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Richard W. Smiley - One of the best experts on this subject based on the ideXlab platform.
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Spring Barley resistance and tolerance to the cereal cyst nematode heterodera avenae
Plant Disease, 2016Co-Authors: Juliet M. Marshall, Richard W. SmileyAbstract:Heterodera avenae is a cereal cyst nematode that reduces wheat yields in the Pacific Northwest of the United States. Barley is also susceptible but there were no previous reports of resistance or tolerance to H. avenae in the United States. Spring Barley cultivars were assayed in H. avenae-infested fields over 2 years. Cultivars were planted in plots treated or not treated with aldicarb. Forty-five cultivars were evaluated for the market classes of two- and six-row feed Barley cultivars and two- and six-row malt Barley cultivars. One two-row feed Barley ('Lenetah') was ranked as resistant and four were tolerant or very tolerant. In total, 1 two-row malt Barley ('Odyssey') was very resistant and 10 were tolerant or very tolerant. Two six-row feed and two six-row malt Barley cultivars were tolerant or very tolerant but none were resistant. Seven feed Barley cultivars were ranked as having a balance of at least moderate resistance plus moderate tolerance: 'Champion', Lenetah, 'Xena', 'Idagold II', 'Transit', 'Millennium', and 'Goldeneye'. This is the first report of resistance and tolerance of Barley in H. avenae-infested fields in the Pacific Northwest. Barley productivity can be improved by planting resistant plus tolerant cultivars or by using highly resistant and highly tolerant cultivars as parents in Barley improvement programs.
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Spring Barley Resistance and Tolerance to the Cereal Cyst Nematode Heterodera avenae.
Plant Disease, 2015Co-Authors: Juliet M. Marshall, Richard W. SmileyAbstract:Heterodera avenae is a cereal cyst nematode that reduces wheat yields in the Pacific Northwest of the United States. Barley is also susceptible but there were no previous reports of resistance or tolerance to H. avenae in the United States. Spring Barley cultivars were assayed in H. avenae-infested fields over 2 years. Cultivars were planted in plots treated or not treated with aldicarb. Forty-five cultivars were evaluated for the market classes of two- and six-row feed Barley cultivars and two- and six-row malt Barley cultivars. One two-row feed Barley (‘Lenetah’) was ranked as resistant and four were tolerant or very tolerant. In total, 1 two-row malt Barley (‘Odyssey’) was very resistant and 10 were tolerant or very tolerant. Two six-row feed and two six-row malt Barley cultivars were tolerant or very tolerant but none were resistant. Seven feed Barley cultivars were ranked as having a balance of at least moderate resistance plus moderate tolerance: ‘Champion’, Lenetah, ‘Xena’, ‘Idagold II’, ‘Transit’,...
Jorgen E Olesen - One of the best experts on this subject based on the ideXlab platform.
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do soil organic carbon levels affect potential yields and nitrogen use efficiency an analysis of winter wheat and Spring Barley field trials
European Journal of Agronomy, 2015Co-Authors: Myles Oelofse, Jorgen E Olesen, Bo Markussen, Leif Knudsen, Kirsten Schelde, Lars Stoumann Jensen, Sander BruunAbstract:Abstract Soil organic carbon (SOC) is broadly recognised as an important parameter affecting soil quality, and can therefore contribute to improving a number of soil properties that influence crop yield. Previous research generally indicates that soil organic carbon has positive effects on crop yields, but in many studies it is difficult to separate the effect of nutrients from the effect of SOC in itself. The aim of this study was to analyze whether the SOC content, in itself, has a significant effect on potential yields of commonly grown cereals across a wider range of soil types in Denmark. The study draws on historical data sets from the Danish national field trials consisting of 560 winter wheat ( Triticum aestivum L.) trials and 309 Spring Barley ( Hordeum vulgare L.) trials conducted over the past 20 and 17 years, respectively. We hypothesised that for these two crops, the potential grain yield, the yield with no fertiliser N application and the N use efficiency would be positively affected by SOC level. A statistical model was developed to explore relationships between SOC and potential yield, yields at zero N application and N use efficiency (NUE). The model included a variety of variables and aimed to elucidate the sole effect of SOC by controlling for potential confounding variables. No significant effect of SOC on potential winter wheat was found, whilst for Spring Barley, only for the course sandy loam soil type was a borderline significantly positive effect of SOC on potential yields found. The relationship between unfertilized plot yields and SOC was positive for winter wheat, although not significant, whilst for Spring Barley a significant positive effect of SOC was found only for the coarse sandy soil type, and a borderline significant positive effect of SOC was found for the coarse sandy loam soil type. A significant negative relationship was found between SOC and NUE for both winter wheat and Spring Barley. Based on the large dataset analyzed, we cautiously challenge the importance of SOC in contributing to crop productivity in contexts with similar soils and climate, and we speculate that in situations where nutrient limitation does not occur, SOC levels above 1% may be sufficient to sustain yields. In light of the findings presented in this study, further work should be conducted which can further elucidate the effect of SOC on yields.
