Life Sciences Commons^™

Salinity Tolerance Of Flowering Rush, Butomus Umbellatus, Andrew Coomes

Master's Theses

Flowering rush is an invasive aquatic plant in North America that causes deleterious effects to native ecosystems. There are two cytotypes, a triploid and diploid, and multiple genotypes contained within the diploid cytotype currently established in the U.S. Despite its presence in river drainages connected to estuarine areas, documentation on the salinity tolerance of flowering rush is scarce. Currently, information is limited to anecdotal reports suggesting intolerance to saline conditions. A better understanding of the osmotic tolerance of this species is essential to providing insight into its’ invasive range and better inform management efforts. These studies investigated vegetative propagule germination …

Genome-Wide Analysis Of Acute Low Salinity Tolerance In The Eastern Oyster Crassostrea Virginica And Potential Of Genomic Selection For Trait Improvement, Alexandra J. Mccarty, Standish K. Allen Jr., Louis V. Plough

VIMS Articles

As the global demand for seafood increases, research into the genetic basis of traits that can increase aquaculture production is critical. The eastern oyster (Crassostrea virginica) is an important aquaculture species along the Atlantic and Gulf Coasts of the United States, but increases in heavy rainfall events expose oysters to acute low salinity conditions, which negatively impact production. Low salinity survival is known to be a moderately heritable trait, but the genetic architecture underlying this trait is still poorly understood. In this study, we used ddRAD sequencing to generate genome-wide single-nucleotide polymorphism (SNP) data for four F_{2 …}

Copepods As A Model System For Exploring The Impacts Of Climate Change On Marine Ectotherms, Lauren Ashlock

Graduate College Dissertations and Theses

Marine ecosystems provide essential habitat to ecologically and economically impactful species and provide humans with a wealth of ecosystem services. With climate change, marine ecosystems are increasing in mean temperature and temperature variability. Marine ectotherms are vulnerable to this change and are important sentinels of warming, as their internal physiology is dependent on the external thermal environment.

Copepods are marine ectotherms that play a critical role in trophic transfer and nutrient cycling. Importantly, copepods are relatively short-lived, allowing them to track ocean change as it happens. Together, these qualities make copepods a reliable model for understanding the impacts of global …

Invasion Ecology And Response To Fire Of The Nonnative Fern Lygodium Microphyllum In The South Florida Everglades, Nicole Sebesta

FIU Electronic Theses and Dissertations

Lygodium microphyllum (Old World Climbing Fern (OWCF)) is a climbing fern native to tropical and subtropical regions of Australia, Asia, and Africa. First introduced to Florida as an ornamental in the 1960s, the fern has become a serious invasive in numerous Florida habitats, severely degrading native herbaceous and woody vegetation and altering fire behavior. One area with the greatest increase in OWCF cover is the sawgrass marsh of southern Everglades National Park (ENP), where prescribed fire is used for both maintenance of sawgrass marshes and management of OWCF infestations. However, the efficacy of OWCF control using fire in this habitat …

Investigation Of Salt Tolerance Mechanisms Across A Root Developmental Gradient In Almond Rootstocks, Yuhang Shao, Yukun Cheng, Hongguang Pang, Mingqin Chang, Fang He, Minmin Wang, Destiny J. Davis, Shuxiao Zhang, Oliver Betz, Chuck Fleck, Tingbo Dai, Shahab Madahhosseini, Thomas E. Wilkop, Judy Jernstedt, Georgia Drakakaki

Physiology Faculty Publications

The intensive use of groundwater in agriculture under the current climate conditions leads to acceleration of soil salinization. Given that almond is a salt-sensitive crop, selection of salt-tolerant rootstocks can help maintain productivity under salinity stress. Selection for tolerant rootstocks at an early growth stage can reduce the investment of time and resources. However, salinity-sensitive markers and salinity tolerance mechanisms of almond species to assist this selection process are largely unknown. We established a microscopy-based approach to investigate mechanisms of stress tolerance in and identified cellular, root anatomical, and molecular traits associated with rootstocks exhibiting salt tolerance. We characterized three …

