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2014

Drought

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Full-Text Articles in Life Sciences

Carbohydrate Metabolism And The Trehalose Biosynthetic Pathway In Maize Kernels Grown In Vitro Under Sucrose Starvation Stress, Samuel W. Bledsoe Dec 2014

Carbohydrate Metabolism And The Trehalose Biosynthetic Pathway In Maize Kernels Grown In Vitro Under Sucrose Starvation Stress, Samuel W. Bledsoe

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Drought is an increasing issue that many farmers encounter especially in hot arid climates with little rainfall. High temperatures and inadequate rainfall at certain stages in crop development can have disastrous consequences to yield. In maize, drought occurring near or during the flowering stage often causes significant kernel abortion that greatly impacts potential yield. The trehalose biosynthetic pathway has recently been found to be important in plant metabolism in response to stress in higher order plants. Trehalose is currently known throughout the plant and animal kingdoms as an osmoprotectant, high energy fuel source, structural component, and involved in pathogen response. …


Effect Of Abscisic Acid On The Growth And Development Of Lettuce (Lactuca Sativa 1.) Under Varied Irrigation Regimes, Mohamed Abdulla Al Muhairi Dec 2014

Effect Of Abscisic Acid On The Growth And Development Of Lettuce (Lactuca Sativa 1.) Under Varied Irrigation Regimes, Mohamed Abdulla Al Muhairi

Theses

Economically important vegetable crop lettuce (Lactuca sativa L.) of family Asteraceae was selected for the present investigation. It is being cultivated in UAE due to its commercial importance. In lettuce cultivation, major problem is the requirement of large quantity of irrigation water. The present study was aimed to reduce the water consumption of lettuce cultivation, for that, a varied irrigation regime was used with the application of abscisic acid (ABA). The parameters studied were growth, photosynthetic pigments, biochemical constituents, antioxidant potential and antioxidant enzymes activities in lettuce plants under drought stress and its response to ABA under stress. Drought stress …


Breeding Time In A Migratory Songbird Is Predicted By Drought Severity And Group Size, Charles R. Brown, Mary Bomberger Brown Oct 2014

Breeding Time In A Migratory Songbird Is Predicted By Drought Severity And Group Size, Charles R. Brown, Mary Bomberger Brown

School of Natural Resources: Faculty Publications

Global climate change is altering the breeding phenology of many organisms, and one reported consequence of warmer average temperatures is earlier breeding times in migratory songbirds of north temperate latitudes. Less studied are the potential interactions between earlier breeding and social behavior in colonial species. We investigated how breeding time, as measured by colony initiation dates across the entire summer, in Cliff Swallows (Petrochelidon pyrrhonota) of southwestern Nebraska, USA, changed over a 30-year period and could be predicted by climatic variables, year, and colony size. Mean colony initiation date became earlier over the study, with variation best predicted …


Zooplankton Density Increases In An Irrigation Reservoir During Drought Conditions, Brett P. Olds, Brian C. Peterson, Keith D. Koupal, Casey W. Schoenebeck, Kerri M. Farnsworth-Hoback, W. Wyatt Hoback Sep 2014

Zooplankton Density Increases In An Irrigation Reservoir During Drought Conditions, Brett P. Olds, Brian C. Peterson, Keith D. Koupal, Casey W. Schoenebeck, Kerri M. Farnsworth-Hoback, W. Wyatt Hoback

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Harlan County Reservoir, located in south-central Nebraska, entered a drought in 2003, providing an opportunity to monitor the effects of drought on the zooplankton community in this irrigation reservoir. We sampled the zooplankton community at 15 standardized locations every other week from April through the third week of October from 2003-2011. Total zooplankton densities were higher (131.8 ±13.1 L-1) in drought reservoir conditions (2003-2006) than under normal conditions (66.6 ±9.0 L-1) (2007-2011). The zooplankton community was dominated by copepods throughout the study, with adult and immature (nauplii) copepods contributing 86.5% of the total zooplankton, while Daphnia …


