Mite Counts Research Articles

Apple, Effectiveness of Combinations of Phosalone with Methomyl or Penncap Min the Control of P. Flavedana, 1979

Abstract Three adjacent 24-tree plots (12 in each of 2 adjacent rows - Winesap cultivar) were included in this experiment conducted at Massies Mill, Virginia. Materials were applied to one side (alternated on successive dates) only on each spray date with a Swanson airblast sprayer calibrated for 6X spraying to deliver 25 gpa (233.84 liters/ha) from one side, at 2 mph (3.22 km/hr) with a pump pressure of 100 psi (7.03 kg/cm2) . Treatments and the azinphosmethyl standard were applied on May 30, Jun 6, 13, 20, 27, Jul 9, 16, 25, Aug 1, 10, 17, 28 (Table 1). Leafroller spinups were collected from each plot, the grower's orchard, and two adjacent integrated plots and examined microscopically in the laboratory on Aug 10 (Table 2). Fruit examinations were made in the orchard on Aug 28 (Table 3). European red mite populations caused some bronzing by late summer so an Aug 29 mite count was taken. Results are presented in Table 4. The Henderson-McBumie mite brushing technique was used to obtain these data from a 25-leaf sample (5 leaves from each of 5 trees.

Apple, Airblast Treatments, 1979

Abstract Treatments consisting of 7 applications were applied to mature frees on semidwarf roofstocks with a Bean 1229, three point hitch, power-take-off sprayer, at 50 gal/A. Each treatment consisted of 4-cell plots, each of which had 2 Winesap and 2 York trees surrounded by treated guard trees. Other sprays applied to plot areas were benomyl, Thylate, Karathane, streptomycin, Polyram, captan, Dikar, Omite, and Plictran. Midseason mite counts were made. Apples were evaluated at harvest for damage by leafrollers, scale, and effects on finish. Leafroller damage was determined to be either “early season” or “late season” depending on the amount of rot or decay around the feeding site.

Evaluation of Acaricides on Cotton, 1979

Abstract Six acaricides were applied to cotton September 21 to evaluate effectiveness for control of the carmine spider mite. The spray treatments were made with a back pack CO2 sprayer using 40 gpa and 40 psi. Plots were 20 ft long and replicated 4 times. Mite counts represent larvae, nymphs and adults.

THREE METHODS OF SAMPLING MITES PHORETIC ON BARK BEETLES: A COMPARISON

AbstractWhen a few large trees are to be sampled, emergence traps provide more reliable counts of mites that are phoretic on southern pine beetles than either removal of bolts or removal of 100 cm2 bark discs. When a large sample from smaller trees is required, removal of bolts is preferable to removal of disc samples. Emergence traps or bolt samples are preferable to disc samples because: (1) fewer mites are lost during transportation and rearing; (2) mites are not left on the xylem; (3) fewer die from desiccation during rearing; and (4) fewer non-phoretic stages accumulate in the collecting medium.

Apple, Test of Acaricides, 1978

Abstract Experimental sprays were applied to runoff to single-tree plots in a randomized block design with 2 replicates of Golden Delicious and 2 Red Delicious, both spur-type trees. Experimental sprays were applied with a spraygun from a truck-mounted John Bean sprayer equipped with a 35-gpm pump on Jun 30, Jul 10, and Aug 8 to all plots. General purpose sprays of captan 50W 1.5 1b, Guthion 50W 0.25 lb, and Sevin 50W 1.0 lb/100 gallons dilute were applied at ca. 2-wk intervals throughout the summer. Average temperatures were: May 58.6°F, Jun 68.5°F, Jul 70.4°F, and Aug 74.1°F. Rainfall in inches averaged: May 5.67, Jun 3.24, Jul 7.98, and Aug 2.46. Effectiveness of the test materials on the European red mite, two-spotten spider mite, and A.fallacis was evaluated by making several counts of mites on random samples of 20 leaves/tree, 80 leaves/treatment. Mite population pressure was moderate throughout the season.

Control of Texas Citrus Mite with Acaricides, 1978

Abstract Nine treatments were evaluated for control on lemon trees (20 years old) using 5 gal spray/tree on Apr 14. Sprays were applied with a spray gun (pistol-type) from a John Bean sprayer using 400 psi. Three-tree plots were replicated 4 times in a randomized block design. The daily average maximum temperature during the test was 88°F and there was no rainfall. The mite count on Apr 11 was 16.48 mites/leaf. There was an occasional citrus red mite found during the counts. This grove had a history of the Texas citrus mite during Nov and Dec of 1970 reaching a high of 23.78 mites/leaf on Nov 25. A slight infestation was found from Oct to Dec 1972 reaching a high of 1 mite/leaf on Oct 27, but no Texas citrus mite since.

