scholarly journals Silicon-induced changes in plant volatiles reduce attractiveness of wheat to the bird cherry-oat aphid Rhopalosiphum padi and attract the parasitoid Lysiphlebus testaceipes

PLoS ONE ◽  
2020 ◽  
Vol 15 (4) ◽  
pp. e0231005
Author(s):  
Reinaldo Silva de Oliveira ◽  
Maria Fernanda G. V. Peñaflor ◽  
Felipe G. Gonçalves ◽  
Marcus Vinicius Sampaio ◽  
Ana Paula Korndörfer ◽  
...  
Keyword(s):  
Plant Volatiles ◽  
Rhopalosiphum Padi ◽  
Lysiphlebus Testaceipes ◽  
Induced Changes

scholarly journals Plantas refugio: su rol en el control biológico de Myzus persicae Sulzer (Hemiptera: Aphididae) en el cultivo de duraznero Prunus persica (L.) Batsch (Rosaceae) en Junín, Mendoza, Argentina

2017 ◽  
Author(s):  
◽  
María Emilia Mazzitelli
Keyword(s):  
Avena Sativa ◽  
Myzus Persicae ◽  
Prunus Persica ◽  
Rhopalosiphum Padi ◽  
Aphis Gossypii ◽  
Lysiphlebus Testaceipes ◽  
Aphidius Colemani ◽  
Aphis Gossypii Glover ◽  
Para Determinar

El control de Myzus persicae Sulzer (Hemiptera: Aphididae) en la producción de duraznero, se lleva a cabo principalmente mediante el uso de insecticidas, cuyo uso indiscriminado puede causar diferentes efectos adversos en los agroecosistemas. Esta investigación presentó como objetivo principal: evaluar el empleo del sistema de Avena sativa-Rhopalosiphum padi-Aphidius colemani, como estrategia para el control biológico de M. persicae en el cultivo de P. persica por medio de la técnica de plantas refugio o banker plants. En una parcela comercial de duraznero en Junín (Prov. de Mendoza, Argentina), se realizaron muestreos para determinar las asociaciones planta-áfido-parasitoide en la vegetación aledaña al cultivo, en gramíneas del interfilar y en el monte frutal. En la vegetación aledaña, se relevaron 16 especies vegetales en las que se identificaron 13 especies de áfidos y siete especies de parasitoides primarios. El áfido dominante fue Aphis gossypii Glover mientras que Lysiphlebus testaceipes (Cresson) fue el parasitoide dominante. En relación a las gramíneas, se encontraron cinco especies de áfidos y seis de parasitoides primarios, Ropalosiphum maidis (Fitch) fue el áfido dominante y A. colemani el parasitoide dominante. En duraznero, la asociación M. persicae-A. colemani fue la más importante. Se evaluaron a campo tres estrategias de control: Insecticida (Imidacloprid 70% WP), Testigo y liberación de A. colemani a razón de 2 Momias/m2. El parasitoidismo natural aumentó mas del 30% en el segundo año de estudio registrando el testigo la mayor proporción de parasitoides secundarios. El tratamiento 2 Momias/m2 presentó, tasas superiores y un crecimiento más rápido del parasitoidismo de M. persicae respecto a los otros, revelando además valores similares al tratamiento con insecticida en relación al daño producido por M. persicae. La diversidad de parasitoides primarios medida por el Índice de Shannon-Wiener fue de 2,0452 para el tratamiento 2 Momias/m2, de 1,7824 para el Testigo y de 1,7201 para el Insecticida. El control biológico por medio del uso de plantas refugio se considera una alternativa viable para el control de la plaga M. persicae.

scholarly journals Occurrence and parasitism of aphids (Hemiptera: Aphididae) on cultivars of irrigated oat (Avena spp.) in São Carlos, Brazil

