Variations in acaricidal effect of wettable sulfur onTetranychus urticae (Acari: Tetranychidae): effect of temperature, humidity and life stage

The study of the transmission biology of insect-borne plant viruses is important to develop disease control practices. We characterized the transmission of a nanovirus, Banana bunchy top virus (BBTV), by its aphid vector Pentalonia nigronervosa Coquerel (Hemiptera, Aphididae) with respect to temperature, vector life stage, and plant access time. Adult aphids transmitted BBTV more efficiently than third instar nymphs at all temperatures tested. Adult aphids transmitted the virus more efficiently at 25 and 30°C than at 20°C, but temperature had no impact on transmission efficiency by nymphs. By decoupling the relationship between temperature and aphid BBTV acquisition or inoculation, we determined that temperature affected inoculation events more strongly than acquisition. Longer plant access periods increased viral acquisition and inoculation efficiencies in a range of 60 min to 24 h. Both BBTV acquisition and inoculation efficiencies peaked after 18 h of plant access period. We also show that BBTV transmission by P. nigronervosa requires a latent period. Our results demonstrate that vector transmission of BBTV is affected by temperature, vector life stage, and plant access period.

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TEMPERATURE-DEPENDENT DEVELOPMENT OF THE MOUNTAIN PINE BEETLE (COLEOPTERA: SCOLYTIDAE) AND SIMULATION OF ITS PHENOLOGY

The Canadian Entomologist ◽

10.4039/ent1231083-5 ◽

1991 ◽

Vol 123 (5) ◽

pp. 1083-1094 ◽

Cited By ~ 156

Author(s):

Barbara J. Bentz ◽

Jesse A. Logan ◽

Gene D. Amman

Keyword(s):

Mountain Pine Beetle ◽

Lodgepole Pine ◽

Life Stage ◽

Temporal Distribution ◽

Effect Of Temperature ◽

Life Stages ◽

Temperature Dependent ◽

Dependent Development ◽

Mountain Pine ◽

Pine Beetle

AbstractTemperature-dependent development of the egg, larval, and pupal life-stages of the mountain pine beetle (Dendroctonus ponderosae Hopkins) was described using data from constant-temperature laboratory experiments. A phenology model describing the effect of temperature on the temporal distribution of the life-stages was developed using these data. Phloem temperatures recorded in a beetle-infested lodgepole pine (Pinus contorta Douglas) were used as input to run the model. Results from model simulations suggest that inherent temperature thresholds in each life-stage help to synchronize population dynamics with seasonal climatic changes. This basic phenological information and the developed model will facilitate both research and management endeavors aimed at reducing losses in lodgepole pine stands caused by mountain pine beetle infestations.

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Effect of Temperature and Host Life Stage on Efficacy of Soil Entomopathogens Against the Swede Midge (Diptera: Cecidomyiidae)

Journal of Economic Entomology ◽

10.1093/jee/tov050 ◽

2015 ◽

Vol 108 (2) ◽

pp. 473-483 ◽

Cited By ~ 4

Author(s):

B. G. Evans ◽

K. S. Jordan ◽

M. Brownbridge ◽

R. H. Hallett

Keyword(s):

Life Stage ◽

Effect Of Temperature ◽

Swede Midge ◽

Host Life

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Influence of Temperature on Development and Reproduction of Ditylenchus weischeri and D. dipsaci on Yellow Pea

Plant Disease ◽

10.1094/pdis-04-16-0479-re ◽

2017 ◽

Vol 101 (2) ◽

pp. 297-305 ◽

Cited By ~ 4

Author(s):

Abolfazl Hajihassani ◽

Mario Tenuta ◽

Robert H. Gulden

Keyword(s):

