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Copyright of Boletín de la Sociedad Argentina de Botánica is the property of Sociedad Argentina de Botanica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The characteristics of the northern coastal plain from Nayarit state, Mexico, were presented in two previous papers, as well as soil distribution in five levels of the plain: marine fluvial plain with three levels (high, medium and low), current tide flooding plain and parallel bar zone, beaches and coastal dunes. Therefore, the main soils of this region: Cambisols, Fluvisols, Feozems, Gleysols, Regosols, Arenosols and Solonchaks, besides the characteristics of the most frequent soils--Cambisols and Fluvisols- at the three plain levels were determined. This paper shows important characteristics of the soils formed in the lowest coastal plain: tide flooding plain, parallel bars, beaches and coastal dunes. Data from morphological characteristics, and physico-chemical texture of the main soils -Solonchaks, Regosols and Arenosolsare also presented. This paper comprises the geographical and edaphological characterization stage of the northern coastal plain, that will be good for further investigations starting on the use and sustainable management of agricultural production in this region, a very important aspect to Nayarit state. [ABSTRACT FROM AUTHOR]

The effect of two formulations based on spirostane brassinosteroid analogs known as BIOBRAS-6 (BB6) and BIOBRAS-16 (B16) on seedling growth of two rice varieties under saline conditions was studied in the present paper. Seeds of J-104 and INCA LP-7 varieties were dipped in water, 100 mM NaCl or 100 mM NaCl supplemented with different concentrations (1, 0.5, 0.05 and 0.005 mg.L-1) of B16 or BB6 for 24 hours. Later, seeds were placed in Petri dishes with filter paper dampened with distilled water for germination and maintained in a growth chamber at darkness during 48 hours. Germinated seeds were transferred to pots containing the different assayed solutions and placed in a growth chamber with 16 hour- photoperiod and 25±2°C temperature for seven days. At the end of the experiment, shoot and root lengths as well as fresh and dry weights were evaluated. Results showed that, in general, 0.005 mg.L-1 of B16 was the most effective treatment to revert adverse effects induced by salinity in both varieties, whereas the response to BB6 depended on the variety. [ABSTRACT FROM AUTHOR]

At present, salinity is one of the most pressing causes of stress, and brassinosteroids are compounds which stimulate plant growth and also, increase the plant tolerance to salt stress. In this paper, the effect of foliar spraying with a natural brassinosteroid (24-epibrassinolide, EBL) in rice seedlings subjected to this kind of stress was evaluated. To do this, rice young plants of J-104 and Gines cultivars were sprayed with EBL (2 μmolL-1), and then, half of them were treated with NaCl (100 mmolL-1) for seven days, and later, they were transferred to nutrient solution to assess recovery for 14 days. Evaluations of growth (length and dry mass of aerial parts and roots) were performed at three and seven days of saline treatment and seven and 14 days of recovery. Some indicators of photosynthesis such as photosynthetic rate, stomatal conductance, transpiration, intercellular CO2 concentration and photosynthetic pigments (chlorophylls and carotenes) were also determined. The results showed that, in general, foliar spraying with EBL 2 μmolL-1 stimulated the length and dry mass of rice seedlings of both cultivars under saline conditions which appear to be associated with increased photosynthesis, gas exchange and chlorophyll concentration. [ABSTRACT FROM AUTHOR]

The objective of this study is to examine the effectiveness of the removal of polymeric humic matter during coagulation-flocculation and to highlight stoichiometric relationships between the coagulant dosage and the organic substance content. It is therefore a question of assessing the influence of reaction parameters such as the dose of aluminum sulfate, the concentration of humic acid, the pH and the saline composition of the water during the coagulation-flocculation treatment. To establish correlations between the initial organic compound content and the coagulant dosage, humic acid was dissolved at levels of 1 to 20 mg/l in distilled water and mineralized groundwater from the Biskra area at different pH values. Then, solutions were coagulated by increasing doses of aluminum sulfate. The organic compound final concentrations are deduced from the calibration curves, which were previously established for the tested compound in the various dilution media. The results obtained indicate that the process efficiency as well as the coagulant dosage depend on the pH, the organic compound initial concentration and the characteristics of the dilution medium. The findings also showed that increasing water salinity had a promoting effect on humic acid removal. The predominant mechanisms of the tested organic acid removal process were complexation phenomena or ligand exchange with soluble or insoluble aluminum species. Demonstration of the stoichiometry of the reactions showed that the relationships linking the dosage of the coagulant to the initial concentration of humic acid essentially depended on the pH and the salinity of the different waters tested. [ABSTRACT FROM AUTHOR]

