26 research outputs found
Adaptación a la sequÃa y necesidades hÃdricas de Eucalyptus globulus Labill. en Huelva
Eucalyptus globulus Labill. es una especie
ampliamente utilizada en plantaciones para
producción de madera. Está adaptada a vivir sobre
suelos pobres y bajo clima mediterráneo pero suave
y con influencia oceánica. Soporta cierto grado de
estrés hÃdrico pero le van mal temperaturas extremas
que sobrepasen 40 ºC ó -5 ºC. Su cultivo en la
provincia de Huelva está seriamente limitado por la
frugalidad de los suelos y la sequÃa estival, asà como
por el ataque de plagas, especialmente virulentas en
situaciones de estrés hÃdrico como en el caso de
Phoracantha spp. En este trabajo se muestra una
recopilación de varias experiencias, llevadas a cabo
en vivero y en parcelas de campo, sobre la reacción
de los clones al estrés hÃdrico y sus necesidades de
consumo de agua. Al igual que para otros tipos de
estreses biótico o abióticos, la especie manifestó
variabilidad genética (a nivel clonal) en su grado de
resistencia al estrés hÃdrico, lo que ofrece la
posibilidad de seguir desarrollando programas de
selección y mejora de la especie destinada a
plantaciones forestales. Dicha resistencia se
implementaba al ser expuestos a situaciones de
estrés hÃdrico, poniendo en juego mecanismos de
evitación (morfologÃa foliar, cierre estomático,
vulnerabilidad a la cavitación del xilema, etc.) y de
tolerancia (ajuste osmótico y elástico). No obstante
el grado de variación de cada uno de los parámetros
medidos difirió entre los clones, manifestando
distintas estrategias entre clones, lo que puede ser
utilizado a la hora de establecer el criterio de
selección en función del objetivo perseguido en cada
lÃnea de mejora (resistencia al ataque por
Phoracantha spp., producción y eficiencia en el uso
del agua, resistencia a valores crÃticos de estrés
hÃdrico, etc.).___________________________________________Eucalyptus glubulus is a widely used species in
forest plantations for wood production. It is adapted
to live on poor soils under Mediterranean climate
with oceanic influence. It supports some degree of
water stress but not extreme temperatures exceeding
40 ºC or -5 ºC. Its cultivation in the province of
Huelva is seriously limited by the frugality of the
soils and the summer drought, and it is attacked by
pests such as Phoracantha spp., particularly virulent
under water stress conditions. In this work, we
analyzed the results of several experiments, carried
out in nurseries and in field plots, regarding to the
response of E. globulus clones to water stress and its
water consumption needs. As for other biotic or
abiotic stresses, the species showed genetic
variability (at clonal level) in their resistance to
water stress, which offers the possibility to further
develop and improve breeding programs. Under
water stress conditions, it reacts by coming into play
avoidance mechanisms (leaf morphology, stomatal
closure, vulnerability to xylem cavitation, etc..) and
tolerance mechanisms (osmotic and elastic
adjustment). However, the degree of variation of
each of the above cited parameters differed between
clones, showing different strategies among them.
This can be used when establishing the selection
criteria in relation to the purpose of each breeding
program (resistance to be attacked by Phoracantha
spp., production and water use efficiency, resistance
to threshold values of water stress, etc.
Biomass Yield and Economic, Energy and Carbon Balances of Ulmus pumila L., Robinia pseudoacacia L. and Populus × euroamericana (Dode) Guinier Short-Rotation Coppices on Degraded Lands under Mediterranean Climate
The steadily increasing demand for energy and concerns about climate change have
prompted countries to promote the use of renewable energy sources, including lignocellulosic
biomass. In this context, this work aims to assess the biomass production for energy purposes in
crops with short rotation, as well as its effect on soil properties. Deciduous tree species were used,
mainly Siberian elm (Ulmus pumila L.), black locust (Robinia pseudoacacia L.) and a hybrid poplar clone
(Populus × euroamericana (Dode) Guinier, clone ‘AF2’). Four field trials were implemented, under two
different types of Mediterranean climate, where highly productive taxa were tested, in addition to the
mixed planting of a nitrogen-fixing species with a non-fixing one. Short-rotation coppices (SRCs) of
these taxa yield about 12–14 t ha−1 year−1 of high-quality dry woody biomass, when fertilizers and
irrigation water are supplied; generate 205–237 GJ ha−1 year−1 net and earnings of about EUR 1.5 per
EUR 1 invested; and sequester into the soil 0.36–0.83 t ha−1 year−1 of C and 57 kg ha−1 year−1 of N.