Apple, Insecticide Tests, 1978

Abstract The experimental and standard insecticides were applied in comparative tests to 20+-yr-old Winsap trees 4 times from early June to early August. The trees were sprayed to runoff with a Bean 35-gal/min pump operating at 540 psi. The last application was applied with a Hardie sprayer operating at 600 psi. The treatments were applied to single trees, replicated 5 times in a randomized, complete-block design. Other materials used and dates of application were as follows: Apr 26--captan, sulfur, Systox; May 3--captan, Karathane; May 15--Cyprex, Karathane; May 22--captan, Sevin; May 30 and Jun 14--captan, Karathane; Jun 27 and Jul 17--captan, Topsin M; and Aug 7--Phaltan, Topsin M. These materials were applied to all treatments at the rate of 100 GPA (3X concentrate) with a Hardie 525 air-blast sprayer. A preharvest and harvest examination were made for insect injury and finish rating on the harvest examination. Mite counts were made on Jul 20 and Aug 24.

Greenhouse Ornamentals, Two-Spotted Spider Mite Control, California, 1978

Abstract An experiment was conducted to evaluate the efficacy of 9 experimental and 2 standard acaracides for control of two-spotted spider mites. Plants were maintained in 6-inch pots on raised greenhouse benches. A treatment consisted of 1 plant and was replicated 4 times on red ti and 5 times on neanthe bella palm. Plants were sprayed to the point of runoff utilizing a hand sprayer at 60 psi and a 5002 nozzle on May 15’78. Mite counts were made before application on May 11’78 and at 7-day intervals following application by counting the number of mites (adult and immature) on 1 leaf per plant on red ti and 3 leaflets per plant on neanthe bella palm.

Apple, Miticide Evaluation Experiment, 1978

Abstract All acaricide treatments and the water control were applied in a manner to duplicate the alternate-row application technique employed by many commercial growers. A Swanson airblast sprayer, calibrated to deliver 25 gal/acre (94.64 liter/ha) at 100 psi (7.03 kg/cm2) at a ground speed of 2 mph (3.22 km/hr) when spraying one side of the row, was used to apply all materials on each spray date. Each plot consisted of a single row of 35 trees of 8-yr-old Red Del icious. Samples for the Plictran standard included in the tables were taken from similar adjacent trees in the remainder of the 4-acre block. Four subsamples of 25 leaves collected from each of 4 trees, spaced evenly along the treatment row were collected in plastic bags, placed in an ice chest, and taken to the laboratory where they were brushed following the Henderson-McBurnie method. Counts of European red mites, European red mite eggs, and Apple rust mites were recorded. Two applicationsweremade, the first on Jul 16 to the south side ofthe row and the second on Jul 28 to the north side. Countswere madeon Jul 15, 18, 25, 28, and 29. Data are presented as percent change between the two counting dates indicated in each table. The average number of mites or mite eggs is also included to give relevance to the percentages. No phytotoxic effects were noted.

Citrus Red Mite Control with Acaricides, 1978

Abstract Experimental sprays were applied with a Myers speed sprayer to 5-tree plots and 4 replicates. Sprays were applied at 150 gpa and 400 psi on Apr 12. The spray pattern was adjusted to cover the height of trees. The tractor speed was 2 mph. Mite counts represent both immature and adult stages beginning with a precount Apr 8 of 9.04 mites/leaf. Treatments were evaluated by sampling 50 leaves selected at random per plot. Daily maximum temperature during the test in April was 88°F and 93°F for May. There was no rainfall.

Citrus Rust Mite Control, 1978

Abstract Experimental acaricides were compared to Vendex in a completely randomized experiment on 20-yr-old grapefruit trees (30 ft x 25 ft spacing). Each treatment was replicated on three single-tree plots by hand gun of a John Bean Model 1010-MTBT sprayer at 225 psi, ca. 15 gal/tree. Treatments were applied on Jul 10, with citrus rust mite counts made at 30-day intervals posttreatment. Eighteen fruit were selected at random in each tree, and citrus rust mites were counted on the top, median, and bottom of each fruit using a 10X handlens with a 1-cm2 grid.

Mite Control on Texas Citrus, 1978

Abstract Six acaricide treatments and a control were arranged in a completely randomized design with each treatment replicated on 6 single trees. The 4-yr-old grapefruit trees, on a 24 ft x 24 ft spacing on sandy loam soil, were sprayed by hand gun with a John Bean Model 1010-MTBT sprayer at 225 psi, using ca. 10 gal/tree. Treatments were applied on May 28 and mite counts made at 30-day intervals posttreafment. Twelve fruit/tree were selected at random and rust mite were counted on the top, median, and bottom of each fruit using a 10X handlens with a l-cm2 grid. Texas citrus mite were counted by collecting 15 to 20 leaves/tree at random, brushing the mites from leaves onto counting plates with a Henderson-McBurnie mite brushing machine, and counting at 40X under a binocular microscope. Acaraben and efhion + 1% citrus spray oil were the standard acari cides.

