scholarly journals Apple, Insecticide DIP Test (Tabm vs. Insecticides), 1993

1994 ◽  
Vol 19 (1) ◽  
pp. 369-369
Author(s):  
R. L. Horsburgh ◽  
J. R. Warren
Keyword(s):  
Filter Paper ◽  
Room Temperature ◽  
Petri Dish ◽  
Spray Application ◽  
Water Control ◽  
Poor Control ◽  
Laboratory Bioassay ◽  
The Third ◽  
Petri Dishes ◽  
Dip Test

Abstract A large commercial apple grower reported failure in attempts to control TABM with airblast applications of Penncap M (2 pt/acre) combined with methomyl (3 pt/acre). At the time of the grower applications larval hatch had begun and most larvae were in the first or second instar. By the time larvae were entering the third instar (10 days after spray application) it was apparent that commercially acceptable control had not been achieved. In 1992 this grower also had poor control when Penncap M was applied to suppress redbanded leafroller and experiments showed that tolerance of Penncap M was present in the resident RBLR population (Horsburgh et al. 1992). This laboratory bioassay was begun on 3 Sep to determine tolerance of the TABM population to Penncap M and other insecticides. Seven treatments (including a water control) were selected and rates calculated on the basis of 300 gal of spray being applied per acre. The appropriate dosage of pesticide for each treatment was mixed with 1 gallon of 77°F water in clean 1 gallon battery jars. Twenty plastic petri dishes containing moistened filter paper were prepared and served as individual cages for twenty 3rd instars per treatment. The larvae, on single leaves, were immersed in the appropriate solutions for five seconds and the leaf placed on the moist filter paper. The petri dish cover was put in place and the cages held at room temperature (80°F) for the duration of the test. All larvae were examined at 24 hour intervals and mortality was recorded. Death of larvae was assumed when no movement was observed when the larvae were gently prodded with a blunt steel probe.

scholarly journals Laboratory Bioassay of Beauveria Bassiana, Spinosad, Garlic, and Neem-Derived Products for Control of Grasshoppers

1998 ◽  
Vol 23 (1) ◽  
pp. 372-372
Author(s):  
Nihat Demirel ◽  
Whitney Cranshaw
Keyword(s):  
Beauveria Bassiana ◽  
Petri Dish ◽  
Neem Oil ◽  
Laboratory Bioassay ◽  
Neem Extract ◽  
Late Instar ◽  
Petri Dishes

Abstract Trials were conducted with adult, field collected migratory grasshoppers to determine susceptibility to ingestion expo sure to Beauveria bassiana Strain GHA (BotaniGard WP), spinosad (Conserve SC) a garlic-derived insecticide/repellent (Garlic Barrier), neem oil (Tril ogy) and a neem extract (BioNeem). Field collected late instar grasshoppers were confined, 8 per petri dish (100 mm X 15 mm), with 6 petri dishes usetl per treatment. Treatments involved dipping alfalfa leaves into the insecticide solutions and allowing them to air dry before feeding these to the grasshop pers. After the originally treated foliage were consumed, untreated foliage was used to maintain grasshoppers in all treatments. Mortality was assessed a 24, 48, 96, and 192 h after exposure.

scholarly journals Toxicity of Three Formulations of Bacillus Thuringiensis Against Diamondback Moth, 1996

1998 ◽  
Vol 23 (1) ◽  
pp. 369-369
Author(s):  
P. W. Ivey ◽  
S. J. Johnson ◽  
Richard Story
Keyword(s):  
Bacillus Thuringiensis ◽  
Untreated Control ◽  
Room Temperature ◽  
Diamondback Moth ◽  
Petri Dish ◽  
Test Solution ◽  
Leaf Disk ◽  
Distilled Water ◽  
Dilution Series ◽  
Petri Dishes

Abstract A leaf-dip assay was used to test three commercial formulations of B. thuringiensis Berliner: Agree 50 WP, Dipel ES, and XenTari AS, against diamondback moth. Concentrations ([AI]/liter) were based on dilution series using the recommended “field” rates of the three formulations of B. thuringiensis. Dipel and Xen-Tari were tested at concentrations of 2.5, 0.25, 0.025, 0.0025, and 0.00025 [ml (AI)/liter]; Agree was tested at concentrations of 3.0, 0.3, 0.03, 0.003, and 0.0003 [g(AI)/liter]. Disks (20 mm diam) were cut from leaves of the above cabbage cultivar. Each disk was dipped into each test solution and hung vertically to dry at room temperature for about 1 h and then placed in petri dishes (100 X 15 mm) on top of a moistened filter peper (90 mm diameter). Five third instars were placed on each leaf disk in each petri dish and allowed to feed for 96 h, after which mortality was recorded. A larva was considered dead if it did not move when prodded with forceps. Tests with each concentration and the untreated control (distilled water) were replicated five times.

