toggle visibility Search & Display Options

Select All    Deselect All
 |   | 
Details
   print
  Records Links
Author Müller, C. doi  openurl
  Title African lessons on climate change risks for agriculture Type Journal Article
  Year 2013 Publication Annual Review of Nutrition Abbreviated Journal Ann. Rev. Nutr.  
  Volume 33 Issue 1 Pages 395-411  
  Keywords Africa/epidemiology; *Climate Change/economics; Crops, Agricultural/economics/*growth & development; Diet/adverse effects/economics; Forecasting; *Global Health/economics/trends; Humans; Malnutrition/economics/epidemiology/prevention & control; *Models, Theoretical; Risk; Soil/chemistry; Water Resources/economics  
  Abstract Climate change impact assessments on agriculture are subject to large uncertainties, as demonstrated in the present review of recent studies for Africa. There are multiple reasons for differences in projections, including uncertainties in greenhouse gas emissions and patterns of climate change; assumptions on future management, aggregation, and spatial extent; and methodological differences. Still, all projections agree that climate change poses a significant risk to African agriculture. Most projections also see the possibility of increasing agricultural production under climate change, especially if suitable adaptation measures are assumed. Climate change is not the only projected pressure on African agriculture, which struggles to meet demand today and may need to feed an additional one billion individuals by 2050. Development strategies are urgently needed, but they will need to consider future climate change and its inherent uncertainties. Science needs to show how existing synergies between climate change adaptation and development can be exploited.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0199-9885 1545-4312 ISBN Medium Article  
  Area Expedition Conference  
  Notes (up) CropM Approved no  
  Call Number MA @ admin @ Serial 4496  
Permanent link to this record
 

 
Author Morales, I.; Diaz, B.M.; Hermoso De Mendoza, A.; Nebreda, M.; Fereres, A. url  doi
openurl 
  Title The Development of an Economic Threshold for Nasonovia ribisnigri (Hemiptera: Aphididae) on Lettuce in Central Spain Type Journal Article
  Year 2013 Publication Journal of Economic Entomology Abbreviated Journal J. Econ. Entomol.  
  Volume 106 Issue 2 Pages 891-898  
  Keywords Animals; Aphids/*physiology; Insect Control/economics/methods; Insecticides/administration & dosage; Lettuce/*growth & development; Nitriles/administration & dosage; Nonlinear Dynamics; Population Density; Pyrethrins/administration & dosage; Seasons; Spain  
  Abstract This study reports economic thresholds for the lettuce aphid Nasonovia ribisnigri (Mosley), based exclusively on cosmetic damage, that is, presence or absence of aphids at harvest time. Field trials were conducted in La Poveda Experimental Farm, Madrid (Spain) during autumn (2004 and 2005) and spring (2005 and 2006). Plants were arranged in plots and just before the formation of lettuce hearts they were infested with different densities of N. ribisnigri. Two days later, half of each plot was treated with tau-fluvalinate (Klartan24AF) and the other half remained as an untreated control. Economic thresholds were obtained from nonlinear regressions calculated between the percentage of commercial plants at the end of the crop cycle for both, treated and untreated semiplots, and the different initial densities of N. ribisnigri per plant. Two criteria were used to consider a commercial lettuce plant: a conservative estimate (0 aphids/plant) and a lax one (< 5 aphids/plant). Thus, an economic threshold was established for each season and criterium. The economic thresholds that were obtained with the most and least conservative criteria were in spring 0.06 and 0.12 aphids per plant, and in autumn 0.07 and 0.13 aphids per plant, respectively. These results show that to avoid cosmetic damage, insecticide sprays are required when a very low aphid density is detected in lettuce seedlings soon after transplant.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-0493 ISBN Medium Article  
  Area Expedition Conference  
  Notes (up) CropM Approved no  
  Call Number MA @ admin @ Serial 4497  
Permanent link to this record
 

 
Author Legarrea, S.; Betancourt, M.; Plaza, M.; Fraile, A.; García-Arenal, F.; Fereres, A. doi  openurl
  Title Dynamics of nonpersistent aphid-borne viruses in lettuce crops covered with UV-absorbing nets Type Journal Article
  Year 2012 Publication Virus Research Abbreviated Journal Virus Res.  
  Volume 165 Issue 1 Pages 1-8  
  Keywords Absorption; Animals; Aphids/growth & development/radiation effects/*virology; Insect Control/instrumentation/*methods; Insect Vectors/growth & development/radiation effects/*virology; Lettuce/parasitology/*virology; Plant Diseases/prevention & control/*virology; Plant Viruses/*physiology; Protective Devices/virology; Ultraviolet Rays  
  Abstract Aphid-transmitted viruses frequently cause severe epidemics in lettuce grown under Mediterranean climates. Spatio-temporal dynamics of aphid-transmitted viruses and its vector were studied on lettuce (Lactuca sativa L.) grown under tunnels covered by two types of nets: a commercial UV-absorbing net (Bionet) and a Standard net. A group of plants infected by Cucumber mosaic virus (CMV, family Bromoviridae, genus Cucumovirus) and Lettuce mosaic virus (LMV, family Potyviridae, genus Potyvirus) was transplanted in each plot. The same virus-infected source plants were artificially infested by the aphid Macrosiphum euphorbiae (Thomas). Secondary spread of insects was weekly monitored and plants were sampled for the detection of viruses every two weeks. In 2008, the infection rate of both CMV and LMV were lower under the Bionet than under the Standard cover, probably due to the lower population density and lower dispersal rate achieved by M. euphorbiae. However, during spring of 2009, significant differences in the rate of infection between the two covers were only found for LMV six weeks after transplant. The spatial distribution of the viruses analysed by SADIE methodology was “at random”, and it was not associated to the spatial pattern of the vector. The results obtained are discussed analyzing the wide range of interactions that occurred among UV-radiation, host plant, viruses, insect vector and environmental conditions. Our results show that UV-absorbing nets can be recommended as a component of an integrated disease management program to reduce secondary spread of lettuce viruses, although not as a control measure on its own.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0168-1702 ISBN Medium Article  
  Area Expedition Conference  
  Notes (up) CropM Approved no  
  Call Number MA @ admin @ Serial 4475  
Permanent link to this record
 