Therefore, these species raised as SRCs could improve degraded soils if the crop is properly managed,
resulting in favorable economic, energy and CO2 emission balances. The use of mixed plantations
can bring economic and environmental gains, and the biomass transformation into high-quality chips
or pellets gives it added valueThis research was funded by the Science and Innovation Ministry (ref. AGL2010-16575)
and the Economy and Competitiveness Ministry of Spain (ref. CTQ2013-46804-C2-1-R and CTQ2017-
85251-C2-2-R), by FEDER funds of the EU, and by the company ENCE, energÃa y celulosa S.A. (8%, 6%,
6%, 70%, 10%, respectively).
The authors want to thank the Diputación de Granada (Spain) for the donation
of farmland for the establishment of the experimental plots in Los Morales, and for the help in the
cultivation works; the company Tubocás S.L. for its contribution to the sampling and transport of
biomass, as well as to the harvest at the end of each crop rotation; and Biopoplar Ibérica S.L. for the
provision of some plant tax
Metsulfuron-methyl determination in environmental samples by solid surface fluorescence
A new environmental friendly methodology for metsulfuron-methyl quantification based on the fluorescent signal enhancement of rhodamine B dye has been developed. A cationic surfactant (cetyltrimethylammonium bromide, CTAB) and an anionic one (sodium dodecylsulfate) were employed to preconcentrate the herbicide using a coacervation phenomenon, in sodium borate buffer medium (pH 9.2). The coacervate phase was collected on a nylon membrane (0.45 μm) and the solid surface fluorescence signal was determined (λexc = 515 nm, λem = 565 nm). Experimental variables that influence on preconcentration step and fluorimetric sensitivity have been studied and optimized using response surface methodology. Under optimal working conditions, a LOD of 0.17 μg L−1 and a LOQ 0.53 μg L−1 was obtained. The zeroth order regression calibration was linear from 0.53 to 5.00 μg L−1. The method showed adequate sensitivity and selectivity, and was applied to the determination of trace amounts of metsulfuron-methyl in environmental water samples. The proposed methodology implies an alternative to traditional techniques for metsulfuron-methyl monitoring using an accessible instrument in control laboratories, representing a contribution in the toxicological and environmental areas for the monitoring of MSM in environmental samples, in agreement with the Green Chemistry.Fil: Alesso, Magdalena. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - San Luis. Instituto de QuÃmica de San Luis. Universidad Nacional de San Luis. Facultad de QuÃmica, BioquÃmica y Farmacia. Instituto de QuÃmica de San Luis; ArgentinaFil: Almeida, César Américo. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - San Luis. Instituto de QuÃmica de San Luis. Universidad Nacional de San Luis. Facultad de QuÃmica, BioquÃmica y Farmacia. Instituto de QuÃmica de San Luis; ArgentinaFil: Talio, MarÃa Carolina. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - San Luis. Instituto de QuÃmica de San Luis. Universidad Nacional de San Luis. Facultad de QuÃmica, BioquÃmica y Farmacia. Instituto de QuÃmica de San Luis; ArgentinaFil: Fernandez, Liliana Patricia. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - San Luis. Instituto de QuÃmica de San Luis. Universidad Nacional de San Luis. Facultad de QuÃmica, BioquÃmica y Farmacia. Instituto de QuÃmica de San Luis; Argentin
Evolución temporal del grado de endurecimiento de plantas de vivero de 4 especies forestales españolas cultivadas en localidades con condiciones climáticas distintas
