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Full-Text Articles in Life Sciences

Remote Sensing To Detect The Movement Of Wheat Curl Mites Through The Spatial Spread Of Virus Symptoms, And Identification Of Thrips As Predators Of Wheat Curl Mites, Abby R. Stilwell Dec 2009

Remote Sensing To Detect The Movement Of Wheat Curl Mites Through The Spatial Spread Of Virus Symptoms, And Identification Of Thrips As Predators Of Wheat Curl Mites, Abby R. Stilwell

Department of Entomology: Dissertations, Theses, and Student Research

The wheat curl mite (WCM), Aceria tosichella Keifer, transmits three viruses to winter wheat: wheat streak mosaic virus, High Plains virus, and Triticum mosaic virus. This virus complex causes yellowing of the foliage and stunting of plants. WCMs disperse by wind, and an increased understanding of mite movement and subsequent virus spread is necessary in determining the risk of serious virus infections in winter wheat. These risk parameters will help growers make better decisions regarding WCM management. The objectives of this study were to evaluate the capabilities of remote sensing to identify virus infected plants and to establish the potential …


Detection And Measurement Of Water Stress In Vegetation Using Visible Spectrum Reflectance, Arthur Zygielbaum Dec 2009

Detection And Measurement Of Water Stress In Vegetation Using Visible Spectrum Reflectance, Arthur Zygielbaum

Department of Geography: Dissertations, Theses, and Student Research

At any scale, from a single microbe to the planet that nurtures us, water defines our place in the universe. It provides the hydraulic forces needed to give plants structure, and the medium enabling photosynthesis, the basis for most life on Earth, to occur. Knowledge of plant water status is vital to understanding the state or condition of vegetation, information which is essential to disciplines as diverse as agriculture, geography, and climatology. Non-destructive and remote sensing of plant water status allows the gathering of such information across wide geographic extents and over long periods of time. Monitoring vegetation remotely requires …


Using The World Wide Web To Educate And Inform The Public About Risk And Agricultural Biotechnology, Douglas A. Golick, Robert D. Peterson, Leon G. Higley Jan 2009

Using The World Wide Web To Educate And Inform The Public About Risk And Agricultural Biotechnology, Douglas A. Golick, Robert D. Peterson, Leon G. Higley

Department of Entomology: Faculty Publications

The University of Nebraska and AgBios, Inc. launched the AgBiosafety website (http://agbiosaftzy.unl.edu) with the purpose of educating the public about agricultural biotechnology risk and safezy issues through science-based content. This article discusses the creation ofthe website, its components, and data gathered from usage statistics and a web-delivered survey. Also included is a discussion of the results ofdata gathered and recommendations for future web-based educational efforts in biotechnology safety and risk assessment.


Predatory Senescence In Ageing Wolves, Daniel R. Macnulty, Douglas W. Smith, John A. Vucetich, L. David Mech, Craig Packer Jan 2009

Predatory Senescence In Ageing Wolves, Daniel R. Macnulty, Douglas W. Smith, John A. Vucetich, L. David Mech, Craig Packer

USGS Northern Prairie Wildlife Research Center

It is well established that ageing handicaps the ability of prey to escape predators, yet surprisingly little is known about how ageing affects the ability of predators to catch prey. Research into long-lived predators has assumed that adults have uniform impacts on prey regardless of age. Here we use longitudinal data from repeated observations of individually-known wolves (Canis lupus) hunting elk (Cervus elaphus) in Yellowstone National Park to demonstrate that adult predatory performance declines with age and that an increasing ratio of senescent individuals in the wolf population depresses the rate of prey offtake. Because this ratio fluctuates independently of …


Long Daily Movements Of Wolves, Canis Lupus, During Pup Rearing, L. David Mech, H. Dean Cluff Jan 2009

Long Daily Movements Of Wolves, Canis Lupus, During Pup Rearing, L. David Mech, H. Dean Cluff

USGS Northern Prairie Wildlife Research Center

Wolves, Canis lupus, on Ellesmere Island traveled a daily round-trip distance of 40.2 km from their den to a landfill during July 2008, plus an undetermined distance hunting after leaving the landfill. Although long travels by Wolves are well known, this appears to be the first documentation of long daily movements by Wolves rearing pups.


Problems With The Claim Of Ecotype And Taxon Status Of The Wolf In The Great Lakes Region, Matthew A. Cronin, L. David Mech Jan 2009

Problems With The Claim Of Ecotype And Taxon Status Of The Wolf In The Great Lakes Region, Matthew A. Cronin, L. David Mech

USGS Northern Prairie Wildlife Research Center

Koblmuller et al. (2009) analyzed molecular genetic data of the wolf in the Great Lakes (GL) region of the USA and concluded that the animal was a unique ecotype of grey wolf and that genetic data supported the population as a discrete wolf taxon. However, some of the literature that the researchers used to support their position actually did not, and additional confusion arises from indefinite use of terminology. Herein, we discuss the problems with designation of a wolf population as a taxon or ecotype without proper definition and assessment of criteria.

