Hair Brush Research Articles

Leaf-Dip Bioassays of Chitin Inhibitors and Abg-6178 for Control of Colorado Potato Beetle on Potatoes, 1991

Abstract All bioassays used larvae aged 36 ± 12 h from a laboratory strain of Colorado potato beetles reared on greenhouse-grown ‘Norland’ potatoes. The entomopathogen Beauveria bassiana (Balsamo) Vuillemin was assayed as both a technical powder (ABG-6178) and as aerial conidia grown in the laboratory. The fungus was cultured for 10 to 20 d on Sabouraud‘s dextrose agar after isolation from adult Colorado potato beetle cadavers previously infected with ABG-6178. Treatments were applied by submersing terminal potato leaflets (of about 10 cm2) for 4 s in a test concentration. A wetting agent, Tween 80 (0.05% concentration), was used to prepare all dilutions. Controls were treated with 0.05% Tween 80 alone. Treated leaves were allowed to drain on absorbent paper for about 60 s and placed into individual assay chambers to air dry. Four to five larvae were then placed on each treated leaf with a camel hair brush. Assays were repeated 2 to 4 times. Assay chambers were made of two stacked 60 x 20 mm plastic petri dishes. The top petri dish was lined with moist filter paper. A hole drilled through the dish base allowed the leaf petiole to extend into the lower petri dish which held a distilled water reservoir to maintain leaf turgor. Assays were kept in a growth chamber at 23°C, 70-80% RH and 18:6 L:D. Leaves were replaced after 48 h and, thereafter, as necessary. Mortality was counted at 24 h intervals after 3 to 7 d of exposure. Individuals not responding to tactile stimulation were considered dead. Data were corrected with Abbott‘s formula and analyzed using probit analysis (POLO-PC). Not all treatments were assayed on each day.

In Vitro Effects of Citric Acid Application Techniques on Dentin Surfaces

The present study evaluated the in vitro effects of different application techniques of citric acid on dentin root surfaces. Ten freshly extracted, periodontally involved teeth were obtained and 4 dentin slabs, approximately 4 x 6 x 2 mm, were obtained from the roots of each tooth, for a total of 40 slabs. These slabs were identified by tooth and preserved in 1:1 anhydrous glycerol/absolute alcohol solution. Citric acid pH 1 was applied to 32 of the slabs for 5 minutes with one of 4 different techniques: 1) immersion; 2) placed with a saturated cotton pellet with no rubbing; 3) placed and burnished with a saturated cotton pellet; or 4) applied with a camel hair brush. The remaining 8 dentin slabs were used as negative control specimens, root-planed and non-acid treated. Following the various treatments, the slabs were fixed, dehydrated, critical point dried, and coated for scanning electron microscopic (SEM) evaluation. Scanning photomicrographs were obtained at 2,000, 6,000, and 40,000 magnifications. The surface characteristics of the treated dentin slabs were evaluated descriptively regarding the degree of fiber exposure; the number of exposed tubules and the surface area occupied by tubule orifices were also measured. Friedman's 2-way analysis for block designs was employed. Results demonstrated that root-planed, non-acid treated specimens had an amorphous, irregular surface which corresponded to a smear layer.(ABSTRACT TRUNCATED AT 250 WORDS)

Influence of velocity and direction of surface-parallel cutaneous stimuli on responses of mechanoreceptors in feline hairy skin.

