scholarly journals Covalent labelling of the NADPH: protochlorophyllide oxidoreductase from etioplast membranes with [3H]N-phenylmaleimide

1981 ◽  
Vol 195 (1) ◽  
pp. 93-101 ◽  
Author(s):  
R P Oliver ◽  
W T Griffiths
Keyword(s):  
Hordeum Vulgare ◽  
Avena Sativa ◽  
Ternary Complex ◽  
Thiol Groups ◽  
Protochlorophyllide Oxidoreductase ◽  
Protochlorophyllide Reductase ◽  
Enzyme Substrates ◽  
Specific Manner ◽  
Etioplast Membranes ◽  
Single Peptide

[3H]N-Phenylmaleimide has been used to covalently label in a specific manner the substrate-protected thiol groups of the enzyme protochlorophyllide reductase. In membrane preparations from oat (Avena sativa) and runner-bean (Phaseolus vulgaris) seedlings, two related peptides of mol.wts. 35000/37000 and 34000/35000 respectively and showing properties expected of the reductase have been identified, whereas the same technique with barley (Hordeum vulgare) extracts resulted in labelling a single peptide of mol.wt. 38000. Evidence is presented that both NADPH and protochlorophyllide are required for protection of the essential thiol groups on the reductase in oat extracts, a situation favouring a ternary complex as the structure for the photoactive enzyme--substrates intermediate.

scholarly journals Substrate-specificity studies on protochlorophyllide reductase in barley (Hordeum vulgare) etioplast membranes

1980 ◽  
Vol 186 (1) ◽  
pp. 267-278 ◽  
Author(s):  
W T Griffiths
Keyword(s):  
Carboxylic Acid ◽  
Methyl Ester ◽  
Hordeum Vulgare ◽  
Substrate Specificity ◽  
Acid Group ◽  
Carboxylic Acid Group ◽  
Naturally Occurring ◽  
Protochlorophyllide Reductase ◽  
Nickel Copper ◽  
Etioplast Membranes

1. The substrate specificity of the enzyme protochlorophyllide reductase in barley (Hordeum vulgare) etioplasts was investigated. 2. It was shown that naturally occurring esterified protochlorophyllide and chemically prepared protochlorophyllide methyl ester are not substrates for the enzyme, suggesting an important role for the C-7 carboxylic acid group in binding of the porphyrin to the enzyme. 3. Removal of magnesium from the protochlorophyllide leads to inactivity of the compound as a substrate for the enzyme. However, activity can be restored by replacing the magnesium with zinc, whereas nickel, copper or cobalt failed to restore substrate activity. 4. Binding of the second substrate, NADPH, to the enzyme probably occurs through the 2'-phosphate group in the coenzyme.

Competitive attributes ofA. sativa, T. aestivum, andH. vulgareare conserved in no-till cropping systems

Weed Science ◽  
1999 ◽  
Vol 47 (6) ◽  
pp. 712-719 ◽  
Author(s):  
Anne Légère ◽  
Yuguang Bai
Keyword(s):  
Hordeum Vulgare ◽  
Avena Sativa ◽  
Growth Parameters ◽  
Cropping Systems ◽  
Seedling Emergence ◽  
Biomass Accumulation ◽  
Tillage Systems ◽  
Area Index ◽  
No Till ◽  
Lower Test

