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R J Gutteridge - One of the best experts on this subject based on the ideXlab platform.

  • effects of break crops and of wheat volunteers growing in break crops or in set aside or conservation covers all following crops of winter wheat on the development of take all gaeumannomyces graminis var tritici in succeeding crops of winter wheat
    Annals of Applied Biology, 2014
    Co-Authors: J F Jenkyn, R J Gutteridge, Robin P White
    Abstract:

    Experiments on the Rothamsted and Woburn Experimental Farms studied the effects on Take-All of different break crops and of set-aside/conservation covers that interrupted sequences of winter wheat. There was no evidence for different effects on Take-All of the break crops per se but the presence of volunteers, in crops of oilseed rape, increased the amounts of Take-All in the following wheat. Severity of Take-All was closely related to the numbers of volunteers in the preceding break crops and covers, and was affected by the date of their destruction. Early destruction of set-aside/conservation covers was usually effective in preventing damaging Take-All in the following wheat except, sometimes, when populations of volunteers were very large. The experiments were not designed to test the effects of sowing dates but different amounts of Take-All in the first wheats after breaks or covers apparently affected the severity of Take-All in the following (second) wheats only where the latter were relatively late sown. In earlier-sown second wheats, Take-All was consistently severe and unrelated to the severity of the Disease in the preceding (first) wheats. Results from two very simple experiments suggested that substituting set-aside/conservation covers for winter wheat, for 1 year only, did not seriously interfere with the development of Take-All Disease or with the development or maintenance of Take-All decline (TAD). With further research, it might be possible for growers wishing to exploit TAD to incorporate set-aside/conservation covers into their cropping strategies, and especially to avoid the worst effects of the Disease on grain yield during the early stages of epidemics.

  • identifying variation in resistance to the take all fungus gaeumannomyces graminis var tritici between different ancestral and modern wheat species
    BMC Plant Biology, 2014
    Co-Authors: V. E. Mcmillan, R J Gutteridge, K E Hammondkosack
    Abstract:

    Ancestral wheat relatives are important sources of genetic diversity for the introduction of novel traits for the improvement of modern bread wheat. In this study the aim was to assess the susceptibility of 34 accessions of the diploid wheat Triticum monococcum (A genome) to Gaeumannomyces graminis var. tritici (Ggt), the causal agent of Take-All Disease. The second aim was to explore the susceptibility of tetraploid wheat (T. durum) and the B genome progenitor species Aegilops speltoides to Ggt. Field trials, conducted over 5 years, identified seven T. monococcum accessions with a good level of resistance to Take-All when exposed to natural inoculum under UK field conditions. All other accessions were highly susceptible or did not exhibit a consistent phenotype across years. DArT marker genotyping revealed that whole genome diversity was not closely related to resistance to Take-All within T. monococcum, suggesting that multiple genetic sources of resistance may exist within the species. In contrast the tetraploid wheat cultivars and Ae. speltoides were all highly susceptible to the Disease, including those with known elevated levels of benzoxazinoids. The diploid wheat species T. monococcum may provide a genetic source of resistance to Take-All Disease that could be utilised to improve the performance of T. aestivum in high Disease risk situations. This represents an extremely valuable resource to achieve economic and sustainable genetic control of this root Disease.

  • identifying variation in resistance to the take all fungus gaeumannomyces graminis var tritici between different ancestral and modern wheat species
    BMC Plant Biology, 2014
    Co-Authors: V. E. Mcmillan, R J Gutteridge, K E Hammondkosack
    Abstract:

    Background: Ancestral wheat relatives are important sources of genetic diversity for the introduction of novel traits for the improvement of modern bread wheat. In this study the aim was to assess the susceptibility of 34 accessions of the diploid wheat Triticum monococcum (A genome) to Gaeumannomyces graminis var. tritici (Ggt), the causal agent of Take-All Disease. The second aim was to explore the susceptibility of tetraploid wheat (T. durum) and the B genome progenitor species Aegilops speltoides to Ggt. Results: Field trials, conducted over 5 years, identified seven T. monococcum accessions with a good level of resistance to Take-All when exposed to natural inoculum under UK field conditions. All other accessions were highly susceptible or did not exhibit a consistent phenotype across years. DArT marker genotyping revealed that whole genome diversity was not closely related to resistance to Take-All within T. monococcum, suggesting that multiple genetic sources of resistance may exist within the species. In contrast the tetraploid wheat cultivars and Ae. speltoides were all highly susceptible to the Disease, including those with known elevated levels of benzoxazinoids. Conclusions: The diploid wheat species T. monococcum may provide a genetic source of resistance to Take-All Disease that could be utilised to improve the performance of T. aestivum in high Disease risk situations. This represents an extremely valuable resource to achieve economic and sustainable genetic control of this root Disease.