scholarly journals Laboratory Bioassay of Beauveria Bassiana and Spinosad for Control of Grasshoppers

1998 ◽  
Vol 23 (1) ◽  
pp. 372-372
Author(s):  
Nihat Demirel ◽  
Whitney Cranshaw
Keyword(s):  
Beauveria Bassiana ◽  
Petri Dish ◽  
Laboratory Bioassay ◽  
Petri Dishes ◽  
Test Materials ◽  
Serial Dilutions

Abstract Trials were con ducted with adult, field collected migratory grasshoppers to determine susceptibility to ingestion exposure to Beauveria bassiana Strain GHA (BotaniGard WP) or spinosad (Conserve SC). Grasshoppers were confined, 8 per petri dish, with 5 petri dishes used per treatment. Alfalfa was dipped in serial dilutions (0.25X) of the test materials, allowed to air dry and then placed with grasshoppers. After the originally treated foliage was consumed, untreated foliage was used to maintain grasshoppers in all treatments. Mortality was assessed at 24 hour intervals for six days following exposure.

SEM Observations on the Germination of Euonymous Americanus

1985 ◽  
Vol 43 ◽  
pp. 508-509
Author(s):  
D.R. Hill ◽  
J.R. McCurry ◽  
L.P. Elliott ◽  
G. Howard
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Light Microscopy ◽  
Filter Paper ◽  
Room Temperature ◽  
Food Source ◽  
Environmental Chamber ◽  
Dormant Stage ◽  
Scanning Electron

Germination of Euonymous americanus in the laboratory has previously been unsuccessful. Ability to germinate Euonymous americanus. commonly known as the american strawberry bush, is important in that it represents a valuable food source for the white-tailed deer. Utilizing the knowledge that its seeds spend a period of time in the rumin fluid of deer during their dormant stage, we were successful in initiating germination. After a three month drying period, the seeds were placed in 25 ml of buffered rumin fluid, pH 8 at 40°C for 48 hrs anaerobically. They were then allowed to dry at room temperature for 24 hrs, placed on moistened filter paper and enclosed within an environmental chamber. Approximately four weeks later germination was detected and verified by scanning electron microscopy; light microscopy provided inadequate resolution. An important point to note in this procedure is that scarification, which was thought to be vital for germination, proved to be unnecessary for successful germination to occur. It is believed that germination was propagated by the secretion of enzymes or prescence of acids produced by microorganisms found in the rumin fluid since sterilized rumin failed to bring about germination.

A freeze-fracture-etched study of the physarum polycephalum plasma membrane during early formation of the macroplasmodial stage

1993 ◽  
Vol 51 ◽  
pp. 346-347
Author(s):  
Randolph W. Taylor ◽  
Henrie Treadwell
Keyword(s):  
Plasma Membrane ◽  
Life Cycle ◽  
Growth Phase ◽  
Filter Paper ◽  
Physarum Polycephalum ◽  
Freeze Fracture ◽  
Petri Dish ◽  
Wire Screen ◽  
Wide Mouth ◽  
Sterile Filter

The plasma membrane of the Slime Mold, Physarum polycephalum, process unique morphological distinctions at different stages of the life cycle. Investigations of the plasma membrane of P. polycephalum, particularly, the arrangements of the intramembranous particles has provided useful information concerning possible changes occurring in higher organisms. In this report Freeze-fracture-etched techniques were used to investigate 3 hours post-fusion of the macroplasmodia stage of the P. polycephalum plasma membrane.Microplasmodia of Physarum polycephalum (M3C), axenically maintained, were collected in mid-expotential growth phase by centrifugation. Aliquots of microplasmodia were spread in 3 cm circles with a wide mouth pipette onto sterile filter paper which was supported on a wire screen contained in a petri dish. The cells were starved for 2 hrs at 24°C. After starvation, the cells were feed semidefined medium supplemented with hemin and incubated at 24°C. Three hours after incubation, samples were collected randomly from the petri plates, placed in plancettes and frozen with a propane-nitrogen jet freezer.

