247 research outputs found
Predicting agronomic performance of barley using canopy reflectance data
No full textThe ability to accurately and rapidly predetermine agronomic performance would be desirable in most plant breeding programs. Remote sensing of canopy reflectance is a quick and nondestructive method that may be useful in the estimation of agronomic performance. Studies were conducted at Fargo and Langdon, North Dakota, to determine the effectiveness of a multispectral radiometer in estimating yield, kernel plumpness (KP), and 1000-kernel weight (TKW) in barley. Canopy reflectance was measured in eight (500–850 nm) discrete narrow-wavelength bands. Three types of reflectance models were evaluated: simple models using one to four wavelengths, simple ratio and normalized difference vegetation indices (NDVI) using green, red, and near-infrared wavelengths, and soil-adjusted vegetation indices (SAVI). The relationship between canopy reflectance and agronomic performance was significantly influenced by environment, growth stage, and plant genotype. Grain yield was best estimated near GS73 (0.84 < R2 < 0.92) at Fargo and at GS83 (0.55 < R2 < 0.81) at Langdon. In contrast, KP and TKW could be estimated at both late (GS83; 0.68 < R2 < 0.93) and early (GS24–GS47; 0.72 < R2 < 0.91) growth stages. The 550-nm and 800-nm wavelengths are critical for development of predictive models. A simple model using 550-nm, 600-nm, and 800-nm from GS47-GS73 gave significant (0.45 < R2 < 0.64) estimation of agronomic performance across all environments. In contrast, simple ratio, NDVI, and SAVI were less effective (0.05 < R2 < 0.77) in predicting agronomic performance. Remote sensing using canopy reflectance is a potential tool to estimate agronomic performance of barley, but genotypic and crop stage factors affect this method. Further studies are needed to improve the usefulness of multispectral radiometry in predicting agronomic performance.Steffenson, Brian; Fetch, T.G.; Pederson, V.D.. (2004). Predicting agronomic performance of barley using canopy reflectance data. Retrieved from the University Digital Conservancy, 10.4141/P02-195
Identification of Cochliobolus sativus isolates expressing differential virulence on two-rowed barley genotypes from North Dakota
No full textCanadian Journal of Plant Pathology website: http://www.tandfonline.com/loi/tcjp20Severe spot blotch infection was observed in 1990 on several two-row barley breeding lines previously regarded as resistant to
Cochliobolus sativus. Studies were conducted to compare the virulence pattern of a C. sativus isolate (ND90Pr) obtained from
this two-row breeding nursery with one (ND85F) used in previous disease screening evaluations. Greenhouse and field experiments
were performed in 1991 and 1992 at Fargo, ND, using a split plot design with isolate as the main effect. Isolates ND90Pr
and ND85F exhibited distinct differential virulence patterns on barley genotypes ND 5883, ND 12437, ND 12720, ND 12721,
and Bowman. Isolate ND90Pr displayed high virulence on ND 12720, ND 12721, and Bowman, and low virulence on ND 5883
and ND 12437. In contrast, isolate ND85F was highly virulent on ND 5883 and ND 12437 and weakly virulent on ND 12720,
ND 12721, and Bowman. Both isolates expressed low virulence on genotype ND Bl 12, the primary source of resistance to C.