1. The responses of cutaneous mechanoreceptors in feline hairy skin were examined in vivo with systematic variations in the velocity and direction of stimulus motion across the receptive fields (RF). The mechanoreceptor classes studied were guard hair afferents, field afferents, down hair afferents, and slowly adapting type I (SAI) mechanoreceptors. A camel's hair brush, moved by a high-precision motor, provided surface-parallel stimulation at velocities ranging from 0.4 to 100 cm/s. The stimulating device and protocols were similar to those previously used to evaluate human perception, thus allowing direct comparison of the two sets of data. 2. Each mechanoreceptor produced highly reliable mean firing rates with repeated stimulation. All mechanoreceptors showed a growth in evoked activity with increased stimulus velocity. With few exceptions, the relationship between brush velocity and mean firing rate was well described by a power function throughout the range of velocities tested. The exponents of these power functions, reflecting the degree of velocity dependency for each mechanoreceptor, were largest for the field type 1 units (F1) and guard hair type 1 units (G1). 3. The capacity of the mechanoreceptors to discriminate velocity was examined in the context of signal detection theory. For each unit, a velocity discriminability estimate (velocity delta'e) was calculated for responses to 5 versus 10 cm/s brushing and 10 versus 20 cm/s. The G1 and F1 units exhibited the largest velocity delta'e values, which were comparable to human velocity discriminability (d'e) values. Thus these data show the quantitative parallel between the velocity discriminability of G1 and F1 mechanoreceptors and of human perception similarly tested. 4. Most mechanoreceptors generated different response rates with stimuli moving in opposing directions (in the proximal-distal axis of the hindlimb). However, no mechanoreceptor class showed a consistently preferred direction of movement. A directional delta'e value was calculated for each mechanoreceptor at each stimulus velocity. These values were quite variable, even within a single mechanoreceptor class. In general, a mechanoreceptor's directional delta'e value either 1) decreased with increasing velocity or 2) remained constant across velocities. The way in which human directional discriminability varies with stimulus velocity did not parallel the way in which mechanoreceptor's directional delta'e values varied with the same range of stimulus velocities. 5. Some mechanoreceptors were tested with both the standardized brush, which was smaller than most mechanoreceptors' RFs, and a much larger brush, which was at least twice the size of the mechanoreceptors' RFs.(ABSTRACT TRUNCATED AT 400 WORDS)

Functional Innervation of Cultured Skin Grafts

The aims of the present study were to determine 1) if grafts of cultured skin become innervated; and 2) whether tactile function of these grafts could be improved by implanting target tissue into them. Autologous skin equivalents were generated in vitro (30 d) for individual adult Sprague-Dawley rats. Some animals received pure skin equivalent grafts; others had target tissue consisting of 2-mm punch biopsies (normal skin or touch domes) inserted into their skin equivalents at the time of grafting. After 83 d, physiologic recordings were obtained from afferent nerves innervating the grafts. Tissue was processed for histology at various intervals. Silver staining of the tissues demonstrated many isolated nerve fibers in the dermis of cultured areas of skin as well as in implant zones. When grafts were rubbed with a glass rod or pinched with watchmaker forceps, impulses were evoked in nerves innervating both implant and cultured regions. In contrast, the afferent response to gently stroking grafts with a camel hair brush was severely reduced in cultured areas but was vigorous in implanted skin. Neuronal activity characteristic of type I neurons innervating touch domes was only found in cutaneous nerves innervating implants originally possessing domal tissue. Furthermore, grafts with good takes had better return of sensory function than grafts undergoing episodes of crusting. These results suggest that structural components or trophic factors present in implants enhanced the return of neural function related to the sensory modality of light touch; and this was also affected by the engraftment quality.

Control of Tobacco Budworms with Foliar Insecticides, 1991

Abstract Flue-cured tobacco was planted at the Central Crops Research Station, Clayton, NC, on 29 Apr in a field with a mix of Fuquay loamy sand and Norfolk loamy sand. Plots were 4 rows (45 inches apart) wide by 25 plants (ca. 55 ft) long, arranged in a randomized-complete block design with 10 treatments and 4 blocks. On 5 Jun, 10 uniformly sized and undamaged plants from each of the 2 left-most rows in each plot were tagged with surveyor's tape and artificially infested with a single 2-day-old laboratory-reared tobacco budworm larva. Larvae were transferred to the bud with a camel's hair brush. The 2 right-most rows provided an untreated buffer between plots. Sprays were applied with a Co2-pressurized sprayer through a single D2-33 full-cone nozzle per row at a rate of 25 gal/acre and 60 psi on 6 Jun. Four and lid after application, the number of surviving larvae on the tagged plants was counted. Budworm feeding damage (0-4) was determined after 14 d. On 2 Jul, all plants in the untreated buffer rows were cut off at 3-4 leaves above the ground. Suckers grew from the axils of the remaining leaves, and on 18 Jul all but one healthy, undamaged sucker were removed. A natural infestation of budworms and tobacco hornworms was present for this test. Sprays were applied on 9 Aug as described above. Four and 9 or 10 d after treatment, the number of surviving budworms and tobacco hornworms on 10 plants in each plot was counted. Before ANOVA, count data were transformed to count + 0.5. Treatments means were separated using the Waller-Duncan K-ratio t test (K = 100, a = 0.05). Means of untransformed data are presented.

