was higher in the two future periods than in 1961–90 across locations and harvesting regimes, mainly owing to more cuts per season. Accumulated precipitation after cutting varied between 12·2 mm after the first cut for the 600 °C days harvesting regime in the period 1961–90 at Værnes and 42·5 mm after the fourth cut in the 800 °C days harvesting regime in the period 2080–99 at Sola. The longest duration of dry spell 7 days after pre-planned harvest varied between 1·8 days after the fourth cut at Sola in the 600 °C days harvesting regime for the period 2080–99, and 3·9 days after the first cut at Ås in the 800 °C days harvesting regime for the period 2046–65. Potential consequences of these results are discussed.

Assessing uncertainties in impact of climate change on grass production in Northern Europe using ensembles of global climate models

Forage-based dairy and livestock production is the backbone of agriculture in Northern Europe in economic terms. Changes in growing conditions that affect forage grass yield may have great economic consequences. This study assessed the impact of climate change on two grass species, timothy and ryegrass, at 14 locations in Northern Europe (Iceland, Scandinavia, Baltic countries) in a near-future scenario (2040–2065) compared with the baseline period 1960–1990. Local-scale climate scenarios were based on the CMIP3 multi-model ensembles of 15 global climate models in order to quantify the uncertainty in the impacts relating to highly uncertain projections of future climate. Potential yield of timothy, the most important perennial forage grass in Northern Europe, was simulated under the assumption of optimal overwintering conditions and current CO2 level, in order to obtain an estimate of the effect of changes in summer climate per se. The risk of frost and ice damage during winter was also assessed. The simulation results demonstrated that potential grass yield will increase throughout the study area, mainly as a result of increased growing temperatures. The yield response to climate change was slightly larger in irrigated than non-irrigated conditions (14% and 11%, respectively), due to larger water deficit for the 2050 scenario. However, a geo-climatic gradient was evident, with the largest predicted yield response at western locations. A geo-climatic gradient was also revealed with respect to potential frost damage, which was predicted to increase during winter in some areas east of the Baltic Sea for timothy, and for a larger number of locations both east and west of the Baltic Sea for perennial ryegrass. The risk of frost damage in spring was predicted to increase mainly in western parts of the study area. If frost damage to perennial ryegrass increases during winter, the expected increase in winter temperature due to global warming may not necessarily improve overwintering conditions, so the growing zone may not necessarily expand to the north and east of the study area by 2050. The uncertainty in impacts was frequently, but not consistently, greater in western than eastern locations.

DNA Profiling of Seed Parents and a Topcross Tester and its Application for Yield Improvement in Timothy (Phleum pratense L.)

ABSTRACTAssessment of genetic diversity based on DNA profiling contributes to the selection of superior parents for heterosis. The objective of this study was to investigate how closely the yields of timothy (Phleum pratense L.) topcross progenies are related to the genetic diversity between their seed parents and the pollen tester parent ‘Aurora’, and to predict their yield potentials from the index based on simple sequence repeat (SSR) marker polymorphisms. Genetic diversity among 67 genotypes, which consisted of 16 plants of timothy cultivar Aurora, the pollen parent for topcross testers, and 51 clones derived from breeding populations was evaluated based on 28 SSR markers carrying 408 alleles. Genetic distance (GD) was estimated for all possible pairs of genotypes and then the mean of the GD estimates between each clone and Aurora (GDA) was also assessed to find the relationship between GDA estimates and yields of topcross progenies derived from all crosses between each clone and Aurora. The GDA estimates of the clones ranged from 0.653 to 0.756, and a correlation coefficient between the GDA estimates and yields of their topcross progenies was 0.675 (p < 0.001). These results strongly suggest that GD would provide reliable information on the yields of the assumed topcross progeny lines and that it will help breeders to accelerate yield improvements for a practical breeding program of timothy.

Maximizing Timothy Forage Yield and Quality by Balanced Nitrogen, Phosphorus, and Sulfur Fertilization

A 3‐yr (2005–2007) field experiment was conducted on a Gray Luvisol (Typic Cryoboralf) loam near Star City, SK, Canada, to determine the influence of single and combined annual applications of N, P, and S fertilizers on timothy (Phleum pratense L.) forage dry matter yield (DMY), quality [concentration of crude protein (CP), nitrate N, acid detergent fiber (ADF), neutral detergent fiber (NDF), total P, and total S] and N, P, and S uptake, and residual nitrate N, extractable P, and sulfate‐S in soil. The highest DMY and nutrient uptake were obtained when N and S were applied together. Concentration of CP and total P in forage increased with application of N alone, but decreased with the addition of S along with N. Concentrations of nitrate N in forage (< 0.011 g nitrate N kg−1) were much lower than those considered potentially toxic (>2.26 g nitrate N kg−1) to livestock. Concentration of ADF and NDF in forage increased with N application. Concentration of total S in forage increased with S application, but decreased with N application. Residual soil nitrate N in 0 to 60 cm depth increased with N application, but decreased when S was applied in combination with N. Residual soil extractable P in 0 to 15 cm depth increased with P fertilizer, but decreased when N and/or S were applied in combination with P. Residual soil sulfate‐S increased with S fertilization, but usually decreased when S was applied in combination with N. In conclusion, combined applications of N and S fertilizers produced maximum forage yield and nutrient uptake of timothy, and reduced accumulation of nitrate N in this soil lacking in these nutrients.