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effects of catch crop type and root depth on nitrogen leaching and yield of Spring Barley
Field Crops Research, 2012Co-Authors: Margrethe Askegaard, Tek B Sapkota, Mette Laegdsmand, Jorgen E OlesenAbstract:Abstract Catch crop root growth and nitrogen (N) uptake from both shallow and deeper soil layers are important for N management in arable farming systems, particularly in climates where excess winter precipitation induces N leaching. We simulated the root growth and biomass yield of three common catch crops [chicory (Cichorium intybus L.), fodder radish (Raphanus sativus L.) and perennial ryegrass (Lolium perenne L.)] and their effect on soil mineral N (NO3− and NH4+) in different soil layers by using the FASSET model. The simulated results of catch crop biomass and root growth and mineral N in the soil profile were validated against two years (2006 and 2007) of observations taken in Foulum and Flakkebjerg, Denmark. Once the model was validated, the effect of these three catch crops on N leaching and grain yield of Spring Barley monoculture was simulated for 30 years. Both measurements and model simulations showed that fodder radish developed the deepest root system and depleted N from deeper soil layers than chicory and ryegrass. Thirty years of simulations showed that the system with ryegrass catch crop had a smaller amount of N leaching from 1 m depth than the system with other catch crops and without catch crops. However, estimated total N leached at 2 m soil depth was smallest in the system with fodder radish followed by the system with chicory, indicating that these catch crops are capable of taking soil N also from below 1 m depth. On average, the system with fodder radish was estimated to decrease N leaching from 2 m depth by 79% compared with the system without catch crops, resulting in an average Spring Barley grain yield increase of 2%. Chicory and ryegrass correspondingly contributed to reducing N leaching from 2 m soil depths by 71 and 67% when compared with the system without catch crop. The system planted to chicory and ryegrass catch crops decreased Spring Barley yield by 3 and 5%, respectively, probably because of competition between the cereal crop and the catch crop for N, water and light. Discontinuation of catch crop use increased slightly not only the Spring Barley yield but also N leaching by about 17%. Inclusion of catch crop in the system increased soil total N and C content by 16–46 kg N ha−1 year−1 and 170–498 kg C ha−1 year−1, respectively, as compared to the system without catch crop. The increase was largest with the use of ryegrass catch crop.
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soil tillage enhanced co2 and n2o emissions from loamy sand soil under Spring Barley
Soil & Tillage Research, 2007Co-Authors: Dmitri Chatskikh, Jorgen E OlesenAbstract:Abstract Soil tillage intensity can be expected to affect the greenhouse gas balance of arable cropping systems through effects on soil physics and biology affecting soil carbon storage and nitrous oxide (N 2 O) emissions. The effects of conventional tillage (CT) with ploughing to 20 cm, reduced tillage (RT) with harrowing to 8–10 cm and direct drilling (DD) on CO 2 and N 2 O emissions from a loamy sand soil (8.1% clay, 3.5% organic matter) under Spring Barley undersown with ryegrass were measured by static chambers over a period of 113 days in Spring and summer 2004 in a tillage experiment established in 2002 at Foulum, Denmark. There was a high temporal and spatial variation in both CO 2 and N 2 O emissions, which made the comparisons of treatment effects on emissions on single dates difficult. However, this variation was reduced when the measurements were corrected for diurnal variation in the emissions and when emissions were cumulated over a longer period. Both CO 2 and N 2 O emissions decreased in the order CT > RT > DD. Compared with CT (40 kg C day −1 ) the cumulated CO 2 emissions during the 91 days after tillage were 21 and 25% lower for the RT and the DD treatments, respectively. The cumulated N 2 O emission from CT over the entire observation period (0.89 kg N ha −1 or 7.9 g N day −1 ) was about twice that of DD. The N 2 O emissions were significantly higher for CT compared with DD and RT, even before tillage and the difference increased after tillage, but decreased after fertilisation. Spring Barley dry matter grain yields were reduced by 14% for RT and 27% for DD compared to CT. Measurements of soil mineral nitrogen (N) at sowing showed no difference between the treatments, and could thus not explain the differences in N 2 O emissions and crop N uptake. It is likely that tillage affected CO 2 emissions, N 2 O emissions and crop growth through different processes, where effects of soil compactness on root penetration and soil aeration and diffusivity on one side and soil organic matter turnover on the other side probably played key roles.