Desde principio del otoño hasta principio de primavera se estudió la evolución de algunos caracteres morfo-fisiológicos indicadores de la calidad de las plantas de vivero destinadas a repoblación forestal (altura, diámetro, distribución de biomasa, nutrición mineral, capacidad de regeneración de raÃces y resistencia al frÃo). Las especies ensayadas fueron Quercus suber, Q. ilex (de dos regiones de procedencia, 11e y 15a), Pistacia lentiscus y Olea europaea var. sylvestris. Todas ellas eran de una savia, procedentes de semillas germinadas en la primavera anterior, crecidas en el mismo tipo de
o
envase (300 cm3) y con el mismo substrato pero cultivadas en dos viveros de localización y caracterÃsticas climáticas diferentes. En cuanto al patrón de evolución temporal de los parámetros medidos, se advirtió una alta correlación con la temperatura ambiente, siendo el vivero de clima con estaciones más marcadas el que alcanzó con anterioridad su grado máximo de resistencia al frÃo y el que retrasó la salida de la dormición durante la época invierno-primavera. Indudablemente, las distintas especies se diferenciaron en su patrón de evolución y en el grado de resistencia al frÃo conseguido, debiendo resaltar las diferencias encontradas entre las dos procedencias de encina, siendo la de clima con estaciones más extremas (15a) la que en todo momento presentó un mayor grado de resistencia al frÃo. También se encontró un alto grado de correspondencia entre el contenido en K y la resistencia al frÃo o el contenido en N y P con la capacidad de regeneración de raÃces. Las cuatro especies necesitaron acumular, al menos, 350 h (< 8 °C) para conseguir un grado apreciable de resistencia al frÃo, alcanzándose el máximo resistencia entre 700 y 800 h
Leguminosas leñosas de rápido crecimiento como cultivos energéticos en el Suroeste de la PenÃnsula Ibérica
Este estudio pretende evaluar las posibilidades del
empleo de leguminosas leñosas de rápido
crecimiento como cultivos destinados a la
producción de biomasa como fuente de energÃa.
El ensayo consistió en el cultivo de 14 especies /
procedencias de los géneros Leucaena (L.
leucocephala, L. salvadorensis, L. diversifolia, L.
collinsi), Prosopis (P. alba y P. julyflora), Sesbania
(S. sesban), Chamaecytisus (C. proliferus var
palmensis) y Retama (R. monosperma). Las plantas
fueron producidas a partir de semillas e inoculadas
con bacterias del género Rhizobium. Tras una fase de
vivero fueron transplantadas en dos parcelas de
ensayo sometidas a dos regÃmenes de riego. Durante
el cultivo se monitorizó el crecimiento (altura,
diámetro y peso). La producción anual de biomasa
se evaluó durante 3 años consecutivos bajo tres
sistemas de aprovechamiento: cortas anuales o a los
2, y 3 años.
Todas las especies y variedades salvo Leucaena
salvadorensis y Sesbania sesban mostraron una
buena adaptación edafo-climática a las
caracterÃsticas de la zona de estudio (Huelva). La
variación en las tasas de crecimiento entre especies
fue muy grande desde las 0.3 toneladas de materia
seca leñosa por hectárea y año (Retama
monosperma, Prosopis julyflora) hasta las 25-35 t/ha
y año (Luecaena leucocephala). Todas las especies
soportaron bien las cortas anuales menos
Chamaecytisus proliferus que se mostró muy
sensible a la corta del primer año sobretodo en la
parcela más regada._____________________________________We cultivate 14 species / provenances of genera
Leucaena (L. leucocephala, L. salvadorensis, L.
diversifolia, L. collinsi), Prosopis (P. alba and P.
julyflora), Sesbania (S. sesban), Chamaecytisus (C.
proliferus var palmensis) and Retama (R.
monosperma). The plants were produced from seeds
and inoculated with specific bacteria of the genus
Rhizobium. After a nursery phase, seedling were
planted in two experimental plots subjected to two
water regimes. Annual biomass production was
evaluated under three management systems: annual
biannual and three annual clear-cutting
All the species and varieties except Leucaena
salvadorensis and Sesbania sesban showed a good
edafo-climatic adaptation to the characteristics of the
study area (Huelva). Variation in growth rates
among species was high, from the 0.3 t of woody
dry matter per hectare and year (Retama
monosperma, Prosopis juliflora) until 25-35 t ha-1
year-1 (Leucaena leucocephala). All the species
supported annual cutting with a vigorous re-sprouts
except Chamaecytisus proliferus that was very
susceptible especially in the most irrigated plots
Cyclodimerization of stilbenes and styrenes catalyzed by heteropolyacid supported on silica
Several stilbenes and styrenes have been treated with heteropolyacid] (HPA) supported over silice. The compounds obtained were characterized by 1H and 13C-NMR and the yields were compared with those obtained using H2SO4 (c) and ethyl poliphosphate (PPE).Facultad de Ciencias Exacta
Caffeine determination by flow injection analysis employing Bovine Serum Albumin as a fluorophore
A new methodology for caffeine determination was developed based on the quenching effect on fluorescent emission of the molecule of Bovine Serum Albumin at λem = 338 nm (λex = 280). A flow injection disposition was designed improving significantly the sampling rate to 60 samples/h using potassium dihydrophosphate 5 · 10-3 mol L-1 buffer (pH 6.8) as carrier and flow rate of 1.5 mL min-1. The experimental and instrumental conditions that influence on analytical quality parameters were systematically investigated, as consider: buffer nature and concentration, fluorophore nature and concentration, and carrier flow rate. The proposal is simple, fast, inexpensive and precise, with a linear range from 6.68 · 10-6 to 4.0 · 10-3 mol L-1 and SD of 0.0668, under optimized conditions. Methodology sensibility and selectivity allowed a variety of sample analyses. It was successfully applied to caffeine quantification in energy drinks, dietary supplements and sliming infusion samples without previous treatment.Fil: Alesso, Magdalena. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - San Luis. Instituto de QuÃmica de San Luis. Universidad Nacional de San Luis. Facultad de QuÃmica, BioquÃmica y Farmacia. Instituto de QuÃmica de San Luis; ArgentinaFil: Fernandez, Liliana Patricia. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - San Luis. Instituto de QuÃmica de San Luis. Universidad Nacional de San Luis. Facultad de QuÃmica, BioquÃmica y Farmacia. Instituto de QuÃmica de San Luis; Argentin
Solid surface fluorescence methodology for fast monitoring of 2,4-dichlorophenoxyacetic acid in seed samples
A new method for pre-concentration/separation and determination of 2,4-dichlorophenoxyacetic acid (2,4-D) by solid-surface fluorescence (SSF) is proposed. The herbicide was complexed with Rhodamine B at pH 7.0 in the presence of phosphate buffer and anionic surfactant admicelles. A Nylon membrane was selected as a solid support for SSF measurement and the presence of 2,4-D was evident by the RhB quenching effect. Under optimal experimental conditions, the limit of detection and quantification were 6.93 and 21 ng L−1 , respectively, and the linear range was obtained from 0.021 to 22.11 μg L−1 2,4-D concentration. The developed methodology showed good sensitivity and adequate selectivity, and it was applied to the 2,4-D determination in seed samples. The SSF represents a simple and fast alternative to conventional methods of analysis, employing an existing instrument in most laboratories.Fil: Alesso, Magdalena. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - San Luis. Instituto de QuÃmica de San Luis. Universidad Nacional de San Luis. Facultad de QuÃmica, BioquÃmica y Farmacia. Instituto de QuÃmica de San Luis; ArgentinaFil: Talio, MarÃa Carolina. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - San Luis. Instituto de QuÃmica de San Luis. Universidad Nacional de San Luis. Facultad de QuÃmica, BioquÃmica y Farmacia. Instituto de QuÃmica de San Luis; ArgentinaFil: Fernandez, Liliana Patricia. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - San Luis. Instituto de QuÃmica de San Luis. Universidad Nacional de San Luis. Facultad de QuÃmica, BioquÃmica y Farmacia. Instituto de QuÃmica de San Luis; Argentin
Adaptación a la sequÃa y necesidades hÃdricas de Eucalytus globulus Labill. en Huelva
Eucalyptus glubulus is a widely used species in forest plantations for wood production. It is adapted to live on poor soils under Mediterranean climate with oceanic influence. It supports some degree of water stress but not extreme temperatures exceeding 40 ºC or -5 ºC. Its cultivation in the province of Huelva is seriously limited by the frugality of the soils and the summer drought, and it is attacked by pests such as Phoracantha spp., particularly virulent under water stress conditions. In this work, we analyzed the results of several experiments, carried out in nurseries and in field plots, regarding to the
response of E. globulus clones to water stress and its water consumption needs. As for other biotic or abiotic stresses, the species showed genetic variability (at clonal level) in their resistance to water stress, which offers the possibility to further
develop and improve breeding programs. Under water stress conditions, it reacts by coming into play avoidance mechanisms (leaf morphology, stomatal closure, vulnerability to xylem cavitation, etc..) and tolerance mechanisms (osmotic and elastic
adjustment). However, the degree of variation of each of the above cited parameters differed between clones, showing different strategies among them. This can be used when establishing the selection criteria in relation to the purpose of each breeding program (resistance to be attacked by Phoracantha spp., production and water use efficiency, resistance to threshold values of water stress, etc.)Eucalyptus globulus Labill. es una especie ampliamente utilizada en plantaciones para producción de madera. Está adaptada a vivir sobre suelos pobres y bajo clima mediterráneo pero suave y con influencia oceánica. Soporta cierto grado de estrés hÃdrico pero le van mal temperaturas extremas que sobrepasen 40 ºC ó -5 ºC. Su cultivo en la provincia de Huelva está seriamente limitado por la frugalidad de los suelos y la sequÃa estival, asà como por el ataque de plagas, especialmente virulentas en situaciones de estrés hÃdrico como en el caso de Phoracantha spp. En este trabajo se muestra una recopilación de varias experiencias, llevadas a cabo en vivero y en parcelas de campo, sobre la reacción de los clones al estrés hÃdrico y sus necesidades de consumo de agua. Al igual que para otros tipos de estreses biótico o abióticos, la especie manifestó variabilidad genética (a nivel clonal) en su grado de resistencia al estrés hÃdrico, lo que ofrece la posibilidad de seguir desarrollando programas de selección y mejora de la especie destinada a plantaciones forestales. Dicha resistencia se
implementaba al ser expuestos a situaciones de estrés hÃdrico, poniendo en juego mecanismos de evitación (morfologÃa foliar, cierre estomático, vulnerabilidad a la cavitación del xilema, etc.) y de tolerancia (ajuste osmótico y elástico). No obstante
el grado de variación de cada uno de los parámetros medidos difirió entre los clones, manifestando distintas estrategias entre clones, lo que puede ser utilizado a la hora de establecer el criterio de selección en función del objetivo perseguido en cada
lÃnea de mejora (resistencia al ataque por Phoracantha spp., producción y eficiencia en el uso del agua, resistencia a valores crÃticos de estrés hÃdrico, etc.)
Biomass Yield and Economic, Energy and Carbon Balances of Ulmus pumila L., Robinia pseudoacacia L. and Populus × euroamericana (Dode) Guinier Short-Rotation Coppices on Degraded Lands under Mediterranean Climate
The steadily increasing demand for energy and concerns about climate change have prompted countries to promote the use of renewable energy sources, including lignocellulosic biomass. In this context, this work aims to assess the biomass production for energy purposes in crops with short rotation, as well as its effect on soil properties. Deciduous tree species were used, mainly Siberian elm (Ulmus pumila L.), black locust (Robinia pseudoacacia L.) and a hybrid poplar clone (Populus × euroamericana (Dode) Guinier, clone ‘AF2’). Four field trials were implemented, under two different types of Mediterranean climate, where highly productive taxa were tested, in addition to the mixed planting of a nitrogen-fixing species with a non-fixing one. Short-rotation coppices (SRCs) of these taxa yield about 12–14 t ha−1 year−1 of high-quality dry woody biomass, when fertilizers and irrigation water are supplied; generate 205–237 GJ ha−1 year−1 net and earnings of about EUR 1.5 per EUR 1 invested; and sequester into the soil 0.36–0.83 t ha−1 year−1 of C and 57 kg ha−1 year−1 of N. Therefore, these species raised as SRCs could improve degraded soils if the crop is properly managed, resulting in favorable economic, energy and CO2 emission balances. The use of mixed plantations can bring economic and environmental gains, and the biomass transformation into high-quality chips or pellets gives it added value