CONTAGIOUS DISTRIBUTION IN THE EUROPEAN RED MITE, PANONYCHUS ULMI (KOCH), AND A METHOD OF GRADING POPULATION DENSITIES FROM A COUNT OF MITE-FREE LEAVES

1960 ◽  
Vol 38 (3) ◽  
pp. 645-653 ◽  
Author(s):  
D. P. Pielou
Keyword(s):  
Panonychus Ulmi ◽  
Total Count ◽  
Population Densities ◽  
Leaf Sample ◽  
Apple Trees ◽  
Assessment Of Performance ◽  
Narrow Zone ◽  
European Red Mite ◽  
Mite Density ◽  
The Mean

Examination of a large number of 100-leaf samples shows that the European red mite is distributed contagiously, not randomly, on leaves of apple trees. When the mean number of mites per leaf is plotted against the proportion of mite-free leaves for the corresponding sample, the points fall in a narrow zone, steepest and narrowest at the lower densities. Following application of miticides to heavily infested trees, it is usual to summarize the findings of the tests by grading the performance of the chemicals as excellent, good, etc. according to mite density as determined by s total count from the 100-leaf sample. A method is outlined, in which, by making use of plotted values, a count of mite-free leaves only is sufficient to allow the assessment of performance in such categories.

SAMPLING SYSTEMS FOR EUROPEAN RED MITE, PANONYCHUS ULMI (ACARINA: TETRANYCHIDAE), EGGS ON APPLE IN NOVA SCOTIA

1973 ◽  
Vol 105 (12) ◽  
pp. 1519-1523 ◽  
Author(s):  
H. J. Herbert ◽  
K. P. Butler
Keyword(s):  
Nova Scotia ◽  
Apple Orchard ◽  
Panonychus Ulmi ◽  
Population Estimates ◽  
Population Densities ◽  
European Red Mite ◽  
Tree Population ◽  
Sampling Systems ◽  
Mature Apple ◽  
Whole Tree

AbstractA study was conducted in a mature apple orchard in Nova Scotia to compare the density of eggs of the European red mite, Panonychus ulmi (Koch), over the whole tree to their density on a selected area using a random selection and standard selection technique. Both methods provided nearly equivalent estimates of population densities for generations 2 and 4 but not for generation 3. The population estimates based on sampling from the selected area overestimated the whole tree population.Optimum allocation of sampling resources may be obtained by sampling a small number of clusters from each of a large number of trees.

THE EGG AND OVIPOSITION SITE OF DERAEOCORIS NEBULOSUS (HEMIPTERA: MIRIDAE) ON APPLE TREES

1980 ◽  
Vol 112 (5) ◽  
pp. 527-528 ◽  
Author(s):  
J. P. McCaffrey ◽  
R. L. Horsburgh
Keyword(s):  
Panonychus Ulmi ◽  
Oviposition Site ◽  
Pest Species ◽  
Apple Orchards ◽  
Apple Trees ◽  
European Red Mite ◽  
Important Pest ◽  
Ornamental Trees ◽  
Trees And Shrubs ◽  
Oviposition Sites

The predaceous mirid Deraeocoris nebulosus (Uhler) is found on more than 50 species of ornamental trees and shrubs where it feeds on several important pest species (Wheeler et al. 1975). It is a common mite and aphid predator in commercial apple orchards in Virginia (Parrella et al. 1978). Wheeler et al. (1975) described the nymphal stages and biology, but made no mention of the egg or oviposition site. We describe the egg and oviposition site which we discovered while studying various predators of the European red mite, Panonychus ulmi (Koch), in Virginia apple orchards. Eggs and oviposition sites of other predaceous mirids associated with apple have been described (Kullenberg 1942; Collyer 1952, 1953; Sanford 1964; Horsburgh and Asquith 1968, 1970).