The robustness of competitive attributes of cereals such as rapid and uniform seedling emergence, tillering, early biomass accumulation and canopy closure, and height advantage over weeds have not yet been tested under environmental conditions typical of no-till (NT) cropping systems. Our objective was to evaluate the effects or NT practices on growth and productivity ofAvena sativa, Triticum aestivum, Hordeum vulgare, and associated weeds. The experiment was conducted on a Kamouraska clay at La Pocatière, QC, in 1994, 1995, and 1996.Avena sativa, T. aestivum, andH. vulgarewere grown under tilled and NT practices. Cereal growth parameters were measured six (1994) or seven (1995) times between planting and the 11th week after planting but only once in 1996. Grain yields and yield components were determined at crop maturity.Avena sativaandH. vulgarepopulations were little affected by tillage, whereasT. aestivumpopulations were reduced by 16 to 20% in NT systems. Growth in height in NT systems was either similar or greater than in tilled systems in all three cereals. Cereal leaf area index (LAI) and biomass accumulation was also comparable between tillage systems, except forT. aestivumLAI in 1994, which was greater in tilled plots on two sampling dates. Response of annual dicots to tillage was inconsistent in all crops. Annual monocots dominated in some but not all NT systems. Perennial dicots dominated in NT systems, whereas perennial monocots were more abundant in tilled systems in all three cereals.Avena sativaandT. aestivumyields in NT plots were comparable or greater than in tilled plots, in spite of having either lower test weights (A. sativa) or lower 1,000-grain weights (T. aestivum). NTT. aestivumproductivity was maintained in spite of reduced plant establishment.Hordeum vulgareyields were also similar across tillage systems, except in 1995, when yields in tilled plots were greater than in NT plots. The height advantage observed for NTH. vulgaredid not result in improved yields. All three cereals, and particularlyA. sativa, appeared well suited to NT systems, despite the pressure provided by different weed groups, compared to tilled systems. However, results suggest that NT production of cereals could benefit from improved attention to perennial dicot control and crop seedling establishment, particularly forT. aestivum.

scholarly journals Light modulation of the activity of protochlorophyllide reductase

1980 ◽  
Vol 189 (1) ◽  
pp. 125-133 ◽  
Author(s):  
R E Mapleston ◽  
W T Griffiths
Keyword(s):  
Light Modulation ◽  
Protochlorophyllide Oxidoreductase ◽  
Constant Illumination ◽  
Protochlorophyllide Reductase ◽  
Etiolated Plants

Illumination of etiolated plants effects the activity of protochlorophyllide reductase (NADPH-protochlorophyllide oxidoreductase) in the plastids. Constant illumination or a 2-min light-triggering of etiolated plants leads to an approx. 80% decrease in activity of the enzyme, a change that can be reversed by returning the plants to darkness. The change in activity results from an alteration of the Vmax. rather than Km. Despite the fact that exogenous pigments effect the activity of the enzyme in vitro, no correlation could be drawn between the concentrations of pigments in vivo and activity of the enzyme.

Pseudomonas syringae pv. striafaciens. [Distribution map].

1987 ◽  
Author(s):  
Keyword(s):  
Hordeum Vulgare ◽  
North America ◽  
South America ◽  
Geographical Distribution ◽  
Pseudomonas Syringae ◽  
Avena Sativa ◽  
New South ◽  
Distribution Map ◽  
South Wales ◽  
New Distribution

Abstract A new distribution map is provided for Pseudomonas syringae pv.striafaciens (Elliott) Young, Dye & Wilkie. Hosts: Oats (Avena sativa) and barley (Hordeum vulgare). Information is given on the geographical distribution in Africa, Zimbabwe, Asia, Japan, Korea, Australasia & Oceania, Australia, New South Wales, Queensland, Europe, Germany, USSR, North America, Canada, Alberta, Manitoba, Ontario, Saskatchewan, Mexico, USA, South America, Argentina, Colombia.

scholarly journals EVALUACIÓN AGRONÓMICA DE CEREALES FORRAJEROS DE USO POTENCIAL EN SISTEMAS DE PRODUCCIÓN DE LECHE DE ALTURA

2019 ◽  
Vol 3 (1) ◽  
pp. 72-77
Author(s):  
María Mesén ◽  
William Sánchez
Keyword(s):  
Triticum Aestivum ◽  
Hordeum Vulgare ◽  
Avena Sativa