Evidence Of Enso Mega-Drought Triggered Collapse Of Prehistory Aboriginal Society In Northwest Australia, Hamish Mcgowan, Samuel K. Marx, P Moss, Andrew Hammond Aug 2014

Evidence Of Enso Mega-Drought Triggered Collapse Of Prehistory Aboriginal Society In Northwest Australia, Hamish Mcgowan, Samuel K. Marx, P Moss, Andrew Hammond

Samuel K Marx

The Kimberley region of northwest Australia contains one of the World's largest collections of rock art characterised by two distinct art forms; the fine featured anthropomorphic figures of the Gwion Gwion or Bradshaw paintings, and broad stroke Wandjina figures. Luminescence dating of mud wasp nests overlying Gwion Gwion paintings has confirmed an age of at least 17,000 yrs B.P. with the most recent dates for these paintings from around the mid-Holocene (5000 to 7000 yrs B.P.). Radiocarbon dating indicates that the Wandjina rock art then emerged around 3800 to 4000 yrs B.P. following a hiatus of at least 1200 yrs. …


A Case Study Of Changing Cropping Diversity And Agricultural Risk In The Doulthabad Mandal Of Telangana State In India, Srikanth Kondabolu Aug 2014

A Case Study Of Changing Cropping Diversity And Agricultural Risk In The Doulthabad Mandal Of Telangana State In India, Srikanth Kondabolu

School of Natural Resources: Dissertations, Theses, and Student Research

The Doulthabad[1] Mandal is a hot semi-arid agro-ecological sub-region (Rao et al. 2006) located in Mahbubnagar District on the North Telangana Plateau in the state of Telangana. Agriculture is the main occupation in this region, which is populated mostly with small and marginal farmers. This study uses the time period from 1971 to 2004 to study the variation in cropping pattern diversity and distribution of rainfall during the monsoons and understand the implications on production risk in agriculture. Quantitative methods were used in determining the changes in rainfall while qualitative methods were used to study cropping system changes. The …


Development Of A Public Education Website: Building Bridges Over Water, Angelina Mckee Jul 2014

Development Of A Public Education Website: Building Bridges Over Water, Angelina Mckee

Agricultural Education and Communication

Website created by Angelina McKee to educate the public about water resource issues. Water is the basic unit of life, water resources are the basis for what societies and ecosystems are founded upon. Water shortages and droughts are more prevalent in our ever-changing world. It is no shock that there are discrepancies between various stockholders on either sides of the dry riverbed. This senior project resulted in the development of a website that addresses global water resources, water use in California, water conservation, and water allocation. The website informs the public on water resources and related issues and will hopefully …


Consequences Of Browsing On Quaking Aspen’S Ability To Cope With Drought, Ivy Chatwin, Dr. Sam St. Clair Apr 2014

Consequences Of Browsing On Quaking Aspen’S Ability To Cope With Drought, Ivy Chatwin, Dr. Sam St. Clair

Journal of Undergraduate Research

Quaking aspen, Populus tremuloides, is a keystone species in forest ecosystems and is the most widely distributed tree in North America (St. Clair, Guyon, and Donaldson, 2010). Although it covers less than 10% of the forested landscape, aspen contributes disproportionately to water yield and plant and animal diversity (Kaye, Binkley, and Stohlgren, 2005). Severe drought and increased temperature in recent decades have contributed to largescale aspen die‐offs, (Worrall et al. 2007, Anderegg et al. 2012) likely through a process called hydraulic failure. Hydraulic failure occurs under drought conditions when the pressure required to draw water up a tree’s vascular tissue …


Water Availability As The Driving Factor Of Growth And Physiological Function Of Co-Occurring Scrub Species In Central Florida, Tammy Foster Mar 2014

Water Availability As The Driving Factor Of Growth And Physiological Function Of Co-Occurring Scrub Species In Central Florida, Tammy Foster