Genetic Structure, Differentiation, And Slight Evidence For No Selective Neutrality Of Some Ssr Markers In Populations Of Medicago Ciliaris (L.) Krock And Medicago Intertexta (L.)Mill Species, Fella Abdous, Fatima Zohra Fyad-Lameche

Turkish Journal of Botany

Medicago ciliaris (L.) Krock and Medicago intertexta (L.) Mill are most often found in saline regions and are considered as potential resources for genes related to salinity resistance. To explore the genetic diversity of these two species by mean of nrSSR (simplesequence repeats) markers, 11 accessions originated from different regions in north of Africa and Middle East were chosen. Ten among 14 markers turned out to be polymorphic and gave 72 alleles. Eight markers were very informative with PIC values > 0.5, and three of them were found to be nonneutral. Allelic richness was limited with an average number of alleles …

Salinity Tolerance Of Forage Range Legumes During Germination And Early Seedling Growth, D. Sevanayak, A. Edna, R. V. Koti, M. B. Doddamani, D. Deb

IGC Proceedings (1997-2023)

Salinity is one of the rising problems causing tremendous yield losses in many regions of the world especially in arid and semiarid regions. In India, about 5.95M ha areas were affected by salinity. Five states viz. Haryana, Punjab, Rajasthan, Gujarat and Andhra Pradesh accounts for 48% of the total salt affected soils of the country. Establishment of seedlings at early growth stages of crop plants as one of the most important determinants of high yield is severely affected by soil salinity. Increasing salinity levels significantly decreased germination parameters, shoot and root length, shoot and root fresh and dry weights …

Investigating The Behavioral Response Of Lampsilis Ovata To Various Salinity Conditions, Victoria Good

Undergraduate Honors Theses

The Pocket-book mussel, Lampsilis ovata, is a native freshwater bivalve species that is endemic to North America. The salinity tolerance of this species is of interest because anthropogenic salinization events and climate change factors threaten their natural freshwater habitats. Furthermore, the invasive freshwater bivalve species Corbicula fluminea has been shown to display significant salinity tolerance, which may lead to negative competitive interactions with native freshwater bivalve species if the salinization of freshwater habitats exceeds thresholds beyond which native species can effectively cope. It was hypothesized that L. ovata would be sensitive to salinity conditions above 1 g/L and respond …

Maturation Spawning And Larviculture Of Atlantic Croaker (Micropogonias Undulatus) At Low Salinity, Edithrose Fairweather

Master's Theses

Atlantic Croaker is a popular baitfish among anglers targeting a variety of gamefish in the Gulf of Mexico. Aquaculture of this species could help meet the demand for Croaker, especially during winter when wild-caught Croaker are unavailable. Currently, Croaker aquaculture involves broodstock maturation, spawning, and larval culture at high salinity. This protocol prevents the direct use of coastal water for culture along the Mississippi Gulf coast where salinity is low. This study examined the feasibility of performing hatchery production of Atlantic Croaker at low salinity.

Culture of Croaker broodstock at 10, 20, and 30 psu during the maturation period was …

Adaptive Tolerance To Sodium Chloride In Daphnia Magna, Brady P. Parlato, Rick Kopp

Kentucky Journal of Undergraduate Scholarship

Salinity levels of some freshwater systems have been altered by humans, posing a threat to aquatic life. We hypothesized that a Daphnia magna population pre-treated with a low concentration of NaCl would develop greater salinity tolerance than an untreated population. Two Daphnia magna cultures with 60 individuals each were established, one started with 1.00 ppt NaCl and increased by 0.20 ppt weekly, and the other with pure spring water. After 4 weeks, 40 neonates from each culture were individually placed in a solution of 2.30 ppt NaCl (separately determined to be the LC₅₀) for 48 hours. Survival was …

Messina (Melilotus Siculus)–A New Pasture Legume For Saltland, Amanda L. Bonython, Andrew D. Craig, Ross A. Ballard, Nigel Charman, Philip G. H. Nichols, Clinton Revell, Natasha L. Teakle

