62 research outputs found
Flavonoid, Nitrate and Glucosinolate Concentrations in Brassica Species Are Differentially Affected by Photosynthetically Active Radiation, Phosphate and Phosphite
We evaluated the effects of phosphate (Pi-deficiency: 0.1 mM; Pi-sufficiency: 0.5 mM), phosphite (low-Phi: 0.1 mM; medium-Phi: 0.5 mM; and high-Phi: 2.5 mM), and two mean daily photosynthetically active radiations (lower PAR: 22.2 mol ⋅ m-2 ⋅ d-1; higher PAR: 29.7 mol ⋅ m-2 ⋅ d-1), as well as their interactions, on flavonoid, nitrate and glucosinolate (GL) concentrations and growth characteristics in hydroponically grown Brassica campestris cv. Mibuna Early and Brassica juncea cv. Red Giant. As expected, higher PAR increased dry matter and contrariwise decreased number of leaves but only in B. campestris. Total flavonoid and individual flavonoid compounds increased with the higher PAR value in B. campestris. Pi-sufficiency resulted in a lower quercetin concentration in both species, the isorhamnetin and total flavonoid concentrations in B. campestris, and the cyanidin concentration in B. juncea, in comparison to Pi-deficiency. Similarly, Pi-sufficient plants exhibited lower GL concentration, especially alkyl-GLs in B. campestris and alkenyl-GLs and an aryl-GL in B. juncea. Pi did not affect the nitrate concentration in either species, and nor did Phi influence the flavonoid concentrations in either species. In B. campestris, medium Phi (0.5 mM) increased the 1-methoxyindol-3-ylmethyl GL concentration by 28.3%, as compared to that observed at low Phi. In B. juncea, high Phi level increased the but-3-enyl-GL concentration by 18.9%, in comparison to values recorded at medium Phi. B. campestris plants exposed to higher PAR increased total flavonoids concentration. In both Brassica species, higher PAR stimulated the alkyl-, alkenyl-, and indole-GLs. The interaction of lower PAR and increasing Phi significantly decreased flavonoid concentration in B. juncea, whereas increasing Phi at higher PAR increased such concentration in this species. The same combination reduced the concentration of 2-phenylethyl- and indol-3-ylmethyl-GL in B. juncea. The highest indol-3-ylmethyl-GL concentration was observed when Pi was deficient combined with medium Phi in B. juncea. Thus, PAR, Pi and Phi may modulate flavonoid, GL and nitrate concentrations in Brassica species, which may be a useful tool to improve the nutraceutical quality of these leafy vegetables if properly managed
Nuevas variedades de caña de azúcar (Saccharum spp.) generadas por el Colegio de Postgraduados para el trópico húmedo mexicano
La caña de azúcar (Saccharum spp.) es el cultivo de mayor productividad a nivel mundial, y México se ubica como el sexto productor de azúcar y de caña de azúcar en el mundo
Glucosinolates: Structure, classification, biosynthesis and functions in higher plants
ABSTRACT
Objective: To analyze concepts, structure, classification, biosynthesis and functions of glucosinolates (GSLs) in higher plants.
Design/methodology/approach: A search was performed into recent high-impact literature related to glucosinolates (GSLs).
Results: GSLs are secondary metabolites rich in N and S. They are divided into aliphatic, aromatic, and indole GSLs depending on the amino acid from which they arise. The products of their hydrolysis, mediated by thioglucoside glucohydrolase, thioglucosidase or myrosinase enzymes (EC 3.2.1.147), play a role in increasing tolerance to biotic and abiotic stress factors. Furthermore, given their composition, they can serve as a nutrient reservoir under nutrient deficiency conditions.
Limitations on study/implications: GSLs are synthesized only in species of the Capparidaceae, Brassicaceae, Resedaceae, and Moringaceae families.