Generation Time ◽

Life Stage ◽

Nematode Species ◽

Positive Control ◽

Effect Of Temperature ◽

Growing Degree Days ◽

Degree Days ◽

Canadian Prairies ◽

Stage Progression ◽

Air Temperatures

The ability of the recently described stem nematode of creeping thistle (Cirsium arvense L.), Ditylenchus weischeri, to develop on and parasitize yellow pea (Pisum sativum L.) is uncertain. The current study examined nematode life-stage progression and generation time on yellow pea as affected by temperature with the related pest, D. dipsaci, used as a positive control. Relationships for body length of the two nematode species and life stage were unaffected by rearing on plant hosts compared with carrot disks. Then plant-reared J4 individuals of both nematode species were used to determine the effect of temperature (17, 22, and 27°C) on life-stage progression and minimum generation time with yellow pea. At 17 and 22°C, D. weischeri J4 individuals progressed to only the adult stage whereas, at 27°C, the minimum generation time from J4 to J4 was 30 days or 720 growing degree-days. The minimum generation time for D. dipsaci was 24, 18, and 22 days or 336, 342, and 528 growing degree-days at 17, 22, and 27°C, respectively. The results indicate that development of D. weischeri is temperature dependent and reproduction is unlikely on yellow pea in the Canadian Prairies, where mean daily air temperatures of 27°C are rare and not sustained.

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Nucleation of Disorder in Fe3Al Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100061574 ◽

1967 ◽

Vol 25 ◽

pp. 312-313

Author(s):

P. R. Swann ◽

W. R. Duff ◽

R. M. Fisher

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Annealing Temperature ◽

Antiphase Domain ◽

Effect Of Temperature ◽

Domain Structures ◽

Transmission Electron ◽

Domain Boundaries ◽

Higher Temperature ◽

The One

Recently we have investigated the phase equilibria and antiphase domain structures of Fe-Al alloys containing from 18 to 50 at.% Al by transmission electron microscopy and Mössbauer techniques. This study has revealed that none of the published phase diagrams are correct, although the one proposed by Rimlinger agrees most closely with our results to be published separately. In this paper observations by transmission electron microscopy relating to the nucleation of disorder in Fe-24% Al will be described. Figure 1 shows the structure after heating this alloy to 776.6°C and quenching. The white areas are B2 micro-domains corresponding to regions of disorder which form at the annealing temperature and re-order during the quench. By examining specimens heated in a temperature gradient of 2°C/cm it is possible to determine the effect of temperature on the disordering reaction very precisely. It was found that disorder begins at existing antiphase domain boundaries but that at a slightly higher temperature (1°C) it also occurs by homogeneous nucleation within the domains. A small (∼ .01°C) further increase in temperature caused these micro-domains to completely fill the specimen.

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The effect of temperature on high-resolution TEM image contrast

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100139573 ◽

1995 ◽

Vol 53 ◽

pp. 640-641

Author(s):

T. Geipel ◽

W. Mader ◽

P. Pirouz

Keyword(s):

Form Factor ◽

Inelastic Scattering ◽

Accurate Method ◽

Waller Factor ◽

Effect Of Temperature ◽

Specimen Thickness ◽

Influence Of Temperature ◽

Debye Waller Factor ◽

Influence Of Temperature On ◽

Atomic Form Factor

Temperature affects both elastic and inelastic scattering of electrons in a crystal. The Debye-Waller factor, B, describes the influence of temperature on the elastic scattering of electrons, whereas the imaginary part of the (complex) atomic form factor, fc = fr + ifi, describes the influence of temperature on the inelastic scattering of electrons (i.e. absorption). In HRTEM simulations, two possible ways to include absorption are: (i) an approximate method in which absorption is described by a phenomenological constant, μ, i.e. fi; - μfr, with the real part of the atomic form factor, fr, obtained from Hartree-Fock calculations, (ii) a more accurate method in which the absorptive components, fi of the atomic form factor are explicitly calculated. In this contribution, the inclusion of both the Debye-Waller factor and absorption on HRTEM images of a (Oll)-oriented GaAs crystal are presented (using the EMS software.Fig. 1 shows the the amplitudes and phases of the dominant 111 beams as a function of the specimen thickness, t, for the cases when μ = 0 (i.e. no absorption, solid line) and μ = 0.1 (with absorption, dashed line).

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