Popular reality: A (hair)brush with cultural studies

(1991). Popular reality: A (hair)brush with cultural studies. Continuum: Vol. 4, Television and ..., pp. 5-18.

New Ichthyoliths from Ferromanganese Crusts and Nodules from the Central Indian Ocean Basin

Ferromanganese encrusted hardgrounds, their intraclasts and the nuclei of manganese nodules collected from the central Indian Ocean basin have yielded plentiful numbers of ichthyoliths. Forty well-known ichthyoliths, one new type and 35 new subtypes are encountered. To accommodate these newly recovered ichthyoliths, the coded descriptive system for the taxonomy of ichthyoliths (Doyle and Riedel 1979a and its later modifications) is updated herein. New ichthyoliths are described and illustrated. A majority of them are believed to be of Paleogene age. INTRODUCTION SYSTEMATICS The distribution of microscopic skeletal fragments of fishes or ichthyoliths has been studied in various DSDP sites from the world's oceans. Recent works of Edgerton et al. (1977), Kaneps et al. (1981), Doyle and Riedel (1979b, 1985a and 1985b), Gottfried et al. (1985) and Tway et al. (1985) have established biostratigraphic ranges of the ichthyolith subtypes, which can be used for correlation in otherwise unfossiliferous pelagic Tertiary sediments. The ferromanganese encrustations and the nodules collected during various cruises for the survey of polymetallic nodules in the central Indian Ocean basin (text-fig. 1, table 1) yielded many ichthyoliths in otherwise unfossiliferous substrates and nuclei of encrustations and nodules. The nuclei and substrates of ferromanganese nodules and encrustations are made up of burrowed and bored pelagic clays. The earlier described ichthyoliths are recognized and many new ichthyoliths are encountered. In this paper, the author has attempted to describe new ichthyoliths by modifying the coded descriptive system of ichthyoliths. MATERIAL AND METHODS The nuclei and substrates of the ferromanganese encrustations and nodules are chiefly of two types; altered basalts and pelagic claystones and clayclasts. Tie clayclasts are the intraclasts of burrowed and bored pelagic hardgrounds (Gupta, in prep.). The nuclei material was scraped with a sharp knife and broken into small pieces (0.5cm), dried, weighed and dispersed in sodium hexa-meta-phosphate then boiled in H202 for 4 hours. The material was sieved on a 62gm mesh screen. The fragmentary fish micro-remains were picked using a fine camel hair brush under a binocular microscope, placed on glass slides and then mounted in Canada balsam. These fish micro-remains were studied under a transmitted light microscope and identified by decoding the coded descriptors. The type material and subtypes of the newly described ichthyoliths are housed at the Geological Oceanography Division of the National Institute of Oceanography, Dona Paula, Goa 403 004, India. The taxonomy of ichthyoliths is determined by decoding the coded descriptive system given by Doyle et al. (1974), Dunsworth et al. (1975), Ramsey et al. (1976), Doyle and Riedel (1979a, 1980, 1985b), Gottfried et al. (1984), Tway et al. (1985) and Winfrey et al. (1987) and are described using the same 70' E 80' IO N \\I LEiAi890 I