Findings/conclusions: GSLs are sulfur compounds that can serve as defense mechanisms against biotic and abiotic stress factors and as sources of nutrients in plants, and molecules with important nutraceutical properties in food and human health.Objective: To analyze concepts, structure, classification, biosynthesis and functions of glucosinolates (GSLs)in higher plants.Design/methodology/approach: A search was performed into recent high-impact literature related toglucosinolates (GSLs).Results: GSLs are secondary metabolites rich in N and S. They are divided into aliphatic, aromatic, andindole GSLs depending on the amino acid from which they arise. The products of their hydrolysis, mediated bythioglucoside glucohydrolase, thioglucosidase or myrosinase enzymes (EC 3.2.1.147), play a role in increasingtolerance to biotic and abiotic stress factors. Furthermore, given their composition, they can serve as a nutrientreservoir under nutrient deficiency conditions.Limitations on study/implications: GSLs are synthesized only in species of the Capparidaceae, Brassicaceae,Resedaceae, and Moringaceae families.Findings/conclusions: GSLs are sulfur compounds that can serve as defense mechanisms against bioticand abiotic stress factors and as sources of nutrients in plants, and molecules with important nutraceuticalproperties in food and human health
La exposición de plantas de arroz (Oryza sativa L.) a nanopartículas de plata afecta la expresión de genes multifuncionales NAC
Objective: We aimed to evaluate the effect of silver nanoparticles (AgNPs) on the expression of 17 NAC genes in rice plants (Oryza sativa L.) under greenhouse conditions.
Methodology: Twelve-d-old rice seedlings were transferred to a hydroponic system. Fourteen days after the transplant, the following treatments were applied through the nutrient solution: 0, 20, 40 and 80 mg L-1 AgNPs. Each solution had six repetitions which were distributed in a completely randomized experimental design. From the treated and control plants, total RNA was extracted from stems, from which cDNA was synthesized and a measurement of gene expression was performed by the qRT-PCR technique. The elongation factor 1?, which showed greater stability, was taken as the reference gene. The relative expression of the genes was determined using the 2-??Ct method, with a differential expression value of 2.
Results: It was found that the AgNPs induced the expression of four NAC genes (Os02g56600, Os07g04560, Os12g43530 and Os06g5107) by at least one dose of AgNPs tested, and one gene (0s08g10080) showed repression of expression by the presence of these nanoparticles in the nutrient solution. In the Os07g04560 gene, the expression was dependent on the concentration of AgNPs, that is, the higher the concentration of AgNPs in the medium, the greater the expression of the gene.
Limitations: In further studies, it would be necessary to explore the expression of more NAC genes in different tissues and phenological stages of the plant.
Conclusions: It is concluded that silver nanoparticles differentially affect the expression of NAC genes in rice, which confirms the multifunctionality of these genes in plants.Objetivo: El objetivo de este estudio fue evaluar el efecto de las nanopartículas de plata (AgNPs) en la expresión de 17 genes NAC en plantas de arroz (Oryza sativa L.) en invernadero. Plántulas de arroz de 12 d de edad se trasfirieron a un sistema hidropónico. Catorce días después del trasplante se aplicaron los siguientes tratamientos a través de la solución nutritiva: 0, 20, 40 y 80 mg L-1 AgNPs. Cada tratamiento tuvo seis repeticiones en un diseño experimental completamente al azar. De las plantas tratadas y del testigo se extrajo RNA total de vástago, a partir del cual se sintetizó cDNA y se realizó una medición de la expresión génica por la técnica de qRT-PCR. Como gen de referencia se tomó el Factor de elongación 1?, que mostró mayor estabilidad. La expresión relativa de los genes se determinó utilizando el método 2-??Ct, con un valor de expresión diferencial de 2.
Resultados: Se encontró que las AgNPs indujeron la expresión de cuatro genes NAC (Os02g56600, Os07g04560, Os12g43530 y Os06g5107) por al menos una dosis de AgNPs probada, y un gen (0s08g10080) mostró represión de la expresión por la presencia de estas nanopartículas en la solución nutritiva. En el gen Os07g04560, la expresión fue dependiente de la concentración de AgNPs, esto es, a mayor concentración de AgNPs en el medio, mayor expresión del gen.
Limitaciones: En este estudio no fue posible analizar la expresión de genes NAC en respuesta a AgNPs en otros tejidos y en otras etapas fenológica.
