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Giant salvinia ( Mitchell; Salviniaceae) is an invasive aquatic fern that inflicts significant economic and ecological threats when unmanaged. Biological control of giant salvinia using the semi-aquatic weevil, Calder and Sands (Coleoptera: Curculionidae), has proven successful in tropical and subtropical regions. The study aimed to assess the impact of salinity on growth and health, as well as feeding behavior and density. Laboratory and outdoor mesocosm experiments were conducted at three salinity levels, <1, 5, and 10 ppt, alongside a field survey in southwestern Louisiana. Results indicated that growth and health declined with increasing salinity, with significant damage observed at 5 ppt and near-total mortality at 10 ppt. feeding showed no significant differences across salinity levels in controlled settings, but field data revealed a decrease in weevil density at higher salinities. These findings suggest that while can tolerate moderate salinity, its biological control via is less effective in saline environments. The study underscores the need for adaptive management strategies in coastal regions facing rising salinity due to climate change and sea-level rise.

A simple centroid mixture design (SCMD) method was used to determine the effect of the salinity and hardness of preparation water on final viscosity of a polymer solution with Acrylamide-Tert-butyl-Sulfonated units (ATBS). The experimental results of SCMD were used to build a special quadratic model and a numerical model was implemented for determining the polymer concentration necessary to reach the desired viscosity, depending on the salinity and hardness of the preparation water. Furthermore, the numerical model developed was validated with experimental data from the literature. It can predict the required concentration of a modified polymer (ATBS) to achieve the desired injection viscosity of the polymeric solution, with 95% reliability in the ranges evaluated. The Newton-Raphson numerical model developed using an SMCD is the first reported in the literature that allows determining the ATBS polymer concentration necessary to define the viscosity range. Un diseño de experimentos de mezcla (SCMD) fue usado para determinar el efecto de la dureza y salinidad del agua de preparación en la viscosidad final de una solución polimérica con modificaciones con unidades ATBS (Acrilamidas-Terbutil Sulfonadas). Con los resultados experimentales del SCMD se construyó un modelo cuadrático especial, y se implementó un modelo numérico que permite determinar la concentración de polímero necesaria para alcanzar la viscosidad deseada, dependiendo de la salinidad y dureza del agua de preparación. Adicionalmente, el modelo numérico desarrollado fue validado con datos experimentales de la literatura. Este puede predecir la concentración requerida de un polímero modificado con ATBS para alcanzar la viscosidad deseada con un 95% de confiabilidad en los rangos evaluados. El modelo numérico de Newton-Raphson desarrollado usando un SCMD es el primero reportado en la literatura que permite determinar la concentración de polímeros ATBS necesaria para conocer un rango de viscosidad.

Sweet sorghum (Sorghum bicolor [L.] Moench) is a plant that can be an alternative for the production of bioethanol in semi-arid regions. The objective of this work was to evaluate sweet sorghum 'BRS 506' under salt and water stress. The experimental design was in randomized blocks, in a factorial scheme (4x4), with the first factor referring to the electrical conductivities of the irrigation water (1.5; 3.0; 4.5; and 6.0 dS m-1) and the second refers to irrigation depths (53, 67, 85 and 95% of crop evapotranspiration). Gas exchange, leaf water status, leaf sugars and plant growth were evaluated. Salt and water stress cause negative effects on the growth of sweet sorghum 'BRS 506'. Salt stress causes disturbances in gas exchange and sugar levels. Sweet sorghum 'BRS 506' is tolerant to combined salt and water stress.

Identifying naturally existing abiotic-stress tolerant accessions in cereal crops is central to understanding plant responses toward sstress. Salinity is an abiotic stressor that limits crop yields. Salt stress triggers major physiological changes in plants, but individual plants may perform differently under salt stress. In the present study, 112 barley accessions were grown under controlled salt stress conditions (1 Sm-1 salinity) until harvest. The accessions were then analyzed for set of agronomic and physiological traits. Under salt stress, less than 5 % of the assessed accessions (CIHO6969, PI63926, PI295960, and PI531867) displayed early flowering. Only two (< 2 %) of the accessions (PI327671 and PI383011) attained higher fresh and dry weight, and a better yield under salt stress. Higher K+/Na+ ratios were maintained by four accessions PI531999, PI356780, PI452343, and PI532041. These top-performing accessions constitute naturally existing variants within barley’s gene pool that will be instrumental to deepen our understanding of abiotic-stress tolerance in crops.

Intense farming and irrigation practices are important causes of salinity which limit plant growth and productivity. Salinity has now impacted 6% of the total and 33% of the irrigated land. The severest salinity problem has arisen in semiarid or arid lands when they were subjected to excessive irrigation which turned hundreds of hectares of cultivated fertile lands into saline lands. When a change in salinity around the environment of a plant exceeds to a certain threshold level, the morphology and physiology of the plants are affected. This book emphasizes the menace of salinity in agriculture and crop production. It encompasses various studies on plants sensitive to salt (glycophytes) and tolerant to salt (halophytes). This book includes diversity of glycophytes and halophytes, effects of salinity on different stages of growth and development, ion homeostasis and cellular ion transport, their photosynthetic responses, effects on biological nitrogen fixation, redox regulation and phytohormonal adjustment, and significance of mineral nutrients in combating salinity in food crops. The most significant feature of the present book is its extensive coverage of genomics, metabolomics, ionomics, proteomics and transcriptomics approach, which provides a better understanding towards salt and its interaction with plants. This book is beneficial for students of stress physiology, environmental sciences, agronomy, life sciences and crop sciences at the university level.