2004 ◽  
Vol 47 (2) ◽  
pp. 163-169 ◽  
Author(s):  
Júlio Cesar Ronquim ◽  
Josué Marques Pacheco ◽  
Carlos Cesar Ronquim
Keyword(s):  
Rhopalosiphum Padi ◽  
The Other ◽  
Diaeretiella Rapae ◽  
Lysiphlebus Testaceipes ◽  
Aphidius Colemani ◽  
Parasitic Hymenoptera ◽  
Parasitism Rates ◽  
Hymenopteran Parasitoids

The interactions between aphids and their Hymenopteran parasitoids on irrigated oats as well as the response of different cultivars of cereals regarding the resistance to these aphids and the influence on the host/parasitoid relationships were studied during two years in São Carlos, Brazil. Rhopalosiphum padi (L.) was the predominant aphid observed throughout the study, while the other species were rarely found. Five species of parasitic Hymenoptera were found: three primary parasitoids, Lysiphlebus testaceipes (Cresson), Aphidius colemani (Viereck) and Diaeretiella rapae (M'Intosh) and two hyperparasitoids, Syrphophagus aphidivorus (Myer) and Alloxysta brassicae (Ashmead). The UPF 86081 cultivar presented significant results regarding lower Rhopalosiphum padi contamination and higher aphid parasitism rates than those observed on some other cultivars. No significant effect on the percentage variation of parasitoid emergence on the mummified aphids was observed throughout this study.

Interpretation of irradiation-induced changes in electron diffractograms and images of extinction contours at low temperatures

1984 ◽  
Vol 42 ◽  
pp. 268-269
Author(s):  
E. Knapek ◽  
H. Formanek ◽  
G. Lefranc ◽  
I. Dietrich
Keyword(s):  
Low Temperatures ◽  
Carbon Films ◽  
Organic Crystals ◽  
Wide Spread ◽  
Lens System ◽  
Preparation Conditions ◽  
Thin Carbon ◽  
Electron Diffractograms ◽  
Diffraction Patterns ◽  
Induced Changes

A few years ago results on cryoprotection of L-valine were reported, where the values of the critical fluence De i.e, the electron exposure which decreases the intensity of the diffraction reflections by a factor e, amounted to the order of 2000 + 1000 e/nm2. In the meantime a discrepancy arose, since several groups published De values between 100 e/nm2 and 1200 e/nm2 /1 - 4/. This disagreement and particularly the wide spread of the results induced us to investigate more thoroughly the behaviour of organic crystals at very low temperatures during electron irradiation.For this purpose large L-valine crystals with homogenuous thickness were deposited on holey carbon films, thin carbon films or Au-coated holey carbon films. These specimens were cooled down to nearly liquid helium temperature in an electron microscope with a superconducting lens system and irradiated with 200 keU-electrons. The progress of radiation damage under different preparation conditions has been observed with series of electron diffraction patterns and direct images of extinction contours.

Drug Induced Changes in Cell Organelles

1968 ◽  
Vol 26 ◽  
pp. 110-111
Author(s):  
Sarah A. Luse
Keyword(s):  
Clinical Medicine ◽  
Cell Organelles ◽  
Riboflavin Deficiency ◽  
Drug Induced ◽  
New Era ◽  
Health And Disease ◽  
In The Beginning ◽  
Cellular Pathology ◽  
Induced Changes ◽  
The Impact

In the mid-nineteenth century Virchow revolutionized pathology by introduction of the concept of “cellular pathology”. Today, a century later, this term has increasing significance in health and disease. We now are in the beginning of a new era in pathology, one which might well be termed “organelle pathology” or “subcellular pathology”. The impact of lysosomal diseases on clinical medicine exemplifies this role of pathology of organelles in elucidation of disease today.Another aspect of cell organelles of prime importance is their pathologic alteration by drugs, toxins, hormones and malnutrition. The sensitivity of cell organelles to minute alterations in their environment offers an accurate evaluation of the site of action of drugs in the study of both function and toxicity. Examples of mitochondrial lesions include the effect of DDD on the adrenal cortex, riboflavin deficiency on liver cells, elevated blood ammonia on the neuron and some 8-aminoquinolines on myocardium.