Conslusiones: Las nanopartículas de plata afectan diferencialmente la expresión de genes NAC en arroz, lo que corrobora la multifuncionalidad de estos genes en plantas
Exploitation of plantain (Musa spp.) plantations as an agrotourist element
Objective: To publicize the processes and alternative uses that plantain cultivation may have, in addition to places with tourist potential in the town of Monte Salas, Fortín de las Flores, Veracruz, Mexico
Design / Methodology / Approach: A methodology based on stages was carried out where a compression of the space of the study area was made, anthropological analysis, description of the process of the banana leaf, commercial analysis, development of a sustainable product and a bonding stay in the country of Colombia
Results: In the town of Monte Salas, Fortín, de las Flores Veracruz, Mexico, plantain cultivation was analyzed as an outstanding element of the landscape, together with the process of leaf roast production as a value-adding strategy to generate biodegradable co-products. Through the dissemination of audiovisual capsules on social networks, places with tourist potential were made known and together with the implementation of the offer of biodegradable co-products, it was demonstrated that banana leaf can be used alternately.
Study limitations / implications: Due to the health contingency experienced, it was not possible to carry out a workshop programmed for the locality.
Conclusions: Making it known that new products can be created that are biodegradable and that have no impact on the environment brought with it the acceptance of creating the dishes made with the leaf, and also its successful implementation in the tourist field I believe the possibility for tourists to come to the town of Monte Salas, Fortín de las Flores, Veracruz, Mexico to discover its agro-systemic landscape.Objective: To analyze the processes and alternative uses that plantain cultivation may have, in addition toplaces with tourist potential in the town Monte Salas, municipality of Fortín de las Flores, Veracruz, Mexico.Design/Methodology/Approach: A review of the space of the study area was performed, as well as ananthropological analysis, description of the process of the plantain leaf used to prepare local food, commercialanalysis, development of a sustainable product, and a research stay in Colombia.Results: In Monte Salas, Fortín de las Flores, Veracruz, Mexico, plantain cultivation is regarded as anoutstanding element of the landscape, together with the process of leaf roast production as a value-addingstrategy to generate biodegradable co-products. Through the dissemination of audiovisual capsules on socialnetworks, places with tourist potential were made known and together with the implementation of the offer ofbiodegradable co-products, it was demonstrated that plantain leaf can be used alternately.Study Limitations/Implications: Due to the SARS-CoV-2 (COVID-19) coronavirus pandemic, the dissemination of our findings and products were restricted.Conclusions: Novel biodegradable products can be manufactured from plantain leaves, which created aspecial interest of local tourists to visit Monte Salas and enjoy the agrosystemic landscape
Advances in the selection program of sugarcane (Saccharum spp.) varieties in the Colegio de Postgraduados
Objective: To describe the advances in the sugarcane variety selection program that is carried out by the Campus Córdoba of the College of Postgraduates in Agricultural Sciences located in Amatlán de los Reyes, Veracruz, Mexico.
Design/methodology/approach: For the selection of sugarcane varieties, the methodology developed by the Institute for the Improvement of Sugar Production (IMPA) was used, and for the varietal description, the protocol of the International Union for the Protection of New Varieties of Plants (UPOV) was implemented.
Results: In 2009, the Campus Córdoba started the varietal selection program with more than 6 thousand hybrids from 40 crosses, of which 4422 materials were selected after showing resistance to the sugarcane mosaic virus. From the 4422 materials of the seedling phase, 352 clones were selected and evaluated in the Furrow Phase, selecting 57 varieties for the Plot Phase. Of these 57 varieties, 36 were selected in the Adaptability Test Phase, and 27 in the following Agroindustrial Evaluation Phase. Of these last 27 varieties, estimated yields are greater than 100 t ha-1, with good quality of juices and agronomic characteristics.
Study limitations/implications: The program has faced climate and budget challenges, delaying progress. Currently, the Covid-19 pandemic has drastically affected our research.
Findings/conclusions: This breeding and variety selection program started with 6,000 crosses, of which to date there are 27 in advanced stages of selection, with the possibility of adaptation and good yields for the area of influence of the Campus Córdoba.Objective: To describe the advances in the sugarcane variety selection program that is carried out by the Campus Córdoba of the College of Postgraduates in Agricultural Sciences located in Amatlán de los Reyes, Veracruz, Mexico.
Design/methodology/approach: For the selection of sugarcane varieties, the methodology developed by the Institute for the Improvement of Sugar Production (IMPA) was used, and for the varietal description, the protocol of the International Union for the Protection of New Varieties of Plants (UPOV) was implemented.
Results: In 2009, the Campus Córdoba started the varietal selection program with more than 6 thousand hybrids from 40 crosses, of which 4422 materials were selected after showing resistance to the sugarcane mosaic virus. From the 4422 materials of the seedling phase, 352 clones were selected and evaluated in the Furrow Phase, selecting 57 varieties for the Plot Phase. Of these 57 varieties, 36 were selected in the Adaptability Test Phase, and 27 in the following Agroindustrial Evaluation Phase. Of these last 27 varieties, estimated yields are greater than 100 t ha-1, with good quality of juices and agronomic characteristics.
Study limitations/implications: The program has faced climate and budget challenges, delaying progress. Currently, the Covid-19 pandemic has drastically affected our research.
Findings/conclusions: This breeding and variety selection program started with 6,000 crosses, of which to date there are 27 in advanced stages of selection, with the possibility of adaptation and good yields for the area of influence of the Campus Córdoba
Metabolic role of the enzyme pyruvate phosphate dikinase in transgenic tobacco plants
TITELBLATT UND INHALTVERZEICHNIS
EINLEITUNG
ZIELSETZUNG
MATERIAL UND METHODEN
ERGEBNISSE
DISKUSSION
ZUSAMMENFASSUNG
ABSTRACT
LITERATURVERZEICHNIS
ANHANGIn Rahmen dieser Arbeit wurden verschiedenen PPDK-überexprimierende
Tabaklinien untersucht. Die PPDK wurde entweder unter der Kontrolle des 35S-
Promotors bzw. des wurzelspezifischer B33-Promotors im Cytosol oder alternativ
in den Plastiden überexprimiert (Sheriff, 1994; Stenzel, 1997). In ersten Teil
der vorliegenden Arbeit wurde der Einfluss unterschiedener Stickstoffquelle
auf das Wachstum und Produktivität der transgenen Tabaklinien und des Wildtyps
untersucht. Stickstoff wurde als eine Kombination von Nitrat und Ammonium (20%
des gesamten Stickstoffs als Ammonium); Nitrat (einzige N-Form) oder Ammonium
(einzige N-Form) gegeben. Außerdem wurde eine N-defizitäre Lösung (3 mM NO3-)
als Kontrolle genommen. Die Mutanten zeigten im Vergleich zum Wildtyp ein
signifikant höheres Wachstum bei Stickstoffangebot und eine Reduktion des
Wachstums. Die transgenen Pflanzen zeigten eine erhöhte Toleranz für Ammonium
als einzige Stickstoffquelle. Der Samenertrag war in den transgenen
Tabakpflanzen höher als beim Wildtyp. Es ist anzunehmen, dass die Steigerung
von Wachstum und Samenertrag in den PPDK-Transformanden durch eine verbesserte
Bereitstellung von C-Skeletten für die Aminosäuresynthese bewirkt wird. Die
reversible PPDK-Reaktion wird in den Plastiden durch die hohe Pyrophosphatase-
Aktivität in Richtung Phosphoenolpyruvat (PEP) gezogen. PEP dient als Substrat
zur Bildung von Oxalacetat (OAA) durch die PEP-Carboxylase. OAA kann in einer
anaplerotischen Reaktion den Zitrat-Zyklus auffüllen oder direkt zu Malat
reduziert werden. Die Ergebnisse der die PPDK im Cytosol überexprimierenden
Linien zeigten, dass die PPDK-Reaktion im Cytosol auch in die Richtung der
PEP-Synthese läuft. In zweiten Teil der Arbeit wurde die Al-Toleranz der