  • the potential of non pathogenic gaeumannomyces spp occurring naturally or introduced into wheat crops or preceding crops for controlling take all in wheat
    Annals of Applied Biology, 2007
    Co-Authors: R J Gutteridge, J F Jenkyn, G L Bateman
    Abstract:

    Take-All Disease (Gaeumannomyces graminis var. tritici) in wheat crops is known to be suppressed by naturally occurring antagonistic fungi, closely related to the pathogen, that infect grasses and cereals. This form of suppression was re-investigated because of the changing importance and role of grass weeds and grass covers in arable farming. Natural populations of the competitive fungus Gaeumannomyces cylindrosporus, allowed to develop under rye-grass, were more effective than artificially introduced populations in suppressing the development of Take-All in following wheat crops. To be effective, the antagonist needs to be present before the start of wheat cropping. Introducing G. cylindrosporus, but not G. graminis var. graminis (a potential antagonist that is faster growing), into a previous crop, or just after the previous crop, sometimes suppressed Take-All, but the effect was small. It is concluded that, for any future attempts at biocontrol by these fungi, they should be introduced into a preceding crop not susceptible to Take-All. Take-All inoculum in the soil should be at a minimum and effective hosts of the Take-All pathogen must not be present as weeds or volunteers.

  • effects of sowing date and volunteers on the infectivity of soil infested with gaeumannomyces graminis var tritici and on take all Disease in successive crops of winter wheat
    Annals of Applied Biology, 2003
    Co-Authors: R J Gutteridge, D Hornby
    Abstract:

    Summary In a field experiment on winter wheat, Take-All on plants and the infectivity of the soil were studied in crop sequences with different combinations of sowing dates. Take-All was negligible in the first wheat crop, but thereafter the mean Disease intensity (measured using a Take-All rating, TAR, with a maximum of 300) was 108, 190, 118 and 251 in the second to fifth successive crops. In each growing season, the Disease differed amongst sequences and built up more rapidly and was more intense on plants sown in mid-September than on plants sown in mid-October. In late-sown plots, where volunteers had been present during the mid-September to mid-October period, Take-All reached an intensity intermediate between that in early-sown plots and that in late-sown plots that had been kept free of volunteers. Volunteers, therefore, partially offset the expected beneficial effect of decreased Disease with later sowing. Differences in Take-All amongst sequences were most pronounced in the second wheat crop and early sowing of the previous wheat increased intensity of Disease. In the following (third) crop, differences in Disease intensity amongst sequences were smaller. Soil infectivity (measured by seedling bioassay after harvest) built up progressively from a low level after the first crop to peak after the third crop. In this build-up phase, soil infectivity estimates were always numerically greater after harvest of early-sown treatments than after later-sown treatments, although never significant at P= 0.05. The greatest difference (P= 0.06) was recorded in October before sowing of the third crop, where the comparison was between soil after two previous early sowings and soil after two previous later sowings and control of volunteers. In the same autumn, presence of green cover (i.e. volunteers) was associated with a smaller loss of soil infectivity between harvest and later sowing than occurred in an absence of green cover. In 2nd–4th crops, where comparisons were available and mean TARs indicated moderate levels of Take-All, sowing later had no yield benefit, despite more Take-All and greater soil infectivity associated with early sowing. Important considerations for the management of crops at risk of Take-All are 1) choosing appropriate sowing dates to minimize Take-All or to encourage Take-All decline and 2) controlling volunteers and weed hosts where crops are sown late to minimise Take-All.

Ludivine Lassois - One of the best experts on this subject based on the ideXlab platform.

  • Impact of spatio-temporal shade dynamics on wheat growth and yield, perspectives for temperate agroforestry
    European Journal of Agronomy, 2017
    Co-Authors: Sidonie Artru, Sarah Garré, Marie Pierre Hiel, Céline Blitz-frayret, Christian Dupraz, Ludivine Lassois
    Abstract:

    A stumbling block to the adoption of silvoarable agroforestry systems is the lack of quantitative knowledge on the performance of different crops when competing for resources with trees. In North-Western Europe, light is likely to be the principal limiting resource for understorey crops, and most agronomic studies show a systematic reduction of final yield as shade increases. However the intensity of the crop response depends on both the environmental conditions and the shade characteristics. This study addressed the issue by monitoring winter wheat (Triticum aestivum L.) growth, productivity and quality under artificial shade provided by military camouflage shade-netting, and using the Hi-sAFe model to relate the artificial shade conditions to those applying in agroforestry systems. The field experiment was carried out over two consecutive years (2013–14 and 2014–15) on the experimental farm of Gembloux Agro-Bio Tech, Belgium. The shade structures recreated two shade conditions: periodic shade (PS) and continuous shade (CS), with the former using overlapping military camouflage netting to provide discontinuous light through the day, and the latter using conventional shade cloth. The experiment simulated shading from a canopy of late-flushing hybrid walnut leaves above winter wheat. Shading was imposed 16 (2013–14) and 10 (2014–15) days before flowering and retained until harvest. The crop experienced full light conditions until the maximum leaf area index stage (LAImax) had been reached. In both years, LAI followed the same dynamics between the different treatments, but in 2013–2014 an attack of the Take-All Disease (Gaeumannomyces graminis var. tritici) reduced yields overall and prevented significant treatment effects. In season 2014–15 the decrease in global radiation reaching the crop during a period of 66 days (CS: – 61% and PS: – 43%) significantly affected final yield (CS: – 45% and PS: – 25%), mainly through a reduction of the average grain weight and the number of grain per m2. Grain protein content increased by up to 45% under the CS treatment in 2015. Nevertheless, at the plot scale, protein yield (t/ha) did not compensate for the final grain yield decrease. The Hi-sAFe model was used to simulate an agroforestry plot with two lines of walnut trees running either north-south or east-west. The levels of artificial shade levels applied in this experiment were compared to those predicted beneath trees growing with similar climatic conditions in Belgium. The levels used in the CS treatment are only likely to occur real agroforestry conditions on 10% of the cropped area until the trees are 30 years old and only with east-west tree row orientation.

Sidonie Artru - One of the best experts on this subject based on the ideXlab platform.

  • Impact of spatio-temporal shade dynamics on wheat growth and yield, perspectives for temperate agroforestry
    European Journal of Agronomy, 2017
    Co-Authors: Sidonie Artru, Sarah Garré, Marie Pierre Hiel, Céline Blitz-frayret, Christian Dupraz, Ludivine Lassois
    Abstract:

    A stumbling block to the adoption of silvoarable agroforestry systems is the lack of quantitative knowledge on the performance of different crops when competing for resources with trees. In North-Western Europe, light is likely to be the principal limiting resource for understorey crops, and most agronomic studies show a systematic reduction of final yield as shade increases. However the intensity of the crop response depends on both the environmental conditions and the shade characteristics. This study addressed the issue by monitoring winter wheat (Triticum aestivum L.) growth, productivity and quality under artificial shade provided by military camouflage shade-netting, and using the Hi-sAFe model to relate the artificial shade conditions to those applying in agroforestry systems. The field experiment was carried out over two consecutive years (2013–14 and 2014–15) on the experimental farm of Gembloux Agro-Bio Tech, Belgium. The shade structures recreated two shade conditions: periodic shade (PS) and continuous shade (CS), with the former using overlapping military camouflage netting to provide discontinuous light through the day, and the latter using conventional shade cloth. The experiment simulated shading from a canopy of late-flushing hybrid walnut leaves above winter wheat. Shading was imposed 16 (2013–14) and 10 (2014–15) days before flowering and retained until harvest. The crop experienced full light conditions until the maximum leaf area index stage (LAImax) had been reached. In both years, LAI followed the same dynamics between the different treatments, but in 2013–2014 an attack of the Take-All Disease (Gaeumannomyces graminis var. tritici) reduced yields overall and prevented significant treatment effects. In season 2014–15 the decrease in global radiation reaching the crop during a period of 66 days (CS: – 61% and PS: – 43%) significantly affected final yield (CS: – 45% and PS: – 25%), mainly through a reduction of the average grain weight and the number of grain per m2. Grain protein content increased by up to 45% under the CS treatment in 2015. Nevertheless, at the plot scale, protein yield (t/ha) did not compensate for the final grain yield decrease. The Hi-sAFe model was used to simulate an agroforestry plot with two lines of walnut trees running either north-south or east-west. The levels of artificial shade levels applied in this experiment were compared to those predicted beneath trees growing with similar climatic conditions in Belgium. The levels used in the CS treatment are only likely to occur real agroforestry conditions on 10% of the cropped area until the trees are 30 years old and only with east-west tree row orientation.

Yun Ling - One of the best experts on this subject based on the ideXlab platform.

Marie Pierre Hiel - One of the best experts on this subject based on the ideXlab platform.