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the value of catch crops and organic manures for Spring Barley in organic arable farming
Field Crops Research, 2007Co-Authors: Jorgen E Olesen, Margrethe Askegaard, E M Hansen, Ilse A RasmussenAbstract:Abstract The effect of nitrogen (N) supply and weeds on grain yield of Spring Barley was investigated from 1997 to 2004 in an organic farming crop rotation experiment in Denmark on three different soil types varying from coarse sand to sandy loam. Two experimental factors were included in the experiment in a factorial design: (1) catch crop (with and without), and (2) manure (with and without). The crop rotation included grass-clover as a green manure crop. Animal manure was applied as slurry in rates corresponding to 40% of the N demand of the cereal crops. Application of 50 kg NH 4 -N ha −1 in manure (slurry) increased average Barley grain DM yield by 1.0–1.3 Mg DM ha −1 , whereas the use of catch crops (primarily perennial ryegrass) increased grain DM yield by 0.2–0.4 Mg DM ha −1 with the smallest effect on the loamy sand and sandy loam soils and the greatest effect on the coarse sandy soil. Model estimations showed that the average yield reduction from weeds varied from 0.2 to 0.4 Mg DM ha −1 depending on weed species and density. The yield effects of N supply were more predictable and less variable than the effects of weed infestation. The infestation level of leaf diseases was low and not a significant source of yield variation. The apparent recovery efficiency of N in grains (N use efficiency, NUE) from NH 4 -N in applied manure varied from 29 to 38%. The NUE of above-ground N in catch crops sampled in November prior to the Spring Barley varied from 16 to 52% with the largest value on the coarse sandy soil and the smallest value on the sandy loam soil. A comparison of grain yield levels obtained at the different locations with changes in soil organic matter indicated a NUE of 21–26% for soil N mineralisation, which is smaller than that for the mineral N applied in manure. However, this estimate is uncertain and further studies are needed to quantify differences in NUE from various sources of N. The proportion of perennial weeds in total biomass increased during the experiment, particularly in treatments without manure application. The results show that manure application is a key factor in maintaining good crop yields in arable organic farming on sandy soils, and in securing crops that are sufficiently competitive against perennial weeds.
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the value of catch crops and organic manures for Spring Barley in organic arable farming
Field Crops Research, 2007Co-Authors: Jorgen E Olesen, Margrethe Askegaard, E M Hansen, Ilse A RasmussenAbstract:The effect of nitrogen (N) supply and weeds on grain yield of Spring Barley was investigated in an organic farming crop rotation experiment on three different soil types in Denmark from 1997 to 2001. Three experimental factors were included in the experiment in a factorial design: 1) crop rotation (lupin or pea/Barley as previous crop to Barley), 2) cover crop (with and without), and 3) manure (with and without). The crop rotations included grass-clover as a green manure crop. Animal manure was applied as slurry in rates corresponding to 40% of the N demand of the cereal crops. Application of 50 kg NH4-N ha-1 in manure (slurry) increased Barley grain DM yield by 1.0 to 1.3 Mg DM ha-1, whereas the use of cover crops (primarily perennial ryegrass) increased grain DM yield by 0.4 to 0.7 Mg DM ha-1 with the smallest effect on the sandy loam soil and the highest effect on the coarse sandy soil. Model estimations showed that the yield reduction from weeds varied from 0.3 to 1.6 Mg DM ha-1 depending on weed species and density. The yield effects of N supply were thus more predictable and less variable than the effects of weed infestation. The N use efficiency of NH4-N in applied manure varied from 25 to 39% corresponding to N use efficiencies obtained with mineral N fertilisers. The N use efficiency of above-ground weeds and cover crops sampled in November prior to the Spring Barley varied from 13 to 57%. Pea/Barley and lupin increased grain yield by 0.2 and 0.8 Mg DM ha-1 over winter wheat as a previous crop. This could not be explained by N in the above-ground residues of the previous crop. Grass-clover as a green manure crop three years prior to the Spring Barley increased grain yield by about 0.5 Mg DM ha-1 at Flakkebjerg. Cropping history was thus equally important for grain yield as manure application.