transgenen Tabakpflanzen in Vergleich zum Wildtyp untersucht. Die Daten deuten
darauf hin, dass die Aluminium-Toleranz der Transformanden durch erhöhte
Abgabe von organischen Säuren aus der Wurzel verursacht wird. Diese bilden
einen Komplex mit dem Metallkation und vermindern so die Aufnahme in die
Wurzel. Die PPDK erhöht die Säureextrusion durch die Bereitstellung von
Phosphoenolpyruvat (PEP), das durch PEP-Carboxylase katalysierte
Carboxylierung Oxalacetat als Vorstufe der organischen Säuren liefert. Unsere
Ergebnisse lassen darauf schließen, dass beim Wildtyp zumindest unter
Aluminium-Stress ein Engpass bei der Bereitstellung von PEP besteht, der in
den PPDK-Transformanden verringert oder aufgehoben wird. Da die Transformation
mit PPDK ansonsten keinen nachteiligen Phänotyp verursacht, sondern im
Gegenteil noch Wachstum und Samenertrag bei Stickstoffdüngung verbessert,
scheint sie eine gute Möglichkeit darzustellen, die Aluminium-Toleranz von
Pflanzen zu verbessern.Transgenic tobacco plants overexpressing the M. crystallinum PPDK gene were
studied. Four different construct were generated, using two different
promoters (CaMV-35S and B33) and two different cDNA sequences (one directed to
plastids, the other to the cytosol) (Sheriff, 1994; Stenzel, 1997). The effect
of nitrogen on the behaviour of transgenic and wild type tobacco plants was
tested during the first experiments. Treatments included a combination of
nitrate and ammonium (20% of the total nitrogen as ammonium); nitrate (as only
N-form supplied) and ammonium (as the only N-form supplied). Control plants
received a solution low in N (3 mM NO3-). The mutants showed a significant
higher growth when grown in nitrogen, whereas at low N supply their growth was
reduced in comparison to the wild-type. Transgenic plants showed stronger
tolerance to ammonium in comparison to the wild-type. Seed yield in transgenic
plants was higher in comparison to the wild-type. This suggests that the
increase in growth and seed production in transgenic plants may be the result
of a better supply of C-chains for the formation of amino acids. In the
plastids the reversible PPDK-reaction is shifted in direction to
phosphoenolpyruvate (PEP) because of the high pyrophosphatase-activity. PEP
serves as substrate for the formation of oxalacetate (OAA) by the PEP-
carboxylase. OAA can be incorporated into the citric acid cycle or directly
reduced to malate. The results observed on transgenic lines showed that the
PPDK-reaction in the cytosol leads to PEP-synthesis. Transgenic tobacco plants
and the wild-type where further analyzed to elucidate their growth response in
the presence of Aluminium (Al). The data indicates that Al tolerance observed
in transgenic plants was increased via exudation of organic acids in the
roots. Organic acids complex the Al, avoiding it uptake by roots. In wild-type
plants, at least under Al stress conditions, supply of PEP may be more
difficult. As overexpression of PPDK causes no visible phenotypical changes,
but improves productivity and growth under a good nitrogen supply, PPDK may
represent a possibility to increase tolerance to Al stress in plants
Caracterización de los productores de alcatraz blanco en La Perla, Veracruz
In Mexico, the white alcatraz (Zantedeschia aethiopica (L) K.