Evaluation of Microencapsulated Curacron for Controlling Tobacco Budworm, 1990

Abstract A microencapsulated formulation of Curacron 4 CS (CS = capsule suspension) was compared with Curacron 8 EC against TBW larvae on cotton. Test insects were obtained from a colony of susceptible TBW maintained at the Southern Field Crop Insect Management Laboratory, Stoneville, Miss. Treatments were applied to 2-mo-old cotton plants under a spray table using 2 nozzles (650033 and 8002E) which respectively delivered 1.12 and 2.28 gal/acre. The AI was 0.25 lb/acre. The volume median diam of droplets in the selected plumes of the 650033 and 8002E nozzles averaged 200 and 300 microns in diam, respectively. Ten TBW larvae prefed on cotton plants for 48 h were placed with a camel hair brush on terminal leaves and on leaves in close proximity to the terminal of plants, 0, 1, 3, 5, and 7 days after spraying with Curacron. Untreated plants were used for each treatment. Mortality of the larvae was determined 5 d after exposure to Curacron. The experimental units were assembled in a split-split-plot design with 3 replications. Nozzles comprised the main plot, formulation was the sub-plot, and the days posttreatment were randomly assigned as sub-sub-plots. Each experiment was repeated 4 times and conducted on 21 Jun, 20 Jul, 2 and 3 Aug. Data were pooled over each date and analyzed as a repeated-measures analysis of variance (ANOVA).

Purkinje cell simple spike activity during grasping and lifting objects of different textures and weights

1. Three monkeys (2.5-3.5 kg) were trained to pinch an object between the thumb and forefinger and to lift it a vertical distance of 1.0-2.0 cm. Either the object weight (15, 65, or 115 g) or the surface texture (sand paper or polished metal) contacting the fingers could be varied. The object was equipped with a vertical position transducer, an accelerometer, and strain gauges that measured the grip force and the vertical load force. 2. In accordance with similar previously published studies on human subjects, it was found that monkeys appropriately scaled the grip forces according to the weight and coefficient of friction of the object. The grip force preceded the load force by 25 ms, and they both covaried with the changes in surface friction. 3. An analysis of electromyograms (EMGs) recorded intramuscularly from the muscles of the wrist and fingers including both flexors and extensors indicated that 26 muscles were active during pinching and lifting. Of these, 17 produced the maximum activity for the slippery surface and the greatest weight and the least activity with the roughest surface and lightest weight. 4. A total of 59 Purkinje cells and 123 unidentified units recorded from the paravermal and lateral cerebellar cortex were found to change their firing frequency during lifting the experimental object. 5. Increased discharge during the grasping and lifting was found for 56% (33/59) of the Purkinje cells and 80% (98/123) of the unidentified neurons, whereas 44% (26/59) of the Purkinje cells and 20% of the unidentified neurons decreased activity during the same period. 6. Significant modulations of the firing frequency with surface texture or object weight occurred for 59% (35/59) of the Purkinje cells and 67% (82/123) of the unidentified neurons. 7. One hundred and three Purkinje and unidentified neurons recorded in the paravermal and lateral region of the cerebellar cortex were examined for peripheral receptive fields, and of these, 43/103 (42%) responded exclusively to imposed displacements and tapping of muscles suggesting afferents originating from proprioceptors. A further 28/103 (27%) had exclusively cutaneous receptive fields on the hand that could be stimulated by brushing the skin lightly with a sable hair brush. Only six neurons demonstrated convergent cutaneous and proprioceptive receptive fields and no response to peripheral stimulation could be found for 26 neurons. No difference was found between the receptive fields of Purkinje cells and those of the unidentified neurons.(ABSTRACT TRUNCATED AT 400 WORDS)

A Brushing Method of Inoculation for Screening Tomato Seedlings for Resistance to Septoria lycopersici

Screening of tomato was more accurate by brush-inoculation of leaves than by dipping or spraying. An inoculum concentration of 10 6 spores per milliliter or higher was applied to both sides of leaves with a camel's-hair brush; pots containing inoculated seedlings were placed in shallow trays in a thin layer of water, and the inoculated seedlings were covered with a moisture-proof plastic canopy for 48 hr at 24°C in a greenhouse