Digital x-ray mapping of nanometer-size supported bimetallic catalysts

1988 ◽  
Vol 46 ◽  
pp. 530-531
Author(s):  
L. T. Germinario
Keyword(s):  
Background Radiation ◽  
Metal Cluster ◽  
Single Element ◽  
Beam Diameter ◽  
X Rays ◽  
X Ray ◽  
Major Interest ◽  
Induced Changes

Understanding the role of metal cluster composition in determining catalytic selectivity and activity is of major interest in heterogeneous catalysis. The electron microscope is well established as a powerful tool for ultrastructural and compositional characterization of support and catalyst. Because the spatial resolution of x-ray microanalysis is defined by the smallest beam diameter into which the required number of electrons can be focused, the dedicated STEM with FEG is the instrument of choice. The main sources of errors in energy dispersive x-ray analysis (EDS) are: (1) beam-induced changes in specimen composition, (2) specimen drift, (3) instrumental factors which produce background radiation, and (4) basic statistical limitations which result in the detection of a finite number of x-ray photons. Digital beam techniques have been described for supported single-element metal clusters with spatial resolutions of about 10 nm. However, the detection of spurious characteristic x-rays away from catalyst particles produced images requiring several image processing steps.

Immunogold localization of calmodulin in root caps of the maize Cultivar Merit

1990 ◽  
Vol 48 (3) ◽  
pp. 674-675
Author(s):  
P.T. Nguyen ◽  
C. Uphoff ◽  
C.L. Stinemetz
Keyword(s):  
Calcium Binding ◽  
Calcium Transport ◽  
Primary Role ◽  
Immunogold Localization ◽  
Root Tips ◽  
Electrical Currents ◽  
Considerable Evidence ◽  
Maize Cultivar ◽  
Gravity Response ◽  
Induced Changes

Considerable evidence suggest that the calcium-binding protein calmodulin (CaM) may mediate calcium action and/or transport important in the gravity response of plants. Calmodulin is present in both shoots and roots and is capable of regulating calcium transport in plant vesicles. In roots calmodulin is concentrated in the tip, the gravisensing region of the root; and is reported to be closely associated with amyloplasts, organelles suggested to play a primary role in gravi-perception. Inhibitors of CaM such as chlorpromazine, calmidazolium, and compound 48/80 interfere with the gravitropic response of both snoots and roots. The magnitude of the inhibition corresponded well with the extent to which the drug binds to endogenous CaM. Compound 48/80 and calmidazolium block gravi-induced changes in electrical currents across root tips, a phenomenon thought to be associated with the sensing of the gravity stimulus.In this study, we have investigated the subcellular distribution of CaM in graviresponsive and non-graviresponsive root caps of the maize cultivar Merit.

Identifying groups of airborne particles by ordination

1994 ◽  
Vol 52 ◽  
pp. 856-857
Author(s):  
M. Shlepr ◽  
C. M. Vicroy
Keyword(s):  
Elemental Analysis ◽  
Energy Dispersive Spectroscopy ◽  
Manufacturing Process ◽  
Spatial Representation ◽  
Airborne Particles ◽  
Common Source ◽  
Data Set ◽  
Microelectronics Industry ◽  
Induced Changes ◽  
Source Materials

The microelectronics industry is heavily tasked with minimizing contaminates at all steps of the manufacturing process. Particles are generated by physical and/or chemical fragmentation from a mothersource. The tools and macrovolumes of chemicals used for processing, the environment surrounding the process, and the circuits themselves are all potential particle sources. A first step in eliminating these contaminants is to identify their source. Elemental analysis of the particles often proves useful toward this goal, and energy dispersive spectroscopy (EDS) is a commonly used technique. However, the large variety of source materials and process induced changes in the particles often make it difficult to discern if the particles are from a common source.Ordination is commonly used in ecology to understand community relationships. This technique usespair-wise measures of similarity. Separation of the data set is based on discrimination functions. Theend product is a spatial representation of the data with the distance between points equaling the degree of dissimilarity.

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