IGC Proceedings (1997-2023)

Messina (Melilotus siculus ((Turra) Vitman ex B.D. Jacks)) is a new annual pasture legume for saltland in temperate Australia and regions of the world that experience Mediterranean climates. Messina has greater tolerance to the combined stresses of salinity and water-logging than existing commercial pasture legumes. Coupled with desirable agronomic traits these characteristics give messina the capacity to rehabilitate saltland and increase productivity on land where existing legumes fail. This paper reviews the agronomic perform-ance of messina in relation to top soil salinity levels.

Salinity Tolerance Of Gambusia Affinis, Sarah Rubelowsky

Honors Theses

Developmental plasticity refers to changes during development as a result of environmental contributions. Salinity is a varying environmental condition in freshwater and estuarine habitats that can mediate developmental plasticity in Gambusia affinis, which can increase their tolerances as an invasive species. For my study, estuarine and freshwater populations of Gambusia affinis were sampled in March of 2017 using dip nets. Both populations were then brought back to the laboratory where pregnant females were acclimated to three different salinities (0‰, 15‰, 25‰) until they gave birth. I predicted that the estuarine population of Gambusia affinis would have a greater salinity tolerance …

Molecular Genetics Of Salinity Tolerance In Rice (Oryza Sativa L.), Teresa Bermejo De Leon

LSU Doctoral Dissertations

Due to the threat of salinity stress to Louisiana rice production, an effort was made to understand the molecular genetics of salinity tolerance with the overall goal of developing salt tolerant varieties. The objectives of this study were to 1) determine if salinity tolerance exist in the US rice varieties, 2) map the additive and epistatic QTLs for traits related to seedling salinity tolerance in recombinant inbred lines (RILs) using genotyping-by-sequencing (GBS)-derived SNP markers, and 3) identify and validate stable QTLs and their effects in introgression lines (ILs) of Pokkali in Bengal background. All experiments for phenotypic characterization were conducted …

Leaf Gas Films Delay Salt Entry And Enhance Underwater Photosynthesis And Internal Aeration Of Melilotus Siculus Submerged In Saline Water, Natasha Lea Teakle, Timothy David Colmer, Ole Pedersen

Research outputs 2014 to 2021

A combination of flooding and salinity is detrimental to most plants. We studied tolerance of complete submergence in saline water for Melilotus siculus, an annual legume with superhydrophobic leaf surfaces that retain gas films when under water. M.siculus survived complete submergence of 1 week at low salinity (up to 50molm-3 NaCl), but did not recover following de-submergence from 100molm-3 NaCl. The leaf gas films protected against direct salt ingress into the leaves when submerged in saline water, enabling underwater photosynthesis even after 3d of complete submergence. By contrast, leaves with the gas films experimentally removed suffered from substantial Na+ and …

Euryhalinity In An Evolutionary Context, Eric T. Schultz, Stephen D. Mccormick

EEB Articles

This chapter focuses on the evolutionary importance and taxonomic distribution of euryhalinity. Euryhalinity refers to broad halotolerance and broad halohabitat distribution. Salinity exposure experiments have demonstrated that species vary tenfold in their range of tolerable salinity levels, primarily because of differences in upper limits. Halotolerance breadth varies with the species’ evolutionary history, as represented by its ordinal classification, and with the species’ halohabitat. Freshwater and seawater species tolerate brackish water; their empirically-determined fundamental haloniche is broader than their realized haloniche, as revealed by the halohabitats they occupy. With respect to halohabitat distribution, a minority of species (<10%) are euryhaline. Habitat-euryhalinity is prevalent among basal actinopterygian fishes, is largely absent from orders arising from intermediate nodes, and reappears in the most derived taxa. There is pronounced family-level variability in the tendency to be halohabitat-euryhaline, which may have arisen during a burst of diversification following the Cretaceous-Palaeogene extinction. Low prevalence notwithstanding, euryhaline species are potent sources of evolutionary diversity. Euryhalinity is regarded as a key innovation trait whose evolution enables exploitation of new adaptive zone, triggering cladogenesis. We review phylogenetically-informed studies that demonstrate freshwater species diversifying from euryhaline ancestors through processes such as landlocking. These studies indicate that some euryhaline taxa are particularly susceptible to changes in halohabitat and subsequent diversification, and some geographic regions have been hotspots for transitions to freshwater. Comparative studies on mechanisms among multiple taxa and at multiple levels of biological integration are needed to clarify evolutionary pathways to, and from, euryhalinity.