Ovicide, Larvicide Trials, 1989

Abstract A greenhouse study was conducted at the Texas A&M University Research and Extension Center in Corpus Christi, TX, to measure the efficacy of binary mixtures combining Orthene and 3 pyrethroids against cypermethrin-susceptible (S) and -resistant (R) eggs/ neonates of TBW. Treatment efficacy was evaluated on eggs obtained from S and R strains of TBW (from ICI Americas). Cotton was planted in 1 gal pots on 4 Feb. Eggs (less than 24 h old) were placed on the upper surface of separate leaves (16-25 eggs/leaf) located near the shoot terminal of 4 flowering cotton plants/treatment (4 leaves with S eggs, 4 leaves with R eggs) with a camel's hair brush moistened with distilled water. The plants were placed in a row and spray application of each treatment was made 15 min after placement of eggs on leaves. Insecticide treatments were made with a CO2-pressurized (40 psi) backpack sprayer calibrated to deliver 4.4 gal/acre through 2, size 3X hollow-cone nozzles/row. All leaves that contained eggs were collected immediately after treatment and placed in covered plastic Petri dishes containing moistened filter paper. The eggs were held for 72-h in the laboratory, then inspected for unhatched eggs and dead or live larvae. Each treatment was replicated 4 times in a randomized block design. A replicate consisted of 1 leaf and 16-25 eggs, depending upon the number of eggs remaining on the leaf after removal from the plant and placement in the dish.

Dorsal raphe stimulation, 5-HT and morphine microiontophoresis effects on noxious and nonnoxious identified neurons in the medial thalamus of the rat

In single cell experiments, the characterization of the responses of medial thalamic neurons to noxious and nonnoxious stimulation was made to examine the effects of two substances involved in pain, morphine and 5-HT, and the action of one pain suppressor mechanism, dorsal raphe stimulation. Single cell activity was recorded in urethane anesthetized rats. Tail pinch and tail immersion in hot water were used as nociceptive stimuli. Skin strokes, air puffs and hair brushing were used as nonnociceptive stimuli. Morphine, 5-HT microiontophoresis and dorsal raphe stimulation were performed in all the recorded units. Fifty-eight percent from 61 medial thalamic recorded units responded both to noxious and nonnoxious stimulation; whereas only 18% and 24.6% of the units responded exclusively to noxious and nonnoxious stimulation, respectively. The noxious responding units were located in the most posterior portions of the medial thalamus. Dorsal raphe stimulation and 5-HT ejection prevented the excitation elicited by noxious input. Morphine ejection prevented both the noxious and nonnoxious input in medial thalamus, in a different population as compared to dorsal raphe stimulation or 5-HT ejection. These findings support the existence of a pain ascending mechanism mediated by an opioid-serotonergic interaction in the medial thalamus of the rat.

Control of Tobacco Budworm, 1988

Abstract Commercially grown tobacco was transplanted 13 May in Pender County, N.C., and 27 Apr in Sampson County. Because natural infestations were very light, 20 undamaged plants/plot were tagged and artificially infested with budworms from a culture maintained at North Carolina State University. A single 1-d-old larva was transferred from artificial diet to the bud of tagged plants using a camel's hair brush and allowed 24 h (Pender) and 96 h (Sampson) to become established before treatment. Treatments were arranged in a randomized complete block design with 4 replicates. Plots were 0.02 acres, 4 rows, separated laterally by a vacant row and on each end by 10-16-ft alleys. Insecticides were applied with a C02-pressurized backpack sprayer delivering 30 gal/acre through a single TG-3 nozzle (Pender, 24 Jun) or 16 gal/acre through a single TG-2 nozzle (Sampson, 13 Jun) at 60 psi. Tagged plants were examined for budworms at 3 and 13 DAT in Pender and at 4 and 10 DAT in Sampson. On the second date in each location, budworm damage was rated on all tagged plants. After final harvest and curing, tobacco was weighed and graded with the assistance of a government grader. Data were subjected to ANOVA. For analysis, budworm infestation was expressed as the proportion of plants infested and yield as lb/plot. In the table, infestation is presented as the percentage of plants infested.

