Thesis (M.S. in Physical Oceanography) Naval Postgraduate School, June 1996. / Thesis adviso(s):, Mary L. Batteen. "June 1996." "NPS-OC-96-001." Bibliography: p. 55-57. Also available online.

Thesis (Ph. D.)--University of Washington, 1995. / Vita. Includes bibliographical references (leaves [138]-144).

Thesis (Ph. D.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 84-89). Also available on the World Wide Web.

Bibliography: p. 161-185. The main aim of this project was to establish whether or not interception belts can be expected to transpire sufficient volumes of water to be considered a feasible option for controlling rising groundwater. (conclusion)

Breeding and selection for salt tolerance has been limited because of the large heterogeneity of natural saline soils and the lack of efficient criteria for measuring salt tolerance. Regulation of salt balances in leaves is an important aspect of salt tolerance. This work analyses the relationship between leaf ion concentrations and salt tolerance with the aim of using these traits as indicators of salt tolerance. This is done both in solution culture (hydroponics) and field trials (sprinkler irrigation with saline water). Varieties were found to differ in the amounts of ions accumulated in their leaves. However, these differences did not relate directly with their level of salt tolerance. The lack of correlation was partly due to difficulties in estimating salt tolerance in the field. Also, the Triple Line Sprinkler system (TLS) used in the field experiments posed several problems, the most important ones being related to direct ion absorption by the leaves. The high concentrations of CaC12 (in addition to NaCl) used in the irrigation water added a further complication. In hydroponic experiments, a minimum of 2 mol in-' Ce' was enough to prevent an indiscriminate entry of Na' and to ameliorate the growth inhibition of plants growing at 200 mol in-' NaCl. Higher Caý' concentrations (50 mol in-' CaCl2) reduced even more the concentrations of Na' in leaves without significantly affecting growth. At these high levels of CaCl2 any toxic effect was probably caused by high Clconcentrations.

Doctor of Philosophy / Department of Agronomy / P. V. Vara Prasad / Increased ambient temperature and soil salinity seriously affect the productivity of wheat (Triticum aestivum L.) which is an important cereal second to rice as the main human food crop. However, wheat plant is most susceptible to high temperatures and salinity at booting and flowering stages. Several studies have documented the effects of individual stress like salinity and high temperature stress on wheat, nonetheless little is known about effects of combined salinity and high temperature at critical growth stages. Therefore, the objectives of this research were (i) to screen winter wheat germplasm for salinity tolerance at the germination stages and to determine seedling growth traits associated with salinity tolerance, (ii) to evaluate the independent and combined effects of high temperature and salinity on winter wheat genotypes at the booting stages through growth, physiological, biochemical, and yield traits, and (iii) to evaluate the independent and combined effects of high temperature and salinity on winter wheat genotypes at the flowering stages through growth, physiological, biochemical, and yield traits. In the first experiment, 292 winter wheat genotypes (winter wheat germplasm) was screened for salinity stress at germination stage under controlled environments. The seeds were subjected to three levels of salinity, 0, 60, and 120 mM NaCl to quantify the effects of salinity on seed germination and seedling growth. In the second experiment, controlled environment study was conducted to quantity the independent and combined high temperature and salinity stress effects on growth, physiological, biochemical, and yield traits of twelve winter wheat genotypes during booting stage. Plants were grown at 20/15 °C (daytime maximum/nighttime minimum) temperature with 16 h photoperiod. At booting stages, the plants were exposed to optimum (20/15 °C) or high temperature (35/20 °C) and without (0 mM NaCl) and with (60, and 120 mM) NaCl. In the third experiment, plants were exposed to optimum or high temperature and with and without NaCl levels at flowering stages. The temperature regime and salinity levels were same as experiment II. The duration of stress was 10 d and after the stress period the plants were brought to optimum temperature and irrigated with normal water (0 mM NaCl). The results indicated that, at 120 mM NaCl, the final germination percentage was decreased and the mean daily germination was delayed. Irrespective of the genotype, salinity stress significantly decreased the shoot and root length; seedling dry matter production, and seedling vigor. Based on the seedling vigor index, the genotype GAGE, OK04507, MTS0531, TASCOSA, ENDURANCE and GUYMON, were found to be most tolerant and CO04W320, 2174-05, CARSON, OK1070275, TX02A0252 and TX04M410211 were the most susceptible to salinity at germination stage. Combined stresses of high temperature and salinity decreased photosynthetic rate and grain yields. Based on grain yield, the genotype TASCOSA was found to be most tolerant (64 % decrease) to combined stresses, and AVALANCHE was the most susceptible to combined stresses (75 % decrease) at booting stages. Similarly, at flowering stage, TX04M410211 had greater tolerance to combined stresses (65 % decline) as compared to GAGE (83 % decline). In both experiments, tolerance was associated with higher spikelet number and seed set. In conclusion, there is genetic variability among winter wheat genotypes that can be used in breeding programs to improve winter wheat yield under combined high temperature and salinity stress conditions.