 
Author Rötter, R.P.; Tao, F.; Höhn, J.G.; Palosuo, T. url  doi
openurl 
  Title Use of crop simulation modelling to aid ideotype design of future cereal cultivars Type Journal Article
  Year 2015 Publication Journal of Experimental Botany Abbreviated Journal J. Experim. Bot.  
  Volume 66 Issue 12 Pages 3463-3476  
  Keywords Breeding/*methods; Climate Change; *Computer Simulation; Ecotype; Edible Grain/*growth & development; *Models, Theoretical; cereals; climate extremes; crop growth simulation; ensemble modelling; future cultivars; genetic modelling; ideotype breeding; model improvement; model-aided design  
  Abstract A major challenge of the 21st century is to achieve food supply security under a changing climate and roughly a doubling in food demand by 2050 compared to present, the majority of which needs to be met by the cereals wheat, rice, maize, and barley. Future harvests are expected to be especially threatened through increased frequency and severity of extreme events, such as heat waves and drought, that pose particular challenges to plant breeders and crop scientists. Process-based crop models developed for simulating interactions between genotype, environment, and management are widely applied to assess impacts of environmental change on crop yield potentials, phenology, water use, etc. During the last decades, crop simulation has become important for supporting plant breeding, in particular in designing ideotypes, i.e. ‘model plants’, for different crops and cultivation environments. In this review we (i) examine the main limitations of crop simulation modelling for supporting ideotype breeding, (ii) describe developments in cultivar traits in response to climate variations, and (iii) present examples of how crop simulation has supported evaluation and design of cereal cultivars for future conditions. An early success story for rice demonstrates the potential of crop simulation modelling for ideotype breeding. Combining conventional crop simulation with new breeding methods and genetic modelling holds promise to accelerate delivery of future cereal cultivars for different environments. Robustness of model-aided ideotype design can further be enhanced through continued improvements of simulation models to better capture effects of extremes and the use of multi-model ensembles.  
  Address 2016-10-31  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0022-0957 1460-2431 ISBN Medium Review  
  Area Expedition Conference  
  Notes (up) CropM, ft_macsur Approved no  
  Call Number MA @ admin @ Serial 4804  
Permanent link to this record
 

 
Author Zhao, G.; Siebert, S.; Enders, A.; Rezaei, E.E.; Yan, C.; Ewert, F. url  doi
openurl 
  Title Demand for multi-scale weather data for regional crop modeling Type Journal Article
  Year 2015 Publication Agricultural and Forest Meteorology Abbreviated Journal Agricultural and Forest Meteorology  
  Volume 200 Issue Pages 156-171  
  Keywords multi-scale; spatial heterogeneity; spatial resolution; crop model; climate variability; climate-change scenarios; integrated assessment; large-scale; phenological development; agricultural systems; spatial-resolution; data aggregation; european-union; winter-wheat; input data  
  Abstract A spatial resolution needs to be determined prior to using models to simulate crop yields at a regional scale, but a dilemma exists in compromising between different demands. A fine spatial resolution demands extensive computation load for input data assembly, model runs, and output analysis. A coarse spatial resolution could result in loss of spatial detail in variability. This paper studied the impact of spatial resolution, data aggregation and spatial heterogeneity of weather data on simulations of crop yields, thus providing guidelines for choosing a proper spatial resolution for simulations of crop yields at regional scale. Using a process-based crop model SIMPLACE (LINTUL2) and daily weather data at 1 km resolution we simulated a continuous rainfed winter wheat cropping system at the national scale of Germany. Then we aggregated the weather data to four resolutions from 10 to 100 km, repeated the simulation, compared them with the 1 km results, and correlated the difference with the intra-pixel heterogeneity quantified by an ensemble of four semivariogram models. Aggregation of weather data had small effects over regions with a flat terrain located in northern Germany, but large effects over southern regions with a complex topography. The spatial distribution of yield bias at different spatial resolutions was consistent with the intra-pixel spatial heterogeneity of the terrain and a log-log linear relationship between them was established. By using this relationship we demonstrated the way to optimize the model resolution to minimize both the number of simulation runs and the expected loss of spatial detail in variability due to aggregation effects. We concluded that a high spatial resolution is desired for regions with high spatial environmental heterogeneity, and vice versa. This calls for the development of multi-scale approaches in regional and global crop modeling. The obtained results require substantiation for other production situations, crops, output variables and for different crop models. (C) 2014 Elsevier B.V. All rights reserved.  
  Address  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0168-1923 ISBN Medium Article  
  Area Expedition Conference  
  Notes (up) CropM, ft_macsur Approved no  
  Call Number MA @ admin @ Serial 4753  
Permanent link to this record
Select All    Deselect All
 |   | 
Details
   print

Save Citations:
Export Records: