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1.
J Econ Entomol ; 111(2): 612-619, 2018 04 02.
Article in English | MEDLINE | ID: mdl-29514245

ABSTRACT

The khapra beetle, Trogoderma granarium Everts (Coleoptera: Dermestidae), is a serious pest of stored products and is the only stored product insect pest that triggers a quarantine response when it is found in the United States. The larvae of T. granarium feed on a wide range of dry food products of plant and animal origin, including cereals, dried fish, and museum specimens. In this study, we evaluated the residual efficacy of two pyrethroid insecticides, deltamethrin and cyfluthrin, applied on concrete, wood, painted wood, vinyl flooring tile, and metal surfaces using small and large T. granarium larvae. Residual efficacy of two insect growth regulators (IGRs), methoprene and pyriproxyfen was also evaluated on concrete, metal, and wood surfaces. In both studies, larvae were exposed with provision of a food source on the treated surfaces and residual assays were conducted at 0 months (1 d), 1, 2, and 3 months post treatment. In general, both of the pyrethroids provided a high level of control of T. granarium larvae, though small larvae were much more susceptible than large larvae. The IGRs were comparatively less effective, with more larval survival and adult emergence of exposed larvae compared with the pyrethroids. Residues of the pyrethroids and IGRs were most persistent on the metal surface. Results can be used to help to control and eradicate infestations of T. granarium when they are detected in the United States.


Subject(s)
Coleoptera , Insecticides , Juvenile Hormones , Pesticide Residues , Pyrethrins , Animals
2.
J Econ Entomol ; 109(1): 213-21, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26318005

ABSTRACT

Several North American walnut species (Juglans spp.) are threatened by thousand cankers disease which is caused by the walnut twig beetle (Pityophthorus juglandis Blackman) and its associated fungal plant pathogen, Geosmithia morbida M. Kolarík, E. Freeland, C. Utley and N. Tisserat sp. nov. Spread of this disease may occur via movement of infested black walnut (Juglans nigra L.) wood. This study evaluated the ability of P. juglandis to colonize J. nigra wood previously treated with various phytosanitation methods. Steam-heated and methyl bromide-fumigated J. nigra logs, as well as kiln-dried natural wane J. nigra lumber (with and without bark) were subsequently exposed to P. juglandis colonization pressure in two exposure scenarios. Following a pheromone-mediated, high-pressure scenario in the canopy of infested trees, beetles readily colonized the bark of steam-heated and methyl bromide-fumigated logs, and were also recovered from kiln-dried lumber on which a thin strip of bark was retained. In the simulated lumberyard exposure experiment, during which samples were exposed to lower P. juglandis populations, beetles were again recovered from bark-on steam-heated logs, but were not recovered from kiln-dried bark-on lumber. These data suggest logs and bark-on lumber treated with phytosanitation methods should not be subsequently exposed to P. juglandis populations. Further beetle exclusion efforts for phytosanitized, bark-on walnut wood products transported out of quarantined areas may be necessary to ensure that these products do not serve as a pathway for the spread of P. juglandis and thousand cankers disease.


Subject(s)
Insect Control/methods , Juglans/chemistry , Plant Diseases/prevention & control , Weevils/physiology , Wood/chemistry , Animals , Fumigation , Hot Temperature , Hydrocarbons, Brominated , Plant Bark/chemistry , Plant Diseases/microbiology , Population Dynamics , Steam , Weevils/microbiology
3.
J Econ Entomol ; 107(1): 174-84, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24665700

ABSTRACT

Thousand cankers disease, caused by the walnut twig beetle (Pityophthorus juglandis Blackman) and an associated fungal pathogen (Geosmithia morbida M. Kolarík, E. Freeland, C. Utley, and N. Tisserat), threatens the health and commercial use of eastern black walnut (Juglans nigra L.), one of the most economically valuable tree species in the United States. Effective phytosanitary measures are needed to reduce the possibility of spreading this insect and pathogen through wood movement. This study evaluated the efficacy of heat treatments and debarking to eliminate P. juglandis and C. morbida in J. nigra logs 4-18 cm in diameter and 30 cm in length. Infested logs were steam heated until various outer sapwood temperatures (60, 65, and 70 degrees C in 2011; 36, 42, 48, 52, and 56 degrees C in 2012) were maintained or exceeded for 30-40 min. In 2011, all heat treatments eliminated G. morbida from the bark, but logs were insufficiently colonized by P. juglandis to draw conclusions about treatment effects on the beetle. Debarking did not ensure elimination of the pathogen from the sapwood surface. In 2012, there was a negative effect of increasing temperature on P. juglandis emergence and G. morbida recovery. G. morbida did not survive in logs exposed to treatments in which minimum temperatures were 48 degrees C or higher, and mean P. juglandis emergence decreased steadily to zero as treatment minimum temperature increased from 36 to 52 degrees C. A minimum outer sapwood temperature of 56 degrees C maintained for 40 min is effective for eliminating the thousand cankers disease vector and pathogen from walnut logs, and the current heat treatment schedule for the emerald ash borer (60 degrees C core temperature for 60 min) is more than adequate for treating P. juglandis and G. morbida in walnut firewood.


Subject(s)
Coleoptera , Disinfection , Hot Temperature , Insect Vectors , Juglans/microbiology , Animals , Plant Diseases/microbiology
4.
Ophthalmology ; 93(12): 1604-11, 1986 Dec.
Article in English | MEDLINE | ID: mdl-3808619

ABSTRACT

Visual fields and dark-adapted thresholds, essential measurements of visual function in patients with retinitis pigmentosa (RP), are usually performed manually. The authors have modified a computerized perimeter to perform automated light- and dark-adapted static perimetry across the visual field of RP patients. Results permit assessment of the level of visual disability in the light and dark and also help define subtypes of RP.


Subject(s)
Adaptation, Physiological , Dark Adaptation , Light , Retinitis Pigmentosa/physiopathology , Visual Field Tests/methods , Adolescent , Adult , Automation , Child , Computers , Female , Humans , Male , Sensory Thresholds , Visual Field Tests/instrumentation
5.
Arch Ophthalmol ; 102(6): 870-5, 1984 Jun.
Article in English | MEDLINE | ID: mdl-6732567

ABSTRACT

A new automatic objective refractor was used on healthy adults. In the absence of cycloplegic drugs, spherocylindrical objective refractions performed with the instrument provided 20/20 acuity 96% as often as with standard subjective techniques. No instrument-induced accommodations effects were seen. One hundred percent of instrument spherical findings were repeatable within 0.50 diopters; all cylindrical findings were repeatable within 0.37 D. This result represents a higher level of repeatability than that reported for standard subjective refraction under clinical conditions. In the absence of cycloplegic drugs, the correlation coefficient between the instrument's findings and standard subjective spherical findings was .97 v .98 between two practitioners' subjective refractions. The average difference between cylindrical findings of the instrument and those of an experienced practitioner was 0.04 D larger than the average difference seen between two practitioners using subjective techniques.


Subject(s)
Ophthalmology/instrumentation , Refraction, Ocular , Accommodation, Ocular/drug effects , Adolescent , Adult , Automation , Evaluation Studies as Topic , Humans , Middle Aged , Mydriatics/pharmacology , Refractive Errors/diagnosis , Visual Acuity
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