sativus in commercial six-row barley germplasm. To incorporate adequate levels of resistance into future two-row barley cultivars,
disease evaluations should be made with C. sativus isolates that express the full spectrum of virulence found in North
Dakota.Fetch Jr, T.G.; Steffenson, Brian. (2009). Identification of Cochliobolus sativus isolates expressing differential virulence on two-rowed barley genotypes from North Dakota. Retrieved from the University Digital Conservancy, 10.1080/07060669409500754
The Didactic Impact of the ETN FETCH Project
No full textThe ETN FETCH project is about Future Education and Training. One of the goals was to develop new didactic models and to include social media in the process of teaching and learning. Some new didactic models have been developed. We will report about them in this paper. FETCH partners also performed some experiments using innovative teaching models as Flip the classroom and MOOCs. The results are reported at e-Learning conferences. In this paper we will discuss the to be expected impact of the innovative didactic research of the FETCH project in future Lifelong Learning. We describe some real life events underlying the same didactical principles, showing the societal relevance and impact of our developed modelsInteractive Intelligenc
Physiologic specialization of<i>Puccinia graminis</i>on wheat, barley, and oat in Canada in 2000
No full text
Effect of temperature on the expression of seedling resistance to<i>Puccinia graminis</i>f. sp.<i>avenae</i>in oat
No full textThe fetch of Mardy Watt
No full textEnigmatic chiller from the author of Calypso Dreaming. Whatever spell had been put on her was growing stronger. And suddenly, rather than fear, she felt a rush of burning anger. How dare anyone do this to her! How dare anyone steal her life! Something is haunting Mardy Watt. It's been in her room, it's fooling her friends and it's upsetting her home life. And the trouble is, nobody realises what is happening except Mardy herself. Exactly why the Fetch is picking on her, Mardy doesn't know - but she does know that she has to find out, before it takes over and replaces her completely
Fetch-limited wave growth in Nootka Sound
No full textSenior thesis written for Oceanography 445[author abstract] Ocean waves are generated at every coast line in the world. Wave generation and growth depends on wind. One hypothesis explored by this study is fetch-limited wave growth. Fetch is how far wind travels over a body of water, and the hypothesis states that the farther wind travels, the bigger waves will be. Big waves have potential for destruction, which has led many scientists to create models in an attempt to predict where, when and how big waves will be. The other goal of this study was to test the accuracy of a well-known wave predicting model used by coastal engineers. Data was gathered in a fjord called Nootka Sound using microSWIFT buoys to measure and analyze wave spectrum. The data was analyzed and fit to the Coastal Engineering Manual’s (CEM) model for wave growth. The results supported the hypothesis as larger fetch produced bigger waves. Comparing the observational data with the wave model suggested that the model was accurate for the wind conditions we were in, despite some disagreement.University of Washington School of Oceanograph
Maritime Site Protection and the Fetch Method: an example from Rogaland, Norway
No full textThis is an author accepted manuscript of the article which was published in the International Journal of Nautical Archaeology, http://onlinelibrary.wiley.com/doi/10.1111/j.1095-9270.2012.00365.x/epdf.Predictions of future requirements for the protection of maritime archaeological sites are made using the fetch method which has been developed to evaluate the quality of landing-places and navigable channels. The very useful method may explain why archaeological sites along the coast are rare in some areas, but numerous in others. Many of them are vulnerable to destruction by the effects of climate change, especially rising sea-levels, based on the IPCC scenarios. The objective fetch method can be used worldwide to predict where new finds of sites close to sea-level can be expected, and also to predict a site's vulnerability
Wind fetch and direction effects on Langmuir turbulence in a coastal ocean
No full textAuthor Posting. © American Geophysical Union, 2022. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research: Oceans 127(5), (2022):
e2021JC018222, https://doi.org/10.1029/2021jc018222.Mixing processes in the upper ocean play a key role in transferring heat, momentum, and matter in the ocean. These mixing processes are significantly enhanced by wave-driven Langmuir turbulence (LT). Based on a paired analysis of observations and simulations, this study investigates wind fetch and direction effects on LT at a coastal site south of the island Martha’s Vineyard (MA, USA). Our results demonstrate that LT is strongly influenced by wind fetch and direction in coastal oceans, both of which contribute to controlling turbulent coastal transport processes. For northerly offshore winds, land limits the wind fetch and wave development, whereas southerly winds are associated with practically infinite fetch. Observed and simulated two-dimensional wave height spectra reveal persistent southerly swell and substantially more developed wind-driven waves from the south. For oblique offshore winds, waves develop more strongly in the alongshore direction with less limited fetch, resulting in significant wind and wave misalignments. Observations of coherent near-surface crosswind velocities indicate that LT is only present for sufficiently developed waves. The fetch-limited northerly winds inhibit wave developments and the formation of LT. In addition to limited fetch, strong wind–wave misalignments prevent LT development. Although energetic and persistent, swell waves do not substantially influence LT activity during the observation period because these relatively long swell waves are associated with small Stokes drift shear. These observational results agree well with turbulence-resolving large eddy simulations (LESs) based on the wave-averaged Navier–Stokes equation, validating the LES approach to coastal LT in the complex wind and wave conditions.We acknowledge the support of National Science Foundation grant OCE-1634578 for funding this work. The Office of Naval Research funded the CBLAST-low experiment. This research was supported in part through the use of Information Technologies (IT) resources at the University of Delaware, specifically the high-performance computing resources.2022-10-2
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