Koblmuller et al. (2009) wrote ‘The GL …


Atlas Of Sorghum (Sorghum Bicolor (L.) Moench): Production In Eastern And Southern Africa, Charles S. Wortmann, Martha Mamo, Christopher Mburu, Elias Letayo, Girma Abebe, Kaizzi C. Kayuki, Medson Chisi, Munyaradzi Mativavarira, Soares Xerinda, Theophile Ndacyayisenga Jan 2009

Atlas Of Sorghum (Sorghum Bicolor (L.) Moench): Production In Eastern And Southern Africa, Charles S. Wortmann, Martha Mamo, Christopher Mburu, Elias Letayo, Girma Abebe, Kaizzi C. Kayuki, Medson Chisi, Munyaradzi Mativavarira, Soares Xerinda, Theophile Ndacyayisenga

INTSORMIL Scientific Publications

Grain sorghum (Sorghum bicolor (L.) Moench) is a major crop in many parts of Africa and is noted for its versatility and diversity. It is adapted over a wide range of precipitation and temperature levels and is produced at sea level to above 2000 m altitude. In eastern and southern Africa, it is primarily a crop of resource-poor, small-scale farmers and is typically produced under adverse conditions such as low input use and marginal lands. There are numerous biotic and abiotic constraints to production. The grain and stover are used in many different ways with localized preferences. Much information …


Wolf, Canis Lupus, Visits To White-Tailed Deer, Odocoileus Virginianus, Summer Ranges: Optimal Foraging?, Dominic J. Demma, L. David Mech Jan 2009

Wolf, Canis Lupus, Visits To White-Tailed Deer, Odocoileus Virginianus, Summer Ranges: Optimal Foraging?, Dominic J. Demma, L. David Mech

USGS Northern Prairie Wildlife Research Center

We tested whether Wolf (Canis lupus) visits to individual female White-tailed Deer (Odocoileus virginianus) summer ranges during 2003 and 2004 in northeastern Minnesota were in accord with optimal-foraging theory. Using GPS collars with 10- to 30-minute location attempts on four Wolves and five female deer, plus eleven VHF-collared female deer in the Wolves’ territory, provided new insights into the frequency of Wolf visits to summer ranges of female deer. Wolves made a mean 0.055 visits/day to summer ranges of deer three years and older, significantly more than their 0.032 mean visits/day to ranges of two-year-old deer, …


Farmers And Nature Conservation: What Is Known About Attitudes, Context Factors And Actions Affecting Conservation?, Johan Ahnström, Jenny Höckert, Hanna L. Bergea, Charles A. Francis, Peter Skelton, Lars Hallgren Jan 2009

Farmers And Nature Conservation: What Is Known About Attitudes, Context Factors And Actions Affecting Conservation?, Johan Ahnström, Jenny Höckert, Hanna L. Bergea, Charles A. Francis, Peter Skelton, Lars Hallgren

Department of Agronomy and Horticulture: Faculty Publications

Farmers’ attitudes towards viability of specific conservation practices or actions strongly impact their decisions on adoption and change. This review of ‘attitude’ information reveals a wide range of perceptions about what conservation means and what the impacts of adoption will mean in economic and environmental terms. Farmers operate in a tight financial situation, and in parts of the world they are highly dependent on government subsidies, and cannot afford to risk losing that support. Use of conservation practices is most effective when these are understood in the context of the individual farm, and decisions are rooted in land and resource …


Animal Helminths In Human Archaeological Remains: A Review Of Zoonoses In The Past, Luciana Sianto, Marcia Chame, Cassius S. P. Silva, Marcelo L. C. Gonçalves, Karl Reinhard, Martín Horacio Fugassa, Adauto Araújo Jan 2009

Animal Helminths In Human Archaeological Remains: A Review Of Zoonoses In The Past, Luciana Sianto, Marcia Chame, Cassius S. P. Silva, Marcelo L. C. Gonçalves, Karl Reinhard, Martín Horacio Fugassa, Adauto Araújo

Karl Reinhard Publications

The authors present a review of records of intestinal parasitic helminths from animals in human archaeological remains, reported since the emergence of paleopathological studies. The objective was to relate paleoparasitological findings to geographic, biotic, and abiotic factors from the environment in which the prehistoric populations lived, and understand some aspects related to the process of human dispersion and biological and cultural evolution. Modification of eating habits and the incorporation of new cultural practices are analyzed from the perspective of zoonoses from prehistory to the present day, especially in Brazilian indigenous populations. Three tables identifying the helminths, their natural hosts, dates, …


A Serological Survey Of Infectious Disease In Yellowstone National Park’S Canid Community, Emily S. Almberg, L. David Mech, Douglas W. Smith, Jennifer W. Sheldon, Robert L. Crabtree Jan 2009

A Serological Survey Of Infectious Disease In Yellowstone National Park’S Canid Community, Emily S. Almberg, L. David Mech, Douglas W. Smith, Jennifer W. Sheldon, Robert L. Crabtree

USGS Northern Prairie Wildlife Research Center

Background: Gray wolves (Canis lupus) were reintroduced into Yellowstone National Park (YNP) after a .70 year absence, and as part of recovery efforts, the population has been closely monitored. In 1999 and 2005, pup survival was significantly reduced, suggestive of disease outbreaks.

Methodology/Principal Findings: We analyzed sympatric wolf, coyote (Canis latrans), and red fox (Vulpes vulpes) serologic data from YNP, spanning 1991–2007, to identify long-term patterns of pathogen exposure, identify associated risk factors, and examine evidence for disease-induced mortality among wolves for which there were survival data. We found high, constant exposure to canine …