Copyright of Revista FAVE is the property of Universidad Nacional del Litoral and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The soil salinity affects food production worldwide. This shows a tendency to increase in coming years worldwide, as well as Cuban territory, where this environmental phenomenon, regardless of weather conditions, has led to processes of soil degradation, affecting crop yields of major interest in the national economy. Salt stress, causes physiological and biochemical changes in plant metabolism that determine their survival and productivity in these conditions, so plants have evolved mechanisms of tolerance. Genetic improvement offers an increase in both the recovery of underutilized areas, and yields in areas where salinity is a limiting factor or for which you work in various ways. Given that the selection of salt tolerant plants, is a long process determinedly, working in the search for efficient indicators for early selection of genotypes with better agronomic performance. These aspects are addressed in this paper focusing on the improvement as an effective tool for the selection of genotypes of different crops with better performance under salt stress. [ABSTRACT FROM AUTHOR]

The objective of this paper is to show an alternative for the coexistence with the salinity problem of irrigation water caused by underground dams. The quality of irrigation water is analyzed by comparing the vegetative growth of Capim Vetiver, Sempre Verde, Cana-de-Açúcar, Capim Elefante cv. Napier and Capim Elefante cv. Mercker, upstream and downstream of the underground dam located in Ibicuitinga, Ceará state in Brazil. The analysis of groundwater samples upstream and downstream of the dam have shown that both have high salinity for irrigation, recommending the use of halophytes crops. The study includes an analysis of variance for height growth variable and the Tukey test was applied. From this test it was verified that among the gramineous plants tested, only the Capim Elefante cv. Mercker was found statistically different. [ABSTRACT FROM AUTHOR]

The Province of Mendoza has the largest irrigated area in Argentina with a vast irrigation and drainage infrastructure in the oases of its main five rivers. Soils are alluvial and their profiles reveal alternate layers of different textures, and very thin -almost impervious- strata prevent free drainage of irrigation water. This dynamic situation is more evident as the river slope diminishes in the lower sectors of the basin. Water accumulation raises water table level practically up to soil surface, which increases soil salinization. The command area of the Mendoza River, with mean water salinity values of less than 1 dS.m-1 at its point of diversion to the irrigation system, is one of the most intensely exploited areas in the country and has two sectors with very high water tables (our study areas): a central area known as spring water area AS, and another area identified as the Lavalle Area AL. At AS there are 98 observation wells to determine depths, flow direction, and phreatic water quality. The AL has 100 observation wells distributed in three subareas corresponding to three drainage collectors: Tres de Mayo-Jocolí TMJ, Villa Lavalle VL, and Costa de Araujo-Gustavo André CG. This paper presents the results of a phreatic water salinity assessment, which are expressed as total salinity at 25 °C (EC) for both study areas. Samples were drawn in 2002 and 2004. Results obtained show that, at the two sampling moments, the median is smaller than the corresponding mean, which is indicative of positive asymmetry in the distributions; median values were 6180 µS cm-1 (2002) and 6195 µS cm-1 (2004). There were also changes in distribution between the sampling moments and between the areas. In 2004 extreme upper values were much higher than in 2002; and in the VL area relative frequencies were more uniform while EC increments were greater. It was also observed that the AS area had the lowest EC values at both sampling moments, although it was also the area with more outliers; that there have been no significant (α = 0.05) changes in EC in the TMJ, CG and AS areas in two years but that there has been a substantial rise in EC in VL. Refined data were used to draw isolines for various intervals of the variable under analysis (EC), and they show the sectors affected by different phreatic salinity intervals. [ABSTRACT FROM AUTHOR]

Copyright of Ingeniería Agrícola is the property of Instituto de Investigaciones de Ingenieria Agricola and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Terra Latinoamericana is the property of Sociedad Mexicana de la Ciencia del Suelo A.C. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Biológica Colombiana is the property of Universidad Nacional de Colombia, Facultad de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of BIOAGRO is the property of Revista BIOAGRO and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Boletín de la Sociedad Geológica Mexicana is the property of Sociedad Geologica Mexicana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Boletín de la Sociedad Geológica Mexicana is the property of Sociedad Geologica Mexicana and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)