Salinity-Induced Structural And Functional Changes In 3 Cultivars Of Alternanthera Bettzickiana (Regel) G.Nicholson, Adnan Younis, Atif Riaz, Sana Ikram, Tahira Nawaz, Mansoor Hameed, Sana Fatima, Riffat Batool, Farooq Ahmad

Turkish Journal of Agriculture and Forestry

Three cultivars of Alternanthera bettzickiana (Regel) G.Nicholson have been evaluated for their tolerance and adaptability potential to salt stress. During the experiment, 5 salt regimes were maintained: 18 (control), 50, 100, 150, and 200 mM NaCl. Salinity adversely affected all growth shoot length and leaves per plant. Root fresh and dry weight decreased with an increase in salinity levels in all 3 cultivars. A. bettzickiana 'Green' was the most tolerant among the cultivars under study, with relatively lower ion leakage through roots, larger vascular region area, and wide metaxylem vessel in roots and stems recorded. Also observed were greater phloem …

The Effect Of Salt Stress On Antioxidative Enzymes And Proline Content Of Two Turkish Tobacco Varieties, Özge Çeli̇k, Çi̇men Atak

Turkish Journal of Biology

The aim of this study was to compare the salinity tolerances of 2 oriental tobacco varieties (İzmir Özbaş and Akhisar 97). Salinity stress experiments were performed under both in vitro and in vivo conditions. Seedlings of each variety were subjected to 0, 50, 100, 150, 200, 250, 300, and 350 mM NaCl. Photosynthetic pigment levels, lipid peroxidation rate, total protein content, antioxidant enzyme activities, and proline concentrations were determined for seedlings treated with salt for 14 days. The Akhisar 97 variety was found to be more sensitive to salinity stress than the İzmir Özbaş variety. Although proline is thought to …

Plant Growth And Mineral Element Content Of Different Gourd Species And Watermelon Under Salinity Stress, Hali̇t Yeti̇şi̇r, Veli̇ Uygur

Turkish Journal of Agriculture and Forestry

The watermelon [Citrullus lanatus (Thunb.) Matsum. and Nakai] cultivar Crimson Tide and 7 different gourd genotypes [Cucurbita maxima, C. moschata, Luffa cylindrica, Benincasa hispida, Lagenaria siceraria landraces (Skp and Birecik), and L. siceraria hybrid (FRGold)] with rootstock potential for watermelon were grown under saline conditions (0, 4, 8, 12, and 16 dS m^{-1}) to investigate the responses of the gourd genotypes and watermelon to 30 days of salt stress. Plant main stem length, shoot dry weight, root dry weight, reduction in shoot dry weight, concentration of Na^+, Ca^{2+}, and K^+ in the leaves of the genotypes, and Ca^{2+}/Na^+ and K^+/Na^+ …

Applications Of X-Ray Microanalysis In Botanical Research, Diana M. R. Harvey

Scanning Electron Microscopy

The applications of x-ray microanalysis in botanical research are reviewed, and the special problems posed in the preparation and analysis of botanical specimens and in the interpretation of results discussed. There are four main areas of research employing x-ray microanalysis:

1. effects of salinity on plants: examination of ion distributions in leaves and roots of both salt-tolerant and salt-sensitive higher plants and salt-tolerant algae and fungi;

2. effects of pollutants on plants: localization of heavy metals, particularly Pb, Cd, and Al, in algae, lichens and higher plants;

3. distributions of silicon in higher plants: silica distribution in roots and shoots, …