La presente investigación se realizó en el año 1996, en el distrito Cot, cantón Oreamu-no, provincia Cartago. La topografía de la finca es irregular y se ubica a una altitud de 2.100 msnm. El objetivo del estudio fue evaluar la adaptabilidad de una colección de 13 ce-reales forrajeros, nueve variedades de Avena (Avena sativa), tres de Trigo (un Triticum se-cale y dos Triticum aestivum) y una de Cebada (Hordeum vulgare). El diseño experimental utilizado, fue de bloques completos al azar, con tres repeticiones, representando cada cul-tivar un tratamiento. Las variables evaluadas fueron: cobertura, altura, plagas, producción de biomasa y valor nutritivo. En cuanto a las variables cobertura y altura los valores fueronaltos en todos los cultivares cosechados, superiores a 90% y 75 cm respectivamente, losTriticum y la Hordeum vulgare fueron inferiores a las avenas en ambos aspectos. La única enfermedad que se presentó fue la Puccinia sp. eliminando por completo las avenas Ne-huén, Dula, Gaviota y Llaofén y afectando levemente (5% del follaje afectado) los cereales Culgoa II, Águila y Triticum secale. Los demás cereales no fueron dañados por ninguna pla-ga. La producción de biomasa en los diferentes cultivares osciló en un rango de 6,8 y 15,5 t/ha/corte. El análisis de varianza para esta variable mostró diferencias entre cultivaresP=0,01 y P=0,001 para t/ha/corte y tasa de crecimiento respectivamente. Según los altos rendimientos de materia seca, adecuado valor nutritivo y ausencia de plagas, se puede con-cluir que los cereales que mejor se adaptaron a la zona en estudio fueron las avenas Riel, Nobby y Amby. Se debe continuar investigando con los cultivares sobresalientes bajo pas-toreo y en sustitución de alimentos balanceados.

Wheat dwarf virus. [Distribution map].

2018 ◽  
Author(s):  
Keyword(s):  
Triticum Aestivum ◽  
Czech Republic ◽  
Hordeum Vulgare ◽  
Avena Sativa ◽  
Dwarf Virus ◽  
Wheat Dwarf Virus ◽  
Distribution Map ◽  
Virus Distribution ◽  
New Distribution ◽  
Distribution In Europe

Abstract A new distribution map is provided for Wheat dwarf virus. Geminiviridae: Mastrevirus. Hosts: wheat (Triticum aestivum), barley (Hordeum vulgare), oat (Avena sativa). Information is given on the geographical distribution in Europe (Austria, Bulgaria, Czech Republic, Finland, France, Germany, Hungary, Italy, Poland, Romania, Slovakia, Slovenia, Spain, Sweden, UK, Ukraine), Asia (China, Hebei, Qinghai, Shaanxi, Shanxi, Sichuan, Yunnan, Iran, Syria, Turkey), Africa (Tunisia Zambia).

Simazine-Induced Nitrate Absorption Related to Plant Protein Content

Weed Science ◽  
1972 ◽  
Vol 20 (6) ◽  
pp. 569-572 ◽  
Author(s):  
S. K. Ries ◽  
V. Wert
Keyword(s):  
Hordeum Vulgare ◽  
Plant Growth ◽  
Avena Sativa ◽  
Protein Concentration ◽  
Nitrate Uptake ◽  
Kinetic Studies ◽  
Regression Analyses ◽  
Plant Weight ◽  
Companion Plants ◽  
Nutrient Solutions

Barley(Hordeum vulgareL. ‘Coho’), rye(Secale cerealeL. ‘MSU Exp.’) and oat(Avena sativaL. ‘Gary’) seedlings were grown in nutrient solutions containing 0 and 10−9to 10−7M concentrations of 2-chloro-4,6-bis(ethylamino)-s-triazine (simazine). In kinetic studies with rye and barley seedlings, simazine increased water and nitrate uptake after 3 days' exposure to 10−9M simazine compared to controls; there was no effect from 10−7M simazine. The effect was manifested in an increase in both plant weight and total protein. After 12 days, companion plants treated with 10−7M simazine were the same size as controls but contained a higher protein concentration especially in the shoots. Regression analyses showed that the simazine-induced increases in total nitrogen content of the three grain species were closely related to the nitrate and water uptake, whether manifested by greater plant growth or more protein per gram of plant.

scholarly journals Transmisión experimental del virus del mal de Río Cuarto por Delphacodes kuscheli