USF Tampa Graduate Theses and Dissertations

Florida scrub is a xeromorphic upland shrub community dominated by evergreen oaks that resprout after fire, occurring on moderately to excessively well-drained nutrient-poor sand. Scrub is home to several threatened and endangered animal species (e.g., Florida scrub-jay, gopher tortoise, and indigo snake) and rare and endemic plants. Urban development and agriculture has greatly reduced and fragmented scrub habitat, and because of this Florida scrub is considered one of the most endangered ecosystems in the United States. Climate change is a further threat to Florida scrub. Under a warmer and drier climate, scrub species will be exposed to more frequent and …


A Feasibility Study On Possible Uses For A Common Area Greenbelt In A Southern California Neighborhood, Sarah J. Doherty Mar 2014

A Feasibility Study On Possible Uses For A Common Area Greenbelt In A Southern California Neighborhood, Sarah J. Doherty

Horticulture and Crop Science

Common greenbelt areas within residential neighborhoods are capable of existing as multi-function zones. ‘The Village’ in Southern Orange County, California, envisions its greenbelts as benefiting the homeowners, both in cost and esthetics, all beneficial insect and plant species, and the surrounding micro-climate. Research was conducted on three different systems, aimed at improving the areas of ‘The Village’ both economically and environmentally; the areas of focus were vineyard installation, fire resistant landscaping, and low impact development installations. The process began with evaluating the sites physical and judicial restraints. Soils tests, topography calculations, climate records, and preexisting species identifications were conducted; documents …


Management Of The Great Salt Lake Ecosystem: Water, Economic Values And Competing Interests, Wayne A. Wurtsbaugh Feb 2014

Management Of The Great Salt Lake Ecosystem: Water, Economic Values And Competing Interests, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

No abstract provided.


Root Growth Of Two Perennial Grass Types And Musk Thistle (Carduus Nutans) In Temperate Grasslands Of North America, Chengchou Han, Stephen L. Young Jan 2014

Root Growth Of Two Perennial Grass Types And Musk Thistle (Carduus Nutans) In Temperate Grasslands Of North America, Chengchou Han, Stephen L. Young

West Central Research and Extension Center, North Platte

Root architecture of prairie grasslands, which depends on plant phenology and edaphic conditions, strongly influences susceptibility to invasion by nonindigenous plant species. Field studies were conducted to compare in situ root growth patterns of warm-season (WS) and cool-season (CS) perennial grasses and musk thistle during a 2-yr period that included a drought in the second year. In 2 yr, CS grasses had the highest amount of roots (1,296 m roots m–2 [395 ft roots ft–2]) across shallow (0 to 28 cm [0 to 11 in.]), medium (28 to 56 cm), and deep (56 to 98 cm) depths …


Transcriptomic Analysis Of Tomato Lines Reveals Putative Stress-Specific Biomarkers, Monther Taha Sadder, Abdullah Alsadon, Mahmoud Wahb-Allah Jan 2014

Transcriptomic Analysis Of Tomato Lines Reveals Putative Stress-Specific Biomarkers, Monther Taha Sadder, Abdullah Alsadon, Mahmoud Wahb-Allah

Turkish Journal of Agriculture and Forestry

Different abiotic stresses recruit dedicated signaling and regulatory genes in plants. Genome-wide stress-specific biomarkers were investigated in tomatoes. Three major abiotic stresses were compared: drought, heat, and salinity. For each stress type, 2 different tomato lines were included: susceptible and tolerant. Gene expression was examined by hybridizing to an available tomato microarray. Several stress responsive genes were upregulated in tolerant as well as in susceptible lines for each stress. Comparative analysis of gene expression in response to stress (drought, heat, or salinity) resolved a number of common biomarkers, while other groups of putative biomarkers were associated with each abiotic stress. …


Effects Of Extreme Hydrologic Events On Trout Populations And Fish Communities In A Catskill Mountain River, Scott Daniel George Jan 2014

Effects Of Extreme Hydrologic Events On Trout Populations And Fish Communities In A Catskill Mountain River, Scott Daniel George