Cholesterol in Serum and Lipoprotein Fractions

1956 ◽  
Vol 2 (3) ◽  
pp. 145-159 ◽  
Author(s):  
Joseph T Anderson ◽  
Ancel Keys
Keyword(s):  
Human Serum ◽  
Total Cholesterol ◽  
Filter Paper ◽  
Room Temperature ◽  
Paper Electrophoresis ◽  
Cholesterol Content ◽  
Intraindividual Variability ◽  
Detailed Data ◽  
The Stability ◽  
Source Of Error

Abstract 1. Methods are described for the separation, by paper electrophoresis and by cold ethanol, of α- and β-lipoproteins in 0.1 ml. of serum, with subsequent analysis of cholesterol in the separated portions. 2. It is shown that both methods of separation yield separated fractions containing substantially the same amounts of cholesterol. 3. Detailed data are given on the errors of measurement for total cholesterol and for cholesterol in the separated lipoprotein fractions. 4. Studies are reported on the stability of cholesterol in stored serum and on paper electrophoresis strips. It is shown that simple drying on filter paper causes no change in cholesterol content and yields a product that is stable for many weeks at ordinary room temperature. 5. The sources of variability in human serum cholesterol values are examined and it is shown that spontaneous intraindividual variability is a much greater source of error than the errors of measurement with these methods.

scholarly journals Response of Mexican Corn Rootworm to Insecticides, 1991

1995 ◽  
Vol 20 (1) ◽  
pp. 329-329
Author(s):  
E. Guerrero-Rodriguez ◽  
S. Davalos-Luna ◽  
J. Corrales-Reynaga
Keyword(s):  
Petri Dish ◽  
Mortality Data ◽  
Corn Rootworm ◽  
Field Corn ◽  
Paper Towel ◽  
Percent Mortality ◽  
Petri Dishes ◽  
Mexican Corn Rootworm ◽  
Corn Plants ◽  
Commercial Field

Abstract Populations of MCR of commercial field corn from Arenal, Jalisco were exposed to nine insecticides of organophosphorous (OP), cabamate, organo chlorinated and pyrethroid groups. Larvae were collected from the roots of corn plants daily, and confined in polyethylene black bags of two kg capacity with humidity and germinated corn as food for larvae. Insects were taken to the laboratory of Sanidad Vegetal in Guadalajara, Jalisco. Dilutions of the insecticides tested were prepared using acetone from 500 to 5000 ppm (6 to 9 dosage/product). For this study 20 larvae of last instar were selected and 1 u, liter of the solution was placed topically on the thorax, after this, each larva was placed in a petri dish with a moistened paper towel and the petri dishes confined in a cardboard box to eliminate light. Mortality counts were carried out at 24 hours. Percent mortality was corrected by Abbott’s formula. The mortality data were analyzed by probit to obtain LC50 and LC,5 values for each insecticide.

Crystal Structures of and Polarized Absorption-Spectroscopy in Racemic and Resolved [Ru(bpy)3] (ClO4)2 and [Zn(bpy)3] (ClO4)2Bpy=2,2'-Bipyridine

1995 ◽  
Vol 48 (5) ◽  
pp. 929 ◽  
Author(s):  
E Krausz ◽  
H Riesen ◽  
AD Rae
Keyword(s):  
Room Temperature ◽  
Energy Difference ◽  
Temperature Structure ◽  
Asymmetric Unit ◽  
Threefold Axis ◽  
Crystal Forms ◽  
The Third ◽  
Racemic Form ◽  
Ligand Charge Transfer ◽  
Dominant Influence

[Zn( bpy )3] (ClO4)2 and [ Ru ( bpy )3] (ClO4)2 are isomorphous in both their racemic and resolved crystal forms. The resolved materials are monohydrates and have a C 2, Z = 8, structure with two independent formula units on general sites in the asymmetric unit. The cations have the same chirality. The inherent threefold axis of each cation lies approximately parallel to the c axis. The unrelated racemic form has a C2/c, Z = 4, structure which is a commensurate modulation of a P3c1, Z = 2, parent structure, typified by the room-temperature structure of [ Ru ( bpy )3] (PF6)2. A primary, secondary and tertiary axis of P3c1 become the c, b and a axes respectively of C2/c, retaining a third of the symmetry elements of P3c1. The crystals grow as multiply contacted twins. This structure bas just one spectroscopic site with the cation lying on a twofold axis that passes through the metal and one of the bidendate ligands and relates the other two ligands to each other. This feature is particularly useful in the study of the optical spectroscopy of the metal-to- ligand charge transfer excitations of [ Ru ( bpy )3]2+ and related systems. A comparison of structural and spectral data indicates that the positions of the anions have a dominant influence on the relative energies of the metal-to- ligand excitations. An energy difference between excitations involving the two (lower-energy) equivalent ligands and the third ligand of the order of 800 cm-1 is indicated in both singlet and triplet regions for the racemic perchlorate. The absorption spectra of [ Ru ( bpy )3]2+and [Os( bpy )3]2+ in a number of crystalline hosts are compared and discussed.