ESTIMATING MITE POPULATIONS IN SOUTHERN OREGON PEAR ORCHARDS

1971 ◽  
Vol 103 (1) ◽  
pp. 67-71 ◽  
Author(s):  
P. H. Westigard ◽  
L. D. Calvin
Keyword(s):  
Sample Size ◽  
Coefficient Of Variation ◽  
Spider Mite ◽  
Sampling Methods ◽  
Mite Species ◽  
Panonychus Ulmi ◽  
Species Variation ◽  
European Red Mite ◽  
Mite Density ◽  
Two Spotted Spider Mite

AbstractStudies were conducted in southern Oregon pear orchards to develop sampling methods for assessment of mite abundance. Those species included in the investigation were the two-spotted spider mite, Tetranychus urticae Koch; European red mite, Panonychus ulmi (Koch); yellow spider mite, Eotetranychus carpini borealis (Ewing); and the predaceous phytoseiid Typhlodromus occidentalis Nesbitt.The results show that five leaves on one limb per tree are adequate to include representative numbers of the four mite species. Variation in mite densities between trees, even of the same variety, was quite high. The sample size (numbers of trees) required for assessing mite density can be calculated provided that an estimate of the coefficient of variation (S/X) is available.

scholarly journals Soybean Oil as a Summer Spray for Apple: European Red Mite Control, Net CO2 Assimilation, and Phytotoxicity

HortScience ◽  
2003 ◽  
Vol 38 (2) ◽  
pp. 234-238 ◽  
Author(s):  
Renae E. Moran ◽  
Dennis E. Deyton ◽  
Carl E. Sams ◽  
Charles D. Pless ◽  
John C. Cummins
Keyword(s):  
Soybean Oil ◽  
Co2 Assimilation ◽  
Panonychus Ulmi ◽  
Apple Trees ◽  
Malus Sylvestris ◽  
European Red Mite ◽  
Net Co2 Assimilation ◽  
Mite Control ◽  
Leaf Residue ◽  
Control Net

Soybean [Glycine max (L.) Merrill] oil was applied to apple trees [Malus sylvestris (L.) Mill var. domestica (Borkh.) Mansf.] as a summer spray in six studies to determine if it controls European red mites [Panonychus ulmi (Koch.)], how it affects net CO2 assimilation (A), and if it causes phytotoxicity. Sprays of 0.5%, 1.0%, and 1.5% soybean oil {TNsoy1 formulation [soybean oil premixed with Latron B-1956 (LAT) spreader-sticker at 10 oil: 1 LAT (v/v)]} reduced mite populations by 94%. Sprays of 1% and 2% soybean oil reduced mite populations to three and four mites per leaf, respectively, compared to 25 per leaf on water-sprayed plants. Soybean oil concentrations of 1.0% and 1.5% applied to whole trees reduced A for less than 7 days. Phytotoxicity did not occur when soybean oil was applied with an airblast sprayer at concentrations of 1.0% and 1.5% or with a mist bottle at 2%. Phytotoxicity occurred when soybean oil was applied with a mist bottle at 4% and 6%, which left soybean oil leaf residues of 0.22 to 0.50 mg·cm-2. No phytotoxicity occurred with 4% SunSpray, which resulted in a mean leaf residue of only 0.13 mg·cm-2. Spraying 1% soybean oil tended to give better mite control than 1% SunSpray Ultra-Fine oil, but caused greater oil residues and a greater reduction in A.