Legacy Theses & Dissertations (2009 - 2024)

Extreme hydrologic events are becoming more common with changing climatic conditions. Although the impacts of winter and spring floods on lotic ecosystems have been well studied, the effects of summer floods on fish assemblages in mountain streams are less well known. This study took advantage of an extreme precipitation event during the course of an ongoing monitoring program, which allowed the opportunity to quantify the effects of a severe late summer flood on fish communities in a montane watershed. We also evaluated the effect of the flood on the density and age structure of two ecologically important populations of sport …


Characterization For Drought Resistance At Early Stages Of Wheat Genotypes Based On Survival, Coleoptile Length, And Seedling Vigor, Ali̇ Öztürk, Si̇nan Bayram, Kami̇l Hali̇loğlu, Murat Aydin, Özcan Çağlar, Sancar Bulut Jan 2014

Characterization For Drought Resistance At Early Stages Of Wheat Genotypes Based On Survival, Coleoptile Length, And Seedling Vigor, Ali̇ Öztürk, Si̇nan Bayram, Kami̇l Hali̇loğlu, Murat Aydin, Özcan Çağlar, Sancar Bulut

Turkish Journal of Agriculture and Forestry

In order to develop genotypes having a stable higher yield, it is necessary to characterize genetic resources based on drought adaptation, determine the suitable genotypes, and use them in breeding programs. This study was carried out in greenhouses, plant growth chambers, and research farms of the Faculty of Agriculture at Atatürk University. A total of 64 certified and local bread wheat genotypes were used to test survival after drought, coleoptile length, and seedling vigor. There were significant differences with respect to the selection parameters in this study. Seedling survival ranged from 18.5% to 51.1% and coleoptile lengths were 39–74 mm. …


Identification And Characterization Of A Seed-Specific Grapevine Dehydrin Involved In Abiotic Stress Response Within Tolerant Varieties, Mohsen Hanana, Samia Daldoul, Romain Fouquet, Laurent Deluc, Celine Leon, Michael Hoefer, Francois Barrieu, Abdelwahed Ghorbel Jan 2014

Identification And Characterization Of A Seed-Specific Grapevine Dehydrin Involved In Abiotic Stress Response Within Tolerant Varieties, Mohsen Hanana, Samia Daldoul, Romain Fouquet, Laurent Deluc, Celine Leon, Michael Hoefer, Francois Barrieu, Abdelwahed Ghorbel

Turkish Journal of Botany

To identify and isolate genes related to abiotic stress (salinity and drought) tolerance in grapevine, a candidate gene approach led to the isolation from Cabernet Sauvignon cultivar of a full-length cDNA of dehydrin gene. The latter, named VvDhn, which is highly and mainly induced in late embryogenesis in seeds, encodes for a protein of 124 amino acids with a predicted molecular mass of 13.3 kDa. Details of the physicochemical parameters and structural properties (molecular mass, secondary structure, conserved domains and motives, and putative posttranslational modification sites) of the encoded protein have also been elucidated. The expression study of VvDhn was …


Root Architecture Adaptation Of Pistacia Atlantica Subsp. Atlantica According To An Increasing Climatic And Edaphic Gradient: Case Of A North-South Transect In Algeria, Abdelkrim Limane, Noria Smail-Saadoun, Amel Belkebir-Boukais, Karima Kissoum-Hamdini Jan 2014

Root Architecture Adaptation Of Pistacia Atlantica Subsp. Atlantica According To An Increasing Climatic And Edaphic Gradient: Case Of A North-South Transect In Algeria, Abdelkrim Limane, Noria Smail-Saadoun, Amel Belkebir-Boukais, Karima Kissoum-Hamdini