Spreng) is considered a minor crop of cut flowers grown in the
central region of the state of Veracruz. The aim of this study
was to determine the status of the producers of alcatraz in the
town of La Perla, Veracruz. The research method consisted of
a survey by a questionnaire sent to a representative sample of
producers in this county alcatraz. The results show that 53%
of producers are people who have low levels of schooling,
see no need to belong to an association, more than 80% of
farmers consider it a very profitable business; have become
associated with other plants alcatraz to strengthen their
economy. Ongoing training on agronomic crop management
is recommended to provide a comprehensive management
plants, focus to combat and eradicate "soft rot", the main
phytosanitary problem, coupled with the traditional system
of production, lack of investment and value additionEn México, el alcatraz blanco (Zantedeschia aethiopica
(L) K. Spreng) es considerado como un cultivo menor
de flores de corte, cultivada en la zona centro del estado
de Veracruz. El objetivo de este trabajo fue determinar la
situación de los productores de alcatraz en el municipio de
La Perla, Veracruz. El método de investigación consistió
en la aplicación de una encuesta mediante un cuestionario
dirigido a una muestra representativa de productores de
alcatraz en este municipio. Los resultados muestran que
53% de los productores son personas que tienen bajo
nivel de escolaridad, no consideran necesario pertenecer
a alguna asociación, más de 80% de los productores lo
considera un negocio poco rentable; han ido asociando
el alcatraz con otras plantas para fortalecer su economía
familiar. Se recomienda capacitación permanente sobre
el manejo agronómico del cultivo, dar un manejo integral
a las plantas, enfocarse al combate y erradicación de la
�pudrición blanda�, principal problema fitosanitario,
aunado al sistema tradicional de producción, la falta de
inversión y agregación de valo
Seedlings growth rates of lulo (Solanum quitoense [Lamarck.]) In organic substrates
Lulo (Solanum quitoense [Lamarck.]) is a species with high
potential for global marketing because of the nutritional
value of its fruit. In Mexico, research on this species is
scarce and one of the first challenges is to obtain vigorous
seedlings to ensure yield and good fruit quality. In this
research, growth rates lulo seedlings from germinated seeds
and grown in three organic substrates made of peat and
compost in different ratios (60/40, 40/60 and 20/80, v/v) in the
greenhouse were estimated. The experiment had a distribution
completely randomized design with four replications, and
the experimental unit contained 32 seedlings. Leaf area
ratio (RAF), specific leaf area (SLA), leaf ratio (PH) and
root ratio (PR): sixty days after sowing growth, data direct
for the estimation of the following indexes were taken. The
data obtained were analysed statistically with an analysis of
variance and mean comparison test. The results indicated that,
the compost in higher proportion in the substrate reduces the
RAF, the AFE and PH; on the other hand, increases the PR.
Adding compost to the substrate in proportion 80%, negatively
affected growth rates of seedlings of lulo due to increased
electrical conductivity, and Na+
, Cl-
and HCO3
-
soluble in the
substrate. It is concluded that, the compost can be used with
satisfactory results in the production of lulo seedlings in
combination with peat, in equal or less than 60%.El lulo (Solanum quitoense [Lamarck.]) es una especie con
alto potencial de comercialización a nivel global dado el valor
nutritivo de sus frutos. En México, la investigación sobre esta
especie es escasa y uno de los primeros retos es la obtención
de plántulas vigorosas que garanticen rendimiento y buena
calidad de frutos. En esta investigación se estimaron índices
de crecimiento de plántulas de lulo provenientes de semillas
germinadas y crecidas en tres sustratos orgánicos constituidos
por turba y composta en diferentes relaciones (60/40, 40/60
y 20/80, v/v) en invernadero. El experimento tuvo una
distribución completamente al azar con cuatro repeticiones,
y la unidad experimental contenía 32 plántulas. Sesenta días
después de la siembra se tomaron datos directos de crecimiento
para la estimación de los índices siguientes: razón de área
foliar (RAF), área foliar específica (AFE), proporción de hoja
(PH) y proporción de raíz (PR). Los datos obtenidos fueron
analizados estadísticamente, realizando un análisis de varianza
y una prueba de comparación de medias. Los resultados indican
que la composta en mayor proporción en el sustrato reduce
la RAF, el AFE y PH; por el contrario, incrementa la PR. La
adición de composta al sustrato en proporción 80%, afectó
negativamente los índices de crecimiento de las plántulas de
lulo debido al incremento en la conductividad eléctrica, y de
Na+
, Cl-
y HCO3
- solubles, en el sustrato. Se concluye que la composta puede ser usada con resultados satisfactorios, en la
producción de plántulas de lulo, en combinación con turba, en
proporciones iguales o menores a 60%
GridPP DIRAC: Supporting non-LHC VOs on LHC centric resources
To allow non-LHC communities access to the primarily LHC dominated resources of the grid, the GridPP consortium in the UK maintains a multi-VO DIRAC service for this user-base. After an extensive testing phase, this service has been in production for the last two years and has been fully integrated into the user communities’ workflows. We report on the approaches taken by the VOs and the insights gained from these
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