COMPARISONS BETWEEN AN EXOTIC AND AN ENDEMIC PHYTOSEIID MITE PREDATOR (ACARINA: PHYTOSEIIDAE) IN BRITISH COLUMBIA

1974 ◽  
Vol 106 (7) ◽  
pp. 773-776 ◽  
Author(s):  
R. S. Downing ◽  
T. K. Moilliet
Keyword(s):  
British Columbia ◽  
Resistant Strain ◽  
Panonychus Ulmi ◽  
Phytoseiid Mite ◽  
Population Densities ◽  
Amblyseius Fallacis ◽  
European Red Mite ◽  
Mite Predator ◽  
Phytoseiid Predator

AbstractIn 1972, an organophosphate resistant strain of the phytoseiid predator Amblyseius fallacis (Garman) from Michigan compared favourably with the endemic Typhlodromus occidentalis Nesbitt, from Summerland, B.C., in laboratory and greenhouse trials against European red mite, Panonychus ulmi (Koch), and was later released into an orchard. By August 1972, A. fallacis had decreased whereas population densities of T. occidentalis increased. Examination of leaves and bark from the trees, and weeds, grass, and litter beneath the trees in 1973 confirmed that A. fallacis failed to survive in the Okanagan environment.

THE EFFECT OF EUROPEAN RED MITE, PANONYCHUS ULMI (ACARINA: TETRANYCHIDAE), INFESTATIONS ON N, P, AND K CONCENTRATIONS IN APPLE FOLIAGE THROUGHOUT THE SEASON

1973 ◽  
Vol 105 (2) ◽  
pp. 263-269 ◽  
Author(s):  
H. J. Herbert ◽  
K. P. Butler
Keyword(s):  
Chemical Treatment ◽  
Panonychus Ulmi ◽  
Apple Trees ◽  
Seasonal Trends ◽  
European Red Mite ◽  
Phosphorus And Potassium ◽  
Nitrogen Phosphorus

AbstractSeasonal trends of the percentage of nitrogen, phosphorus, and potassium were measured in the foliage of apple trees infested with the European red mite, Panonychus ulmi (Koch), at four population levels created by the action of predators and/or chemical treatment.It was shown that by early September the concentrations of these nutrients; particularly nitrogen, were significantly depressed by high P. ulmi populations.

Occurrence and Food of Some Coccinellids (Coleoptera) in Ontario Peach Orchards

1964 ◽  
Vol 96 (9) ◽  
pp. 1149-1155 ◽  
Author(s):  
Wm. L. Putman
Keyword(s):  
Myzus Persicae ◽  
Second Generation ◽  
Green Peach Aphid ◽  
Adalia Bipunctata ◽  
Panonychus Ulmi ◽  
Population Densities ◽  
European Red Mite

AbstractTen species of the larger, primarily aphidophagous, coccinellids were present in peach orchards of the Niagara Peninsula. Adalia bipunctata (L.) and Coccinella trifasciata perplexa Mulsant were the commonest. All were most numerous in the spring while the green peach aphid, Myzus persicae (Sulzer), was present but their population densities were low at all times, apparently because suitable prey was scarce. They were not attracted to dense populations of the European red mite, Panonychus ulmi (Koch), and were of no importance as predators of peach pests.At least 7 species were bivoltine but the second generation was only partial.

RELATIVE DENSITIES OF PREDACIOUS AND PHYTOPHAGOUS MITES ON THREE VARIETIES OF APPLE TREES

1967 ◽  
Vol 99 (7) ◽  
pp. 738-741 ◽  
Author(s):  
R. S. Downing ◽  
T. K. Moilliet
Keyword(s):  
Panonychus Ulmi ◽  
Leaf Damage ◽  
Apple Trees ◽  
Phytoseiid Mites ◽  
External Structure ◽  
Phytophagous Mites ◽  
European Red Mite ◽  
Metaseiulus Occidentalis

AbstractIn two well-kept but nonsprayed orchards, the European red mite, Panonychus ulmi (Koch), was more numerous and caused more leaf damage to Delicious than to Spartan or McIntosh apple trees. The predacious phytoseiid mites, Metaseiulus occidentalis (Nesbitt) and Neoseiulus caudiglans (Schuster), were more numerous on both Spartan and McIntosh than on Delicious. The differences in the external structure of the leaves may be the reason for the greater abundance of phytoseiids on Spartan and McIntosh.

Sign in / Sign up

Export Citation Format

Share Document