Ewa A Czyz - One of the best experts on this subject based on the ideXlab platform.
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effects of traffic on soil aeration bulk density and growth of Spring Barley
Soil & Tillage Research, 2004Co-Authors: Ewa A CzyzAbstract:Abstract This paper reports the results of field experiments on several different soils to quantify the effects of different numbers of passes of vehicular traffic on soil aeration status (measured in terms of oxygen diffusion rate, ODR and redox potential, Eh), soil bulk density and development of Spring Barley. In a further series of field experiments, the effects of single and dual wheels were compared and the effectiveness of a soil loosener operating behind the wheels was evaluated. Additionally, some microplot experiments are reported in which a range of known values of soil bulk density were produced and the effects on soil aeration and development of Spring Barley were evaluated. It is shown that repeated wheeling, even by a tractor of only about 2 tonnes weight, can produce soil conditions in which aeration can be limiting for crop growth. The use of dual wheels resulted in lower values of soil bulk density and associated greater soil aeration. The loosener alleviated the compaction produced by wheels and also improved soil aeration. For a sandy loam soil, greatest root growth and crop yield occurred at a bulk density of 1.43 Mg m −3 . Soil aeration as a component of soil physical quality is discussed.
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effects of traffic on soil aeration bulk density and growth of Spring Barley
Soil & Tillage Research, 2004Co-Authors: Ewa A CzyzAbstract:Abstract This paper reports the results of field experiments on several different soils to quantify the effects of different numbers of passes of vehicular traffic on soil aeration status (measured in terms of oxygen diffusion rate, ODR and redox potential, Eh), soil bulk density and development of Spring Barley. In a further series of field experiments, the effects of single and dual wheels were compared and the effectiveness of a soil loosener operating behind the wheels was evaluated. Additionally, some microplot experiments are reported in which a range of known values of soil bulk density were produced and the effects on soil aeration and development of Spring Barley were evaluated. It is shown that repeated wheeling, even by a tractor of only about 2 tonnes weight, can produce soil conditions in which aeration can be limiting for crop growth. The use of dual wheels resulted in lower values of soil bulk density and associated greater soil aeration. The loosener alleviated the compaction produced by wheels and also improved soil aeration. For a sandy loam soil, greatest root growth and crop yield occurred at a bulk density of 1.43 Mg m −3 . Soil aeration as a component of soil physical quality is discussed.
Juliet M. Marshall - One of the best experts on this subject based on the ideXlab platform.
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Spring Barley resistance and tolerance to the cereal cyst nematode heterodera avenae
Plant Disease, 2016Co-Authors: Juliet M. Marshall, Richard W. SmileyAbstract:Heterodera avenae is a cereal cyst nematode that reduces wheat yields in the Pacific Northwest of the United States. Barley is also susceptible but there were no previous reports of resistance or tolerance to H. avenae in the United States. Spring Barley cultivars were assayed in H. avenae-infested fields over 2 years. Cultivars were planted in plots treated or not treated with aldicarb. Forty-five cultivars were evaluated for the market classes of two- and six-row feed Barley cultivars and two- and six-row malt Barley cultivars. One two-row feed Barley ('Lenetah') was ranked as resistant and four were tolerant or very tolerant. In total, 1 two-row malt Barley ('Odyssey') was very resistant and 10 were tolerant or very tolerant. Two six-row feed and two six-row malt Barley cultivars were tolerant or very tolerant but none were resistant. Seven feed Barley cultivars were ranked as having a balance of at least moderate resistance plus moderate tolerance: 'Champion', Lenetah, 'Xena', 'Idagold II', 'Transit', 'Millennium', and 'Goldeneye'. This is the first report of resistance and tolerance of Barley in H. avenae-infested fields in the Pacific Northwest. Barley productivity can be improved by planting resistant plus tolerant cultivars or by using highly resistant and highly tolerant cultivars as parents in Barley improvement programs.