Ovicide, Larvicide Trials, 1988

Abstract A small-plot field study was conducted in a commercial field near Taft, Tex., to measure the efficacy of 5 treatments against eggs and freshly hatched larvae of tobacco budworm. Treatment efficacy was evaluated on eggs obtained from a pyrethroid-susceptible strain of tobacco budworm (ICI laboratory colony maintained at the Texas A&M University Research and Extension Center at Corpus Christi). Treatments were compared in 5-row by 50-ft plots of cotton planted 7 Mar on 38-inch rows. Fresh eggs (24 h old) were placed on the upper surfaces of leaves (10-12 eggs/leaf) located near the shoot terminal of each of 6 flowering cotton plants/treatment with a camel’s hair brush moistened with distilled water. Treatments were applied 22 Jun, 30 min after placement of eggs on leaves, with a CO2-pressurized (40 psi) backpack sprayer calibrated to deliver 4.4 gal total spray/acre through 2 size 3X hollow-cone nozzles/row. Based on visual examination, the coverage of leaves and eggs with treatment sprays was optimal. At 6 h after application, all leaves that contained eggs were collected and placed individually into covered plastic Petri dishes containing filter paper moistened with distilled water. The eggs were held for 72 h, then inspected for unhatched eggs and dead or live larvae. Each treatment was replicated 3 times in a randomized complete block. A replicate consisted of 2 leaves and 18-22 eggs, depending on the number of eggs lost in the field.

Ovicide, Larvicide Trials, 1988

Abstract A small-plot field study was conducted in a commercial cotton field near Austwell, Tex., to measure the effects of 6 treatments on survival of tobacco budworm eggs and freshly hatched larvae of tobacco budworm. The eggs were obtained from pyrethroid-susceptible and pyrethroid-resistant strains of tobacco budworm (ICI laboratory colonies maintained at the Texas A&M University Research and Extension Center at Corpus Christi). Treatments were compared in 5-row by 50-ft plots of cotton planted 28 Apr on 30-inch rows. Each treatment was replicated 3 times in a randomized complete block. Treatments were applied with a CO2-pressurized (38 psi) backpack sprayer calibrated to deliver 4.4 gal total spray/acre through 2 size 3X hollow-cone nozzles/row. Plots were oversprayed with malathion 26 Jul to remove parasites and predators that could confound ovicide test results. Before the 27 Jul application, fresh eggs (24 h old) were manually placed on the upper surfaces of leaves (10-12 eggs/leaf) located near the shoot terminal of each of 6 flowering cotton plants/treatment with a camel’s hair brush moistened with distilled water. Resistant eggs were placed on leaves separate from susceptible eggs. A replicate consisted of 2 leaves and 18-22 eggs, depending on the number of eggs lost in the field. Treatments were applied to plants within 30 min of egg placement. At 1 h after application, all leaves that contained eggs were collected and placed individually into covered plastic Petri dishes containing filter paper moistened with distilled water. The eggs were held for 72 h, then inspected for unhatched eggs and dead or live larvae.

Ovicide, Larvicide Trials, 1988

Abstract A small-plot field study was conducted in a commercial cotton field near Austwell, Tex., to measure the effects of 5 treatments on survival of eggs and freshly hatched larvae of the tobacco budworm. The eggs were obtained from a pyrethroid-susceptible strain of tobacco budworm (ICI laboratory colony maintained at the Texas A&M University Research and Extension Center at Corpus Christi). Treatments were compared in 5-row by 50-ft plots of cotton planted 28 Apr on 30-inch rows. Each treatment was replicated 3 times in a randomized complete block. Treatments were applied with a CO2 pressurized (38 psi) backpack sprayer calibrated to deliver 4.4 gal total spray/acre through 2 size 3X hollow-cone nozzles/row. Fresh eggs (24 h old) were attached manually to the upper surfaces of leaves (10-12 eggs/leaf) located near the shoot terminal of each of 6 flowering cotton plants/treatment with a camel’s hair brush moistened with distilled water. Treatments were applied to plants within 30-min of placement of eggs on 13 Jul. At 4 h after application, all leaves that contained eggs were collected and placed individually into covered plastic Petri dishes containing filter paper moistened with distilled water. The eggs were held for 72 h, then inspected for unhatched eggs and dead or live larvae. A replicate consisted of 2 leaves and 18-22 eggs, depending on the number of eggs lost in the field.