  • Impact of spatio-temporal shade dynamics on wheat growth and yield, perspectives for temperate agroforestry
    European Journal of Agronomy, 2017
    Co-Authors: Sidonie Artru, Sarah Garré, Marie Pierre Hiel, Céline Blitz-frayret, Christian Dupraz, Ludivine Lassois
    Abstract:

    A stumbling block to the adoption of silvoarable agroforestry systems is the lack of quantitative knowledge on the performance of different crops when competing for resources with trees. In North-Western Europe, light is likely to be the principal limiting resource for understorey crops, and most agronomic studies show a systematic reduction of final yield as shade increases. However the intensity of the crop response depends on both the environmental conditions and the shade characteristics. This study addressed the issue by monitoring winter wheat (Triticum aestivum L.) growth, productivity and quality under artificial shade provided by military camouflage shade-netting, and using the Hi-sAFe model to relate the artificial shade conditions to those applying in agroforestry systems. The field experiment was carried out over two consecutive years (2013–14 and 2014–15) on the experimental farm of Gembloux Agro-Bio Tech, Belgium. The shade structures recreated two shade conditions: periodic shade (PS) and continuous shade (CS), with the former using overlapping military camouflage netting to provide discontinuous light through the day, and the latter using conventional shade cloth. The experiment simulated shading from a canopy of late-flushing hybrid walnut leaves above winter wheat. Shading was imposed 16 (2013–14) and 10 (2014–15) days before flowering and retained until harvest. The crop experienced full light conditions until the maximum leaf area index stage (LAImax) had been reached. In both years, LAI followed the same dynamics between the different treatments, but in 2013–2014 an attack of the Take-All Disease (Gaeumannomyces graminis var. tritici) reduced yields overall and prevented significant treatment effects. In season 2014–15 the decrease in global radiation reaching the crop during a period of 66 days (CS: – 61% and PS: – 43%) significantly affected final yield (CS: – 45% and PS: – 25%), mainly through a reduction of the average grain weight and the number of grain per m2. Grain protein content increased by up to 45% under the CS treatment in 2015. Nevertheless, at the plot scale, protein yield (t/ha) did not compensate for the final grain yield decrease. The Hi-sAFe model was used to simulate an agroforestry plot with two lines of walnut trees running either north-south or east-west. The levels of artificial shade levels applied in this experiment were compared to those predicted beneath trees growing with similar climatic conditions in Belgium. The levels used in the CS treatment are only likely to occur real agroforestry conditions on 10% of the cropped area until the trees are 30 years old and only with east-west tree row orientation.

  • Impact of spatio-temporal shade dynamics on wheat growth and yield, perspectives for temperate agroforestry
    2017
    Co-Authors: Artru S., Marie Pierre Hiel, Garré S., Dupraz C., Blitz-frayet Céline, Lassois Ludivine
    Abstract:

    A stumbling block to the adoption of silvoarable agroforestry systems is the lack of quantitative knowledge on the performance of different crops when competing for resources with trees. In North-Western Europe, light is likely to be the principal limiting resource for understorey crops, and most agronomic studies show a systematic reduction of final yield as shade increases. However the intensity of the crop response depends on both the environmental conditions and the shade characteristics. This study addressed the issue by monitoring winter wheat (Triticum aestivum L.) growth, productivity and quality under artificial shade provided by military camouflage shade-netting, and using the Hi-sAFe model to relate the artificial shade conditions to those applying in agroforestry systems. The field experiment was carried out over two consecutive years (2013–14 and 2014–15) on the experimental farm of Gembloux Agro-Bio Tech, Belgium. The shade structures recreated two shade conditions: periodic shade (PS) and continuous shade (CS), with the former using overlapping military camouflage netting to provide discontinuous light through the day, and the latter using conventional shade cloth. The experiment simulated shading from a canopy of late-flushing hybrid walnut leaves above winter wheat. Shading was imposed 16 (2013–14) and 10 (2014–15) days before flowering and retained until harvest. The crop experienced full light conditions until the maximum leaf area index stage (LAImax) had been reached. In both years, LAI followed the same dynamics between the different treatments, but in 2013–2014 an attack of the Take-All Disease (Gaeumannomyces graminis var. tritici) reduced yields overall and prevented significant treatment effects. In season 2014–15 the decrease in global radiation reaching the crop during a period of 66 days (CS: – 61% and PS: – 43%) significantly affected final yield (CS: – 45% and PS: – 25%), mainly through a reduction of the average grain weight and the number of grain per m2. Grain protein content increased by up to 45% under the CS treatment in 2015. Nevertheless, at the plot scale, protein yield (t/ha) did not compensate for the final grain yield decrease. The Hi-sAFe model was used to simulate an agroforestry plot with two lines of walnut trees running either north-south or east-west. The levels of artificial shade levels applied in this experiment were compared to those predicted beneath trees growing with similar climatic conditions in Belgium. The levels used in the CS treatment are only likely to occur real agroforestry conditions on 10% of the cropped area until the trees are 30 years old and only with east-west tree row orientation.Peer reviewe