Para la industria petrolera es importante entender el origen, migración, acumulación y alteración de los hidrocarburos presentes en la Cuenca del Valle Superior del Magdalena (VSM) y potencializar las reservas existentes y el fortalecimiento de los proyectos de exploración. Se identificaron las variables fisicoquímicas de las inclusiones fluidas analizadas, determinando la temperatura de homogenización, temperatura melting y salinidad del fluido en el momento de su entrampamiento, las cuales aportan evidencias evolutivas de la cuenca sedimentaria. De acuerdo con los resultados obtenidos se determinaron salinidades entre 22.74% a 25.51% eq. wt NaCl, calculadas gracias a las temperaturas melting que fluctúan entre -24.5°C y -20.3°C y las temperaturas de homogenización entre 130.2°C - 150°C, las cuales indican que, en el momento de entrampamiento, las rocas se encontraban en la ventana de generación de gases húmedos e hidrocarburos medianos - livianos de gran importancia para la transición energética del país.

Biodiesel is a renewable and environmental friendly energy source that can be produced via tranesterification from various oil crops such as soy bean, sunflower, palm, and algae. In this work, the microalgae Scenedesmus obliquus, S. armatus and S. bernadii, isolated from natural water basins, were enriched in modified Chu 13 medium. Only S. obliquus showed significant oil accumulation and was thus further cultivated in 3 L tubular photo-reactors under mixotrophic conditions (16:8 h light-dark cycle) at room temperature and varying CO₂ (5, 10, and 15%) supply. The results indicated that S. obliquus can be grown under various CO₂ concentrations. A maximum biomass of 2.3 g/L was achieved when 15% CO₂ was used. The effect of salinity on oil storage was also considered, using sodium chloride (NaCl) solutions of varying concentrations (0.05, 0.2, and 0.3 M). Higher lipid contents were found in cells that were subjected to salt stress compared to those in conditions without salt stress. A maximum oil accumulation of 36% was observed within 15 days at 0.3 M NaCl. A biodiesel yield of up to 97.4% was obtained.

In this study, the effects were investigated of salinity, foliar and soil applications of humic substances on the growth and mineral nutrients uptake of Corn (Hagein, Fardy10), and the comparison was carried out of the soil and foliar applications of humic acid treatments at different NaCl levels. Soil organic contents are one of the most important parts that they directly affect the soil fertility and textures with their complex and heterogenous structures although they occupy a minor percentage of the soil weight. Humic acids are an important soil component that can improve nutrient availability and impact on other important chemical, biological, and physical properties of soils. The effects of foliar and soil applications of humic substances on the plant growth and some nutrient elements uptake of Corn (Hagein, Fardy10) grown at various salt concentrations were examined. Sodium chloride was added to the soil to obtain 20 and 60mM saline conditions. Solid humus was applied to the soil one month before planting and liquid humic acids were sprayed on the leaves twice on 20th and 40th day after seedling emergence. The application doses of solid humus were 0, 2 and 4 g/kg and those of liquid humic acids were 0, 0.1 and 0.2%. Salinity negatively affected the growth of corn; it also decreased the dry weight and the uptake of nutrient elements except for Na and Mn. Soil application of humus increased the N uptake of corn while foliar application of humic acids increased the uptake of P, K, Mg,Na,Cu and Zn. Although the effect of interaction between salt and soil humus application was found statistically significant, the interaction effect between salt and foliar humic acids treatment was not found significant. Under salt stress, the first doses of both soil and foliar application of humic substances increased the uptake of nutrients.

The experiment was conducted in 2014, in a completely randomized factorial design (5x6), with three replications. The factors were soil classes (Typic Ustipsamments, Typic Haplustults, Typic Haplustepts, Typic Ustifluvents, and Typic Haplusterts) and levels of irrigation water salinity (0.5, 1.0, 2.0, 3.0, 4.0, and 5.0 dS m-1). Increasing salinity of irrigation water caused increase in leaf contents of macronutrients in all soils. Adequate leaf contents of N, K, and Mg were observed in plants grown in all soils except K in Typic Haplusterts and Mg in Typic Ustipsamments. Appropriate P levels were observed only in Typic Haplustepts, and Ca only in Typic Haplustults and Typic Ustifluvents. Increased salinity of irrigation water caused increased leaf contents of micronutrients in all soils except copper in Typic Ustifluvents, iron in Typic Haplusterts and Typic Haplustults, and manganese in Typic Ustipsamments and Typic Haplustults.

RESUMENDurante los últimos años, hasta finales de 2023, se experimentó una extraordinaria disminución en los caudales del Río Paraná y por ende en el Río de la Plata. Este fenómeno se destacó tanto por su intensidad como por su prolongada duración, adquiriendo características históricas. El presente estudio se desarrolló en el contexto de este episodio, con el objetivo de evaluar si el descenso de caudal pudiera provocar un avance del frente salino hacia el interior del Río de la Plata y eventualmente afectar la captación de las plantas potabilizadoras de la costa argentina. Para abordar esta cuestión se empleó modelación matemática, considerando diversos escenarios hidrometeorológicos y condiciones de borde. Los resultados obtenidos indican que, incluso en estas condiciones adversas, la calidad de las tomas de agua cruda no se vería comprometida por incrementos en la salinidad. Esta conclusión se respalda, al menos parcialmente, mediante mediciones de conductividad eléctrica realizadas en puntos del Río de la Plata cercanos a las tomas.