A stress-induced increase in metabolic rate of fish consumes energy within the metabolic scope of a fish that could otherwise be used for such functions as growth and reproduction. By estimating the degree of the metabolic response under given salinity levels and sudden changes thereof, it could be tested whether growth under given culture conditions could be predicted. Using intermittent respirometers, this study investigated the metabolic response of juvenile Lithognathus lithognathus following gradual acclimation to 5, 25 and 35‰ and, as a result of abrupt change from 35‰ to 5‰ or from 35‰ to 25‰ at 20˚C. The main aim of the study was to establish whether the magnitude of such responses could be used to predict growth of juvenile L. lithognathus under culture conditions. Hence, in addition to the respirometry study, two growth studies were conducted at 5, 10, 25 and 35‰ salinities. The baseline metabolic rates of juvenile L. lithognathus were also determined. Oxygen consumption measurements over 24-hours showed that most fish exhibited a diurnal peak in metabolic rates. The standard and active metabolic rates calculated from juvenile L. lithognathus with a diurnal peak in oxygen consumption were 0.06±0.001mgO₂g⁻¹h⁻¹ (mean±SEM, n = 5), and 0.11±0.01mg O₂g⁻¹h⁻¹, respectively. The standard and active metabolic rates of juvenile L lithognathus showing a nocturnal peak in metabolic activities were 0.04±0.001mgO₂g-1h-1 (n = 1), and 0.12±0.003 mg O₂g⁻¹ h⁻¹, respectively. Routine metabolic rate of these fish calculated over a 3-h measurement period was 0.09±0.005mgO₂g⁻¹h⁻¹ (n = 6). Juvenile L. lithognathus showed a relationship between metabolic rate (mo₂) and body weight (W) following the equation: mo₂ = 0.62 W⁻°·⁵³.

The major aspect of this study was to evaluate the effect of changes in external salinity on the concentrations of Na⁺, C1ˉ , K⁺, Ca⁺⁺, and Mg⁺⁺ in the blood, urine, and foot muscle cells of Acmaea scutum. To estimate intracellular ion values, measurements of muscle tissue ion values and the extracellular volume (as represented by the inulin space) were made. As well, aspects of the water balance of A. scutum have been studied; the effect of changes in external salinity on water content of whole animal, and muscle cells has been documented; and the water content of animals maintained at a constant salinity has been studied. The results showed that ion values of the blood, except for K⁺, were the same as respective ion values of external salinities. At all salinities the concentration of K⁺ in the blood was greater than sea water K⁺ values. Dialysis experiments showed the gradient was not due to a Donnan equilibrium. All urine ion values were the same as ion values of external salinities. The K⁺ gradient observed between blood and sea water did not exist between urine and sea water. Extracellular volume of foot muscle changed linearly with change in external salinity (16.7% at 50% sea water and 3l.0% at 125% sea water). This change in extracellular space indicated that cellular volume changed with changes in external salinity. Intracellular ion values were different than blood ion values. Intracellular estimates of Na⁺ and C1ˉ were, at all salinities tested, close to or not significantly different from zero. Intracellular K⁺ estimates were, at all salinities, much higher than blood K⁺ values. Intracellular K⁺ values also changed significantly with changes in external salinity. Over a range of salinities from 50 to 125% sea water intracellular K⁺ values appeared to increase linearly. Intracellular values of.Ca⁺⁺ and Mg⁺⁺ were lower than corresponding values of experimental salinities. At a given salinity the sum of intracellular ion values was much lower than the sum of blood ion values. Results on seasonal distribution of ions and water of foot muscle for animals from a constant salinity showed that over an 18 month period muscle ion and water values varied significantly. As well, water content values of whole animal for the same field samples varied significantly. Water content of whole animal also changed significantly with changes in external salinity. For A. scutum from a marine environment changes in water content caused by changes in experimental salinities were maintained for up to one week immersion. Whole animal water content for A. scutum from an estuarine environment however, returned to starting water content values after 48 hr immersion in experimental salinities. Whole animal water content data for field samples from an estuarine environment indicated little volume regulation. Over a range of environmental salinities from 18% to 82% sea water, water content ranged from 89.0% to 77.0%. As well as showing changes in total body water with changes in external salinity, A. scutum demonstrated large changes in water content at a given constant salinity. Changes in water content at a constant salinity resulted from sea water entering the blood space from the external environment. When the molecules inulin and amaranth were dissolved in experimental salinities and the water uptake response tested, these molecules also entered the blood space from the external salinities. The ion values of blood, urine, and muscle cells were similar to values of these parameters recorded for other gastropod molluscs. Water content values from experiments on the effect of change in external salinity also agreed with data from studies on other molluscs. The water uptake response of A. scutum however, was not in accordance with measurements on change in blood volume at constant salinities for other gastropod molluscs. A definite example of a gastropod that can take sea water from the external environment into the blood space must now be added to the literature. / Science, Faculty of / Zoology, Department of / Graduate