Vegetable Oil Sprays of Larvin UCLF-5; Activity Against Tobacco Budworms Under Rainy Conditions, 1987

Abstract A small-plot field study was conducted to evaluate different spray formulations of Larvin UCLF-5 for efficacy against tobacco budworm larvae in cotton. Four treatments and an untreated check were compared in 1-row × 6.7-ft plots of cotton planted 16 Apr on 38-inch rows. Treatments and the untreated check were replicated 3 times in a randomized complete block design. All plots were artificially infested twice with neonatal tobacco budworm larvae (laboratory colony maintained at the USDA Field Crop Insect Management Laboratory at Stoneville, Miss.). The first release of larvae was made 2 days before application of treatments (6 Jul), and the second release was made 1 day before application of treatments (7 Jul). Using a camel's hair brush, larvae were placed in shootterminals of randomly chosen plants in each plot (60 larvae/plot/release). On 8 Jul, treatments were applied to plots by using a modified CO2-pressurized backpack sprayer equipped with a controUed-droplet atomizer (Micro Max/DR4; Micron, Houston, Tex.) operating at 2,000 rpm. The atomizer was powered by a 12 V battery. The flow rate was regulated with a size 4916-16 regulator orifice plate (Spraying Systems, Wheaton, 111.) at 25 psi, which produced a finished spray volume of 1.3 gal/acre. The atomizer was held 10 inches above the row. At the time of treatment, the wind was 5-11 mph from SE (row direction was E to W), RH was 61%, and ambient temperature was 81°F. To prevent cross contamination of treatments from spray drift, 4 untreated buffer rows of cotton were planted between each plot, and a 4- × 3-ft plastic shield was carried next to the atomizer during treatment application (the shield was held 4 ft NW from the atomizer). Thirty-five min after application, a brief, hard rainfall of about 0.3 inches occurred at the test site. Treatment efficacy was evaluted 7 days after the application by inspecting 40 squares and 40 bolls/plot for budworm feeding. Numbers of larvae found in squares and bolls also were recorded.

Tobacco Budworm Control with Various Formulations of Bacillus Thuringiensis, 1987

Abstract Flue-cured tobacco was transplanted at the Central Crops Research Station, Clayton, N.C., on 6 May in a Norfolk loamy sand. Plots of 4 rows (45-inch row centers) × 60 ft (35 plants) were arranged in a randomized complete-block design for a test containing 10 treatments and 4 replicates. On 16 Jun, 15 uniformly sized and undamaged plants from each of the 2 left-most rows in each plot were tagged and infested with a single 2-day-old laboratory-reared tobacco budworm larva. Larvae were transferred to the plant bud with a camel’s hair brush. Two rows provided an untreated buffer. Treatments were applied with a C02-pressurized sprayer on 18 Jun through a single D2-33 full-cone nozzle per row at the rate of 25 gal/acre and 60 psi. Five and 11 days after treatment, the number of surviving larvae on the tagged plants as counted. After 13 days, budworm feeding damage was rated (0-4), and leaf consumption (0.1 leaves consumed) was estimated on all tagged plants/plot. On 10 Jul, all plants in the buffer rows were cut off at 3-4 leaves above the ground. Suckers grew from the axils of the remaining leaves, and on 29 Jul all but one healthy sucker were removed. Due to the presence of a naturally occurring budworm population, 20 plants containing a single small larva (<3rd instar) were selected and tagged on 12 Aug. Treatments were applied on 13 Aug as described above. Four- and 11-day counts of surviving budworms were made on tagged plants. A 14-day damage rating (0-4) was made on 27 Aug. Prior to ANOVA, count data were transformed to . Treatment means were separated using the Waller-Duncan K-ratio i-test (K = 100, α = 0.05). Means of untransformed data are presented.

