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1.
Braz. j. biol ; 77(1): 140-149, Jan-Mar. 2017. tab, graf
Article in English | LILACS | ID: biblio-839157

ABSTRACT

Abstract The aim of this study was to compare vitroplants Catasetum x apolloi grown under natural light and artificial light and different concentrations of potassium silicate, providing data on the anatomical differentiation that aids the acclimatization process of this species. Plants from in vitro seeding were used; 5 protocorms of approximately 0.5 cm were inoculated into vials with a capacity of 500 mL containing 100 mL of alternative culture medium plus potassium silicate (0.0, 0.5; 1.0 mL L–1), pH adjusted to 5.5 ± 0.5 and gelated with 4GL–1 agar before the autoclaving process. Cultures were maintained under natural light (TNE) and artificial light (TAE) for 90 days, and micromorphometric analysis was performed for polar and equatorial diameter, density and stomatal index, blade thickness in the central rib, and secondary veins. Applications in K2SiO4 alternative medium provided the following: elongation of the hypodermis, thicker mesophyll, and more prominent midrib; elipptical guard cells; formation of epistomatal chamber; and lower stomatal density and stomatal with lower equatorial and polar diameters. The conditions that favored the acclimatization were lower light intensities and lower potassium silicate doses.


Resumo O objetivo desse trabalho foi comparar vitroplantas de Catasetum x apolloi cultivadas sob luz natural e luz artificial e diferentes concentrações de silicato de potássio, fornecendo dados sobre diferenciação anatômica que auxiliem no processo de aclimatação dessa espécie. Utilizou-se plantas provenientes da semeadura in vitro, 5 protocormos de aproximadamente 0,5 cm foram inoculados em frascos com capacidade para 500 mL contendo 100 mL de meio de cultura alternativo, acrescido de silicato de potássio (0,0; 0,5; 1,0 mL L–1), pH ajustado para 5,5 ±0,5 e gelificado com 4gL–1 de ágar antes do processo de autoclavagem. As culturas foram mantidas sob luz natural (TAA) e luz artificial (TAN) por 90 dias, e feitas análises micromorfométricas (diâmetro polar e equatorial, densidade e índice estomático, espessura do limbo na nervura central e nervuras secundárias). As aplicações de K2SiO4 em meio alternativo, propiciaram: alongamento da hipoderme; mesofilo mais espesso e nervura central mais proeminente; células guardas elípticas; formação de câmaras supraestomáticas; menor densidade estomática e estômatos com menores diâmetros equatorial e polar. As condições que podem favorecer a aclimatação são menores intensidades de luz e menores doses de silicato de potássio.


Subject(s)
Potassium/analysis , Plant Leaves/anatomy & histology , Orchidaceae/physiology , Light , Potassium/pharmacology , In Vitro Techniques , Silicates/analysis , Plant Leaves/chemistry , Acclimatization/physiology
2.
J Environ Biol ; 2008 Nov; 29(6): 945-50
Article in English | IMSEAR | ID: sea-113424

ABSTRACT

All the physico-chemical parameters such as temperature, salinity pH, dissolved oxygen and nutrients like nitrate, nitrite, inorganic phosphate and reactive silicate were studied in Pichavaram mangroves, southeast coast of India, for a period of two years (April 2000-March 2002). Air and surface water temperatures varied from 27 degrees C to 38 degrees C and from 26 degrees C to 37 degrees C. Salinity varied from 3.0 per thousand to 33.0 per thousand and the pH ranged between 7.2 and 8.2. Variation in dissolved oxygen content was from 2.4 to 5.0 ml l(-1). Concentrations of nutrients viz nitrates (9.50 to 32.12 microM), nitrites (1.07 to 5.99 microM), phosphates (0.73 to 2.36 microM) and reactive silicates (22.1 to 89.8 microM) also varied independently.


Subject(s)
Avicennia , Environmental Monitoring , Hydrogen-Ion Concentration , India , Nitrates/analysis , Nitrites/analysis , Oxygen/analysis , Phosphates/analysis , Rain , Rhizophoraceae , Seasons , Silicates/analysis , Sodium Chloride/analysis , Temperature , Water/chemistry , Wetlands
3.
J Environ Biol ; 2008 Sep; 29(5): 725-32
Article in English | IMSEAR | ID: sea-113670

ABSTRACT

The present study was carried out to determine the physicochemical characteristics of water and sediment and the textural aspects of sediments in western mangroves of Kachchh-Gujarat, west coast of India, for a period of two years during 1999-2000. Surface water and sediment temperatures varied from 17 degrees C to 37 degrees C and from 18.4 degrees C to 37 degrees C respectively. Tidal amplitude varied from 0.03 m to 3.78 m. Salinity varied from 34.0 to 44 per thousand and the pH in water and sediment ranged between 7.0 and 8.9 and 6.29 and 8.45 respectively. Variation in dissolved oxygen content was from 3.42 to 5.85 ml l(-1). Concentrations of nutrients viz. nitrate (0.23 to 7.26 microM), nitrite (0.04 to 0.87 microM), phosphate (0.13 to 3.12 microM) and reactive silicate (4.23 to 19.02 microM) also varied independently Total organic carbon varied from 0.29% to 2.56% and the total inorganic phosphorus ranged between 0.12 mg g(-1) and 1.97 mg g(-1). Total nitrogen varied from 0.02 mg g(-1) to 1.95 mg g(-1). Sediment textures ranges in terms of % of sand, clay and silt were: 0.26-19.2; 7.6-47 and 47-87.4 respectively in all the 3 stations. The nature of soil texture is characterized by the abundance of silty loam, silty clay and silty clay loam.


Subject(s)
Carbon/analysis , Ecosystem , Environmental Monitoring , Geologic Sediments/chemistry , Hydrogen-Ion Concentration , India , Nitrogen/analysis , Oxygen/metabolism , Phosphorus/analysis , Rain , Seasons , Silicates/analysis , Sodium Chloride/analysis , Soil , Temperature , Water/chemistry , Water Movements , Wetlands
4.
J Environ Biol ; 2005 Apr; 26(2): 291-7
Article in English | IMSEAR | ID: sea-113422

ABSTRACT

Seasonal distribution of physico-chemical characteristics such as rainfall, pH, salinity, temperature, light extinction coefficient, dissolved oxygen, biological oxygen demand and nutrients like total phosphorus, inorganic phosphate, nitrite, nitrate and reactive silicate has been studied at two stations of Uppanar estuary in relation to effluent discharges from SIPCOT industries. There are 44 industries discharges their effluents into Uppanar estuary, which may influence the biota. Nutrient concentrations were higher during monsoon season and low during summer season. The mean concentrations of nutrients were high at station 1 than station 2 due to discharges from industries, coconut husk retting grounds near the station 1. In the present study, the physico-chemical characteristic of Uppanar estuary carried out and variations are discussed.


Subject(s)
Agriculture , Environmental Monitoring , India , Industrial Waste , Nitrates/analysis , Nitrites/analysis , Oxygen/analysis , Phosphates/analysis , Phosphorus/analysis , Rain , Seasons , Seawater , Sewage , Silicates/analysis , Waste Disposal, Fluid , Water Pollutants, Chemical/analysis
5.
Rev. biol. trop ; 52(supl.1): 51-58, sept. 2004. graf, ilus, tab
Article in English | LILACS | ID: lil-450539

ABSTRACT

Cochlodinium polykrikoides was the species responsible for the discoloration that occurred between September 15th and 27th , 2000 in a shallow coastal lagoon located in the southern part of the Bahía de La Paz, on the west side of the Gulf of California. Blooms of C. polykrikoides were observed four days after two rainy days with a seawater temperature of 29 to 31°C. Nutrient concentration ranges during the bloom were 0.165- 0.897 µM NO2 +NO3 , 0.16-3.25 µM PO4 , and 1.0-35.36 µM SiO4 . Abundance of C. polykrikoides ranged from 360 x 103 to 7.05 x 106 /cells l-1 . Biomass expressed in terms of chlorophyll a was high, ranging from 2.7 to 56.8 mg/m3 . A typical dinoflagellate pigment profile (chlorophyll a and c, peridinin, diadinoxantin, and b -carotene) was recorded. In this study, the red tide occurred in front of several fish and shrimp-culture ponds. No PST toxins were found in the samples. However, 180 fish were found dead in the infected fish-pond; the gills were the most affected part. C. polykrikoides is a cyst-forming species that recurs in this area. New blooms were observed in November 2000 and September-November 2001 in the same area. Anthropogenic activities, such as eutrophication caused by water discharge in this shallow lagoon, and nutrient enrichment in the culture ponds, as well as effects from precipitation and wind stress, could have favored the outbreak of this dinoflagellate


Durante el desarrollo de una marea roja ocurrida del 15 al 27 de septiembre del año 2000 en la Ensenada de La Paz, B.C.S. se tomaron muestras de agua con una botella Van Dorn para determinar la temperatura, la especie causante y la cantidad de nutrientes y pigmentos fotosintéticos. Se hicieron análisis de toxinas de Cochlodinium polykrikoides, la especie responsable de esta marea roja. La mayoría de los especimenes formaron cadenas de cuatro células y raramente de dos. La abundancia fue de 360 x 103 a 7.05 x 106 /cels l-1 . Los florecimientos de C. polykrikoides ocurrieron cuatro días después de dos días lluviosos; el intervalo de temperatura fue de 29 a 31°C. La concentración de nutrientes registrada durante este fenómeno fue 0.165-0.897 µM NO2 +NO3 , 0.16-3.25 µM PO4 , y 1.0-35.36 µM SiO4 . El perfil pigmentario reveló la presencia de clorofila a y c, peridinina, diadinoxantina, y b -caroteno. La biomasa total expresada en clorofila a fue alta, oscilando entre 2.7 y 56.8 mg/m3 , mientras que la biomasa de Cochlodinium, expresada en peridinina, varió entre 0.68 y 32.03 mg/m3 . En este estudio, la marea roja se desarrolló cerca de varios estanques de cultivo de peces y camarón. En uno de ellos proliferó C. polykrikoides. Los análisis de toxinas PST fueron negativos; sin embargo, durante el incremento de las proliferaciones algunos estanques fueron alcanzados y murieron 180 peces, principalmente pargos (Lutjanus argentiventis, Pomadasys macracantus). Las branquias fueron las partes más afectadas. En condiciones desfavorables C. polykrikoides forma quistes, lo cual ha provocado su recurrente proliferación en el área, registrándose nuevas proliferaciones en noviembre del 2000 y en septiembre-noviembre del 2001. Actividades antropogénicas como la eutroficación causada por la descarga de aguas residuales y de nutrientes de los estanques de cultivo, pudieran estar favoreciendo la proliferación de este dinoflagelado


Subject(s)
Animals , Carotenoids/analysis , Chlorophyll/analysis , Dinoflagellida/growth & development , Ecosystem , Eutrophication/physiology , Seawater/chemistry , Anions/analysis , Antioxidants/analysis , Biomass , Cell Proliferation , Environmental Monitoring , Fisheries/statistics & numerical data , Mexico , Marine Toxins/toxicity , Population Dynamics , Phytoplankton/physiology , Silicates/analysis , Temperature , Time Factors
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