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Spring Barley Resistance and Tolerance to the Cereal Cyst Nematode Heterodera avenae.
Plant Disease, 2015Co-Authors: Juliet M. Marshall, Richard W. SmileyAbstract:Heterodera avenae is a cereal cyst nematode that reduces wheat yields in the Pacific Northwest of the United States. Barley is also susceptible but there were no previous reports of resistance or tolerance to H. avenae in the United States. Spring Barley cultivars were assayed in H. avenae-infested fields over 2 years. Cultivars were planted in plots treated or not treated with aldicarb. Forty-five cultivars were evaluated for the market classes of two- and six-row feed Barley cultivars and two- and six-row malt Barley cultivars. One two-row feed Barley (‘Lenetah’) was ranked as resistant and four were tolerant or very tolerant. In total, 1 two-row malt Barley (‘Odyssey’) was very resistant and 10 were tolerant or very tolerant. Two six-row feed and two six-row malt Barley cultivars were tolerant or very tolerant but none were resistant. Seven feed Barley cultivars were ranked as having a balance of at least moderate resistance plus moderate tolerance: ‘Champion’, Lenetah, ‘Xena’, ‘Idagold II’, ‘Transit’,...
Tek B Sapkota - One of the best experts on this subject based on the ideXlab platform.
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effects of catch crop type and root depth on nitrogen leaching and yield of Spring Barley
Field Crops Research, 2012Co-Authors: Margrethe Askegaard, Tek B Sapkota, Mette Laegdsmand, Jorgen E OlesenAbstract:Abstract Catch crop root growth and nitrogen (N) uptake from both shallow and deeper soil layers are important for N management in arable farming systems, particularly in climates where excess winter precipitation induces N leaching. We simulated the root growth and biomass yield of three common catch crops [chicory (Cichorium intybus L.), fodder radish (Raphanus sativus L.) and perennial ryegrass (Lolium perenne L.)] and their effect on soil mineral N (NO3− and NH4+) in different soil layers by using the FASSET model. The simulated results of catch crop biomass and root growth and mineral N in the soil profile were validated against two years (2006 and 2007) of observations taken in Foulum and Flakkebjerg, Denmark. Once the model was validated, the effect of these three catch crops on N leaching and grain yield of Spring Barley monoculture was simulated for 30 years. Both measurements and model simulations showed that fodder radish developed the deepest root system and depleted N from deeper soil layers than chicory and ryegrass. Thirty years of simulations showed that the system with ryegrass catch crop had a smaller amount of N leaching from 1 m depth than the system with other catch crops and without catch crops. However, estimated total N leached at 2 m soil depth was smallest in the system with fodder radish followed by the system with chicory, indicating that these catch crops are capable of taking soil N also from below 1 m depth. On average, the system with fodder radish was estimated to decrease N leaching from 2 m depth by 79% compared with the system without catch crops, resulting in an average Spring Barley grain yield increase of 2%. Chicory and ryegrass correspondingly contributed to reducing N leaching from 2 m soil depths by 71 and 67% when compared with the system without catch crop. The system planted to chicory and ryegrass catch crops decreased Spring Barley yield by 3 and 5%, respectively, probably because of competition between the cereal crop and the catch crop for N, water and light. Discontinuation of catch crop use increased slightly not only the Spring Barley yield but also N leaching by about 17%. Inclusion of catch crop in the system increased soil total N and C content by 16–46 kg N ha−1 year−1 and 170–498 kg C ha−1 year−1, respectively, as compared to the system without catch crop. The increase was largest with the use of ryegrass catch crop.