Turkish Journal of Botany

Despite xeric conditions, Pistacia atlantica Desf. subsp. atlantica (Atlas pistachio) succeeds in developing impressive dendrometric dimensions (25-m high, 2-m trunk diameter). It is among the rare spontaneous phanerophytes of the North African steppe. With access to water being the primary condition for survival, we focused on its root system. According to a gradient of increasing climatic and edaphic aridity in Algeria, we recorded different root architectures set up by this tree. We sampled its underlying soil and determined its main physico-chemical characteristics. Root architecture is mainly of the superficial type with more than 60% of roots located in the top …


Genotypic Variability For Tuber Yield, Biomass, And Drought Tolerance In Jerusalem Artichoke Germplasm, Ruttanachira Ruttanaprasert, Poramate Banterng, Sanun Jogloy, Nimitr Vorasoot, Thawan Kesmala, Rameshwar S. Kanwar, Carl Corley Holbrook, Aran Patanothai Jan 2014

Genotypic Variability For Tuber Yield, Biomass, And Drought Tolerance In Jerusalem Artichoke Germplasm, Ruttanachira Ruttanaprasert, Poramate Banterng, Sanun Jogloy, Nimitr Vorasoot, Thawan Kesmala, Rameshwar S. Kanwar, Carl Corley Holbrook, Aran Patanothai

Turkish Journal of Agriculture and Forestry

Jerusalem artichoke could be an alternative feedstock for bioenergy during times when there are shortages of other raw materials for the ethanol industry. However, insufficient water under rainfed conditions is a major cause of Jerusalem artichoke losses. Genetic variation for drought tolerance is an essential prerequisite for the development of Jerusalem artichoke cultivars with improved drought tolerance. The objectives of this study were to determine the effects of drought stress on tuber dry weight and biomass and to investigate the genotypic variability in Jerusalem artichoke germplasm. The line-source sprinkler technique was used to compare moisture responses of a range of …


Community Structure And Differential Mortality Of Chaparral During Extreme Drought, Keb Doak, Allison Hubbard, Alawna Jamison Jan 2014

Community Structure And Differential Mortality Of Chaparral During Extreme Drought, Keb Doak, Allison Hubbard, Alawna Jamison

Featured Research

We have set out to find, in extreme drought, which species of chaparral are dominant and why they are dominating. We thought that the indicator species of chaparral, Adenostoma fasciculatum, would have highest relative density, relative frequency, and dominance in our research area. Additionally, plants with higher water potential values would have lower percentages of mortality. Chaparral with stronger ability to fluoresce (higher Fv/Fm value) would have lower mortality percentages due to their ability to dissipate excess energy, and therefore reduce water loss. By analyzing our vegetation area using point-quarter sampling system, we were able to record data that show …


Drought Effects On Composition And Yield For Corn Stover, Mixed Grasses, And Miscanthus As Bioenergy Feedstocks, Rachel Emerson, Amber Hoover, Allison Ray, Jeffrey Lacey, Marnie Cortez, Courtney Payne, Douglas L. Karlen, Stuart Birrell, David Laird, Robert Kallenbach, Josh Egenolf, Matthew Sousek, Thomas Voigt Jan 2014

Drought Effects On Composition And Yield For Corn Stover, Mixed Grasses, And Miscanthus As Bioenergy Feedstocks, Rachel Emerson, Amber Hoover, Allison Ray, Jeffrey Lacey, Marnie Cortez, Courtney Payne, Douglas L. Karlen, Stuart Birrell, David Laird, Robert Kallenbach, Josh Egenolf, Matthew Sousek, Thomas Voigt

Department of Agronomy and Horticulture: Faculty Publications

Drought conditions in 2012 were some of the most severe in recent history. The purpose of this study is to examine the impact of drought on quality, quantity, and theoretical ethanol yield (TEY) of three bioenergy feedstocks, corn stover, mixed grasses from Conservation Reserve Program lands, and Miscanthus × giganteus. To assess drought effects on these feedstocks, samples from 2010 (minimal to no drought) and 2012 (severe drought) were compared from multiple locations in the US. In all feedstocks, drought significantly increased extractives and reduced structural sugars and lignin; subsequently, TEYs were reduced 10–15%. Biomass yields were significantly reduced …