House dust mite sensitivity in childhood asthma.

The clinical features of perennial asthmatic children with a skin or bronchial reaction to the house dust mite (Dermatophagoides pteronyssinus) were compared with those of asthmatic children without mite sensitivity. Mite sensitive asthma was characterised by an early age of onset of symptoms, these being predominantly nocturnal. A history of wheezing precipitated by dust exposure, during vacuuming, bedmaking, or dusting was present in 52% of cases. Asthmatic children with mite sensitivity were more likely to have been born at the time of the year when mite counts were highest. This was consistent with the idea that allergy may be associated with a period of susceptibility to sensitisation in early infancy.

Tyrophagus putrescentiae: an allergenically important mite.

The incidence of positive skin tests to the mite Tyrophagus putrescentiae was measured and compared with skin reactions to Dermatophagoides pteronyssinus and other allergens in Australian and New Guinean populations, and mite counts were determined in Sydney and New Guinea houses. Positive reactions to T. putrescentiae were as frequent as those for D. pteronyssinus in asthmatics in Sydney and were the commonest positive reactions in the normal New Guinea population. T. putrescentiae-specific serum IgE levels were determined and some IgG cross-reactions of D. pteronyssinus and T. putrescentiae antigens were demonstrated. It is suggested that T. putrescentiae is an important source of allergen and should be considered whenever D. pteronyssinus is thought to be a problem. A convenient method for culturing and isolating T. putrescentiae is described.

Apple, Test of Acaricides, 1977

Abstract Experimental sprays were applied to run-off to single-tree plots in a randomized block design with 2 replicates of Golden Delicious and 2 Red Delicious, both spur-type trees. Experimental sprays were applied with a spraygun from a truck-mounted John Bean sprayer equipped with a 35 gpm pump on June 13, July 8 and July 22 to all plots. General purpose sprays of 1.5 lb captan 50W, 0.25 lb Guthion 50W, and 1 lb Sevin 50W/100 gallons dilute were applied at intervals of ca. 2 weeks throughout the summer. Average temperatures were: May 63.88°F, June 66.23°F, July 74.34°F, and August 72.67°F. Rainfall in inches averaged: May 0.88, June 2.91, July 5.75, and August 2.57. Effectiveness of the test chemicals on the European red mite, twospotted spider mite, and A. fallacis was evaluated by making several counts of mites on random samples of 20 leaves/tree, 80 leaves/treatment. Mite population pressure was moderate throughout the season.

Neanthe Bella, Twospotted Mite Control, 1977

Abstract Three acaricides were tested for their effect on the twospotted spider mite population infesting neanthe bella palms in 3 in.pots in a greenhouse. Sprays were applied by handspraying until foliage was thoroughly wet. Five replicates were treated with each material and compared to an untreated check. Counts of eggs and mites were made on a 1 cm square of an infested leaflet. These counts were made before treatment and 1, 7, and 14 days after treatment.

Control of Two-Spotted Spider Mites on Strawberries, 1971

Abstract Plictran was compared with a mixture of Kelthane + Tedion. The variety ‘Midway’ was selected because of its susceptibility to attack by mites. Both treatments were applied with a Kinkelder (Model - Marvel) low volume row crop sprayer with a 3-sided row %fop head. Sprays were applied at the rate of 10 gal/acre at 15 psi. The air velocity produced by the sprayer was 160-180 mph. The experimental design was a randomized complete block design with 5 replications. The plots were 30 ft long and 3 rows wide, the center row being used as the record row. All rows were planted on a 42-inch row spacing. Check plots were obtained by covering certain rows with clear 4 mil polyethylene plastic film. Check plots remained covered for 12 hr. All samples for mite counts consisted of 5 trifoliate leaves per plot. The record row was located 12.25 ft from the center of the sprayer.

Apple, Integrated Test, 1976

Abstract Several insecticide-acaricide programs were evaluated for insect control, mite suppression, and influence on the predator Stethorus punctum. Sprays were applied to 2-tree plots in a randomized block design with each plot consisting of a Red Delicious and a Golden Delicious tree. Each treatment was replicated 3 times. Treated plots were separated by others not sprayed with insecticides. Treatments were applied as 6X concentrates with a Friend Airmaster 393 sprayer at 25 gpa/alternate side spray driven at 2 mph. Spray dates for the insecticide treatments were: April 30, May 5, 13 and 24, June 3, 11 and 22, July 2, 16, 23 and 30, August 6 and 20. One plot was sprayed on all the dates listed with 114 g Guthion 50W and 1 lb Zolone 25W/acre/alternate side. Four other plots were sprayed with the same mixture except on July 16, 23 and 30, and August 6. On all four of these dates one plot was treated with 228 g GCP-5126 50W/ acre/alternate side spray. Another plot was treated with 1 lb GCP-5126 50W/acre on both sides on July 16 and 30. A third plot was treated with 114 g GCP-5126 50W/acre/alternate side spray on July 16, 23 and 30, and August 6. A fourth plot was treated with 342 g GCP-5126 50W in complete sprays on July 16 and 30. Fungicides applied as 6X concentrates as needed during the season were: Cyprex, Polyram, sulfur, Benlate, captan, and zineb. Average temperatures were: May 57.74° F, June 71.30° F, July 70.09° F, August 67.92° F, and September 62.78° F. Rainfall in inches averaged: May 5.68, June 2.63, July 4.86, August 2.62, and September 4.49. Effectiveness of the test chemicals on the European red mite was evaluated by making several counts of mites on samples of 20 leaves/tree, 60 leaves/treatment. The effectiveness of sprays on the predator. S. punctum was evaluated by 3-min counts of adults and larvae around the periphery of the test trees. European red mite and S. punctum data were taken from Red Delicious trees. Effectiveness on the apple aphid was evaluated by counting the number of infested terminals/10 terminals/tree and calculating the percent infested. The number of aphid infested leaves/terminal was also determined. For each treatment the number of apple aphids/most infested leaf/infested terminal was also counted. Effectiveness of the treatments on the tufted apple budmoth (TABM) was determined by counting the number of live larvae/tree and the number of larval sites or shelters/ tree. Effectiveness in preventing fruit injury by TABM larvae was evaluated by scoring: (1) all drops after July 1; (2) 100 Red Delicious and 50 Golden Delicious apples on the plot trees on Aug 23; and (3) a harvest sample of 100 Golden Delicious apples/plot tree on Sep 20. Russeting of Golden Delicious apples was scored by rating 50 apples/plot tree as having: no russet, slight russet, moderate russet and severe russet. The categories were ranked 1, 2, 3 and 4, respectively.

Apple, Test of Acaricides, 1976

Abstract Experimental sprays were applied to run-off to single-tree plots in a randomized block design with 2 replicates of Golden Delicious and 2 Red Deiicious, both spur-type trees. Experimental sprays were applied with a spray gun from a truckmounted John Bean sprayer equipped with a 35 gpm pump on June 24, June 30, and July 15 to all plots except those treated with Sumithion and Vydate “L”. The Sumithion plot listed first in Tables 1 and 2 received only one spray on June 24 and the second Sumithion plot received the first and second sprays on June 24 and June 30. The Vydate “L” treatment was applied on June 24, June 30, July 8, July 15, and July 26. General purpose sprays of 1.5 lb captan 50W, 0.25 lb Guthion 50W, and 1 lb Sevin 50W/100 gallons dilute were applied at ca. intervals of 2 weeks throughout the summer. Average temperatures were: May 57.74° F, June 71.30° F, July 70.09° F, August 67.92° F, and September 62.78° F. Rainfall in inches averaged: May 5 . 6 8 , June 2 . 6 3 , July 4 . 8 6 , August 2 . 6 2 , and September 4 . 4 9 . Effectiveness of the test chemicals on the European red mite, twospotted spider mite, and A . fallacis was evaluated by making several counts of mites on samples of 20 leaves/tree, 80 leaves/treatment.

Commercial Evaluation of Acaricides For Rust Mite Control, 1976

Abstract Each acaricide treatment was applied to a separate row of 5 - year - old grapefruit tre,es (50 trees/row). Tree spacing was 24 ft x 18 f t , with an unsprayed guard row between treatments. All applications were made by a John Bean Model-F-357-CP speed sprayer, with nozzle adjustment, pressure and speed regulated to apply 250 gal of spray per acre. Treatments were made i n i t i a l l y on May 11'76 and reapplied on Jul 22'76. Mite counts were made at 30-day-intervals after treatment. At each counting date 50-100 leaves were collected at random from each treatment and examined microscopically for rust mite. Density of l i ve rust mites per leaf was rated on the following scale: 0 = no mites; 1 = 1-5; 2 = 6-10; and 3 = ^ 1 0 mites per leaf. Acaraben was the standard acaricide.