2001 ◽  
Vol 26 (1) ◽  
pp. 39-44 ◽  
Author(s):  
GRACIELA A. TRUOL ◽  
TOMIO USUGI ◽  
JUTARO HIRAO ◽  
JOEL D. ARNEODO ◽  
M. PAZ GIMÉNEZ PECCI ◽  
...  
Keyword(s):  
Triticum Aestivum ◽  
Zea Mays ◽  
Hordeum Vulgare ◽  
Secale Cereale ◽  
Avena Sativa ◽  
Chloris Gayana ◽  
Delphacodes Kuscheli ◽  
Phalaris Canariensis

Entre las enfermedades que afectan al cultivo de maíz (Zea mays) en Argentina, la producida por el virus del mal de Río Cuarto (MRCV) es la más importante. El MRCV pertenece a la familia Reoviridae, género Fijivirus, y su propagación en la naturaleza es realizada por Delphacodes kuscheli (Hemiptera: Delphacidae). La modalidad de transmisión para los miembros de este género de virus es persistente propagativa. Se estableció la necesidad de ajustar un sistema de transmisión eficiente del virus para estudios de caracterización, partiendo de poblaciones libres de virus criadas en laboratorio, para lo cual se ensayaron distintos períodos de adquisición, latencia e inoculación, evaluándose además un rango de hospedantes diferenciales. Se lograron obtener insectos libres de virus en cantidad suficiente para llevar a cabo los trabajos, mediante su cría en fitotrones y cámaras aclimatadas. La transmisión experimental del MRCV se efectuó exitosamente, bajo idénticas condiciones, empleando períodos de adquisición, latencia e inoculación de dos, 10 y uno día respectivamente para los cereales de grano fino y de dos, 10 y dos días para el maíz. Se infectaron de este modo las siguientes especies: maíz, cebada (Hordeum vulgare), avena (Avena sativa), trigo (Triticum aestivum), centeno (Secale cereale), grama rhodes (Chloris gayana) y alpiste (Phalaris canariensis). La detección del virus en las plantas inoculadas se efectuó mediante pruebas serológicas, análisis de dsRNA en electroforesis en gel de poliacrilamida (obteniéndose las 10 bandas típicas de los fijivirus) y microscopía electrónica, detectándose las partículas isométricas de entre 60 y 70 nm de diámetro.

Absorption and Dissipation of TCA by Wheat and Oats

Weed Science ◽  
1970 ◽  
Vol 18 (4) ◽  
pp. 492-496 ◽  
Author(s):  
Paul N. P. Chow
Keyword(s):  
Triticum Aestivum ◽  
Zea Mays ◽  
Hordeum Vulgare ◽  
Avena Sativa ◽  
Trichloroacetic Acid ◽  
Potassium Cyanide ◽  
Dichlorophenoxyacetic Acid ◽  
Wheat Seedlings ◽  
The Difference ◽  
2,4 Dichlorophenoxyacetic Acid

In the greenhouse, five crops were grown in soil containing trichloroacetic acid (TCA) at 3 to 24 ppm. Based on seedling yields, corn (Zea mays L., var. Morden 88) and oats (Avena sativa L., var. Rodney) were relatively tolerant to TCA at all rates, barley (Hordeum vulgare L., var. Conquest) and rye (Secale cereale L., var. Antelope) were tolerant at lower rates, but wheat (Triticum aestivum L., var. Manitou) suffered injury at all rates. When TCA-2-14C was applied to the roots of wheat and oats seedlings in water or nutrient solution, wheat seedlings absorbed more TCA-2-14C than oats. Potassium cyanide (KCN) and 2,4-dichlorophenoxyacetic acid (2,4-D) decreased TCA-2-14C absorption by wheat more than that by oats. From 5 to 21 days after application, wheat retained two to four times as much TCA-2-14C as oats. Thus, half of the TCA-2-14C in shoots and roots of wheat disappeared in 11.3 and 11.4 days, respectively, compared with 7.9 and 3.5 days for oats. Based on this investigation, the difference in susceptibility of wheat and oats to TCA appeared to be governed by the metabolic processes involved in absorption and dissipation.

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