The prediction of the cyclic mechanical behavior of stainless steel 304L at room temperature

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Hala Messai ◽  
Salim Meziani ◽  
Athmane Fouathia
Keyword(s):  
Stainless Steel ◽  
Design Methodology ◽  
Room Temperature ◽  
Type Model ◽  
Good Prediction ◽  
304L Stainless Steel ◽  
Content Type ◽  
The Third ◽  
Chaboche Model

Purpose The purpose of this paper is to highlight the performance of the Chaboche model in relation to the database identification, tests with imposed deformations were conducted at room temperature on 304L stainless steel specimens. Design/methodology/approach The first two tests were performed in tension-compression between ±0.005 and ±0.01; in the third test, each cycle is composed of the combination of a compression tensile cycle between ±0.01 followed by a torsion cycle between ±0.01723 (non-proportional path), and the last, uniaxial ratcheting test with a mean stress between 250 MPa and −150 MPa. Several identifications of a Chaboche-type model were then performed by considering databases composed of one or more of the cited tests. On the basis of these identifications, the simulations of a large number of ratchet tests in particular were carried out. Findings The results present the effect of the optimized parameters on the prediction of the behavior of materials which is reported in the graphs, Optimizations 1 and 2 of first and second tests and Optimization 4 of the third test giving a good prediction of the increasing/decreasing pre-deformation amplitude. Originality/value The quality of the model's predictions strongly depends on the richness of the database used for the identification of the parameters.

scholarly journals SEED PRODUCTIVITY AND DEVELOPMENT OF PLANTLETS POPULUS × JRTYSCHENSIS CH. Y. YANG

2019 ◽  
pp. 51-57
Author(s):  
B. V. Proshkin ◽  
A. V. Klimov
Keyword(s):  
Filter Paper ◽  
Fruit Set ◽  
Control Group ◽  
Natural Hybrid ◽  
Seed Productivity ◽  
Model Trees ◽  
Fruit Number ◽  
Black Poplar ◽  
Petri Dishes ◽  
Number Of Seeds

The research explores the seed productivity and plantlets growth in the free pollination of the natural hybrid taxon P. × jrtyschensis. Fruits of P. × jrtyschensis were selected from four plants that grow in the collection ofResearchCenter“EducationalBotanical Garden” ofKemerovoStateUniversity. Four P. nigra model trees, randomly selected from theTomRiverfloodplain population, were applied as a control group. The authors used 30 fruit-bearing amentumsfrom each model. The researchers measured set of fruit (capsule); number of ovules per fruit; number of seeds per fruit; set of seeds.. Laboratory germination was determined by sowing Petri dishes on wet filter paper. The authors found out sowing germination by sowing 100 seeds in a box with soil and drainage. The energy of germination was determined on the second day while germination - on the fifth day. P. × jrtyschensis is characterized by a lower level of seed productivity (15-30%) compared to P. nigra. In terms of laboratory germination of seeds, the descendants of hybrids surpassed many P. nigra models, but their soil germination was 20-30% lower than that of black poplar. The observed variability in reproductive indices of both P. × jrtyschensis and P. nigra is mainly caused by specific features of their genotypes. Plantlets being developed, the authors observed no significant differences among the descendants of P. nigra and hybrids. The researchers highlighted plantlets that can stop growing and even more abnormal plants with one, three or four seeds in P. × jrtyschensis. This may be caused by underdevelopment of hypocotyl or germ root. The authors observed breaches in development of P. nigra just once. They outline high plantlets destruction when sowing hybrids on the first day after germination The share of destructed plants within a month (from the beginning of the experiment) reaches 66,0 %, and in P. nigra it does not exceed 40,0 %.

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