Two factorial greenhouse experiments were performed to determine the effects of four arbuscular mycorrhizal fungi (AMF) species (Glomus arenarium, Funneliformis caledonius, F. mosseae, and Rhizophagus irregularis) and a root endophyte (Piriformospora indica) on four ‘day-neutral’ strawberry (Fragaria × ananassa Duch.) cultivars (‘Albion’, ‘Charlotte’, ‘Mara des Bois’, and ‘Seascape’), and mixed-AMF species (R. irregularis + F. mosseae) on cv. ‘Seascape’, under salt conditions (0-200 mM NaCl). In its biomass, ‘Seascape’ was more tolerant to salinity than the other cultivars. Cultivars responded differently to fungal inoculation as to salinity. G. arenarium had a negative effect on plant growth and ‘Mara des Bois’ responded negatively to inoculation. Among the remaining inoculants and cultivars, fungal-symbiosis was beneficial to growth. R. irregularis alleviated the symptoms of salt stress and improved fruit quality to a higher degree than the other AMF species and the root endophyte. Our results support the use of bio-inoculants in salty horticultural areas.

Most crop species are highly sensitive to elevated levels of soil salinity. Increased soil salination has become one of the most detrimental environmental factors limiting agricultural productivity. Agricultural commodity losses due to salinity are currently estimated to be 12 billion USD per year and are expected to increase every year as more acreage is affected by salination. The Elymus genus is composed of approximately 150 species of grasses with geographic distribution that spans the globe. Elymus species are commonly used for revegetation, wildlife habitat, and erosion control. While increased tolerance to soil salinity has been reported that Argentine wheatgrass (Elymus scabrifolius (Doll) J.H. Hunz.)) and sand couchgrass (Elymus farctus L.) it is currently unknown if the ability to tolerate increased soil salinity exists in four popular North American Elymus species including southeastern wildrye [Elymus glabriflorus (Vasey ex L.H. Dewey)], Canada wildrye (Elymus canadensis L.), Virginia wildrye (Elymus virginicus L.), and riverbank wildrye (Elymus riparius Wiegand). In this study, tolerance to salinity was evaluated in these four species at the seed germination and seedling stage. The germination test was performed by watering seeds with 0, 100, 200, 300, and 400mmol NaCl and placing them in a controlled environment chamber. The tolerance level was determined by germination rate. The seedling stage test was performed by irrigating seedlings with the same salinity levels in a greenhouse and monitoring injury and biomass yield reduction. This research will help identify salinity tolerance in these popular Elymus species at different life stages, allowing land managers and producers to make informed species selection decisions for revegetation, grazing, erosion control or habitat management when soil salinity is an issue.