Residual Comparison of Chlorpyrifos Against Adult Cat Fleas and Adult Flea Emergence, 1987

Abstract Nylon shag pile carpet discs (5 inches diam) were treated with either 11.7% Dursban ME, 41.5% Dursban LO or Pennwalt 23.5% TD 2247. Each formulation was mixed with water and applied at the rate of 1 gal/1000 ft2. Each carpet disc was treated by the use of a 1 gal Hudson pressurized hand sprayer calibrated to deliver 0.23 oz/s at 20 psi. Control carpet discs were sprayed with water only. On the day of treatment, 7, 14, and 28 days posttreatment, a treated carpet disc was placed in the bottom of a 1 gal jar and ca. 25 adult cat fleas were added. All treatments were replicated 3 times at each time interval and the experiment was replicated twice. At 24 h posttreatment, dead and live fleas were recovered by brushing each carpet disc vigorously for ca. 1 min with a hair brush within a 5 gal plastic bucket. The discs were then submerged in water to recover any additional live fleas. Nylon shag pile carpet discs (3.5 inches diam) were treated as described above and all formulations were tested for their effects on adult cat flea emergence. On the day of treatment, 7, 14, and 28 days! posttreatment, ca. 0.25 g of dried blood, ground cat chow mixture (3:20), and 25 cat flea eggs were placed within the fibers of each treated carpet disc. \ Infested discs were then placed into 1 pt fonda containers, covered with a fine cloth screen to contain emerging adult fleas and stored at 25°C at 80% RH. - All treatments at each time interval were replicated 3 times and controls replicated 6 times. When >50% of the adult fleas had emerged in the control containers, treatments were evaluated for % adult emergence by recovering adult fleas as described above. In both tests carpet discs were used only once for each test interval. All carpet discs were stored at ca. 25°C between infestation periods.

Ovicidal Activity of Larvin and Ammo Against Pyrethroid-Susceptible and Resistant Strains of Tobacco Budworm, 1987

Abstract Two small-plot studies were conducted in the field at the Texas A&M University Research and Extension Center at Corpus Christi to measure the effects of 4 treatments on survival of eggs and freshly hatched larvae of tobacco budworm. In Test 1, treatments were evaluated on eggs obtained from a pyrethroid-susceptible strain (S-strain) of tobacco budworm (laboratory colony maintained at the USDA Field Crop Insect Management Laboratory at Stoneville, Miss.) Treatments in Test 2 were evaluated on a pyrethroid-resistant strain (R-strain) of tobacco budworm (laboratory colony [PEG-87] maintained at ICI Americas at Pikeville, N.C.). Experimental methods were identical for both tests. Treatments were compared in 1-row × 30-ft plots of cotton planted 19 Mar on 38-inch rows. Using a camel's hair brush moistened with distilled water, fresh eggs (3- to 10-h-old) were attached manually to the upper surfaces of leaves (10 eggs/leaf) located near the shoot terminal of each of 24 flowering cotton plants/treatment. Within 30 min following placement of eggs on plants, treatments were applied to plants by using a CO2-pressurized (35 psi) backpack sprayer. The sprayer was calibrated to deliver 4.5 gal total spray/acre through 2 size 3X hollow-cone nozzles/row. Based on visual estimation, coverage of leaves and eggs with treatment sprays was optimal. Four hours after application, all leaves containing eggs were collected and placed individually into covered plastic Petri dishes and held in a laboratory temperature cabinet for 72 h (constant 78°F and 80% RH) then inspected for unhatched eggs and dead or live larvae. Each treatment was replicated 6 times in a completely randomized design. A replicate consisted of 6 leaves and 47-57 eggs, depending on the number of eggs lost in the field.