LIMITS OF EACH STAGE IN POPULATIONS OF THE EUROPEAN RED MITE, PANONYCHUS ULMI

1970 ◽  
Vol 102 (1) ◽  
pp. 64-68 ◽  
Author(s):  
H. J. Herbert

AbstractField populations of the European red mite, Panonychus ulmi (Koch), in Nova Scotia were separated into eggs, larvae, protonymphs, deutonymphs, and adults and the length of time each stage was present for each generation was determined in 1967 and 1968. The duration of each generation was similar in both years, although the diapause eggs hatched later in 1967 than in the succeeding year. Detailed information on the seasonal history is necessary in assessing red mite mortality and in timing of chemical controls of this pest.

1973 ◽  
Vol 105 (12) ◽  
pp. 1519-1523 ◽  
Author(s):  
H. J. Herbert ◽  
K. P. Butler

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.


1970 ◽  
Vol 102 (5) ◽  
pp. 592-601 ◽  
Author(s):  
K. H. Sanford ◽  
H. J. Herbert

AbstractUtilizing the knowledge of their direct effects, the materials ryania, carbaryl, and Animert V-101 applied to a uniformly distributed population of the European red mite, Panonychus ulmi (Koch), altered the populations in plots in an apple orchard. Trends after treatment in both host mite and predator populations were assessed. Supplementary applications of the acaricides Animert V-101 or dicofol directed against certain generations of P. ulmi controlled outbreaks and altered the faunal levels during the following season. Ryania was largely innocuous to most species of predators with the exception of Atractotomus mali (Meyer) and Diaphnocoris spp., carbaryl was detrimental to most predacious species, and Animert V-101, while selectively toxic to phytophagous mites, was innocuous to all predacious insects and Typhlodromus pyri Scheuten.Phytophagous mite populations may be altered to almost prescribed levels with pesticides when the predator populations are known. This allows selective chemicals to be used to complement the predator effect and maintain red mites below the threshold of damage.


1961 ◽  
Vol 93 (10) ◽  
pp. 924-927 ◽  
Author(s):  
F. T. Lord ◽  
D. K. R. Stewart

Prior to 1950 the European red mite, Panonychus ulmi Koch, was a major pest in Nova Scotia apple orchards, and brown mite, Bryobia arborea M. and A., was practically non-existent. Lord (1949), showed that the sulphur fungicides, commonly in use up to that time, were detrimental to some of the predacious species and toxic to the brown mite. After 1950 red mite populations became negligible and, although the brown mites increased, they did not become sufficiently abundant to cause economic damage. This shift of population balance in Nova kotia orchards has been attributed to the gradual replacement of sulphur and other detrimental materials by pesticides less harmful to predators of the mites (Pickett 1953).


1982 ◽  
Vol 114 (8) ◽  
pp. 703-712 ◽  
Author(s):  
H. J. Herbert ◽  
K. B. McRae

AbstractEclosion of overwintering eggs of the European red mite, Panonychus ulmi (Koch), in Nova Scotia was studied at four constant temperatures. Days to 50% hatch were 44.8, 23.1, 12.9, and 8.8 while the rates of development were 2.18, 4.53, 7.59, and 11.34% per day at 8°, 12°, 16 °and 20 °C, respectively. Nonlinear equations were developed to estimate the time to 50% hatch of overwintering eggs as a function of temperature. A weighted average of the daily extreme temperatures was used to improve the estimated time to 50% hatch for field data from the rates of development in the constant temperature studies.


1975 ◽  
Vol 107 (8) ◽  
pp. 801-806 ◽  
Author(s):  
D. C. Herne ◽  
Mikio Chiba

AbstractMortality of the European red mite, Panonychus ulmi (Koch), on peach leaves was directly related to the uniformity of distribution and amount of deposit of dicofol for up to 4 days after the spray was applied. Mite mortality decreased rapidly from the 4th to the 11th day after spraying, whereas the dicofol detected by chemical analysis decreased at a slower rate. The minimum deposit of dicofol for 100% kill of the mite, immediately after spraying, was between 0.3 and 0.8 μg/cm2, depending upon uniformity of coverage. Doubling the dose did not increase the mortality then or later. Fourteen days after spraying, the dicofol deposit on some leaves was still 0.7–0.8 μg/cm2 but there was practically no mite mortality.


1975 ◽  
Vol 107 (8) ◽  
pp. 825-828 ◽  
Author(s):  
H. J. Herbert ◽  
K. P. Butler

AbstractThe number of male and female first generation Panonychus ulmi (Koch) were recorded from 13 apple orchards representing widely different levels of mite infestation on four different varieties. The average percentage of males was 27.5. Statistically significant differences were found among orchards, varieties, observers, and their interactions. No relationship between sex ratio and population density was evident.


1969 ◽  
Vol 101 (1) ◽  
pp. 62-67 ◽  
Author(s):  
H. J. Herbert ◽  
K. H. Sanford

AbstractMaintenance of predacious arthropods in apple orchards requires both the judicious use of chemical sprays and the presence of adequate food supplies. When the common food source, the European red mite, Panonychus ulmi (Koch), is depleted by either a selective chemical, such as Animert V-101, or by excessive activity of the predators, the apple rust mite, Vasates schlechtendali (Nal.), if present, provides an alternate food. This enables survival of sufficient numbers of predators to prevent resurgence of the red mite within the same season.


1935 ◽  
Vol 13d (2) ◽  
pp. 19-39 ◽  
Author(s):  
F. C. Gilliatt

Predators are the most important natural enemies of the European red mite. Notes are given on the life history and habits of the following predaceous enemies of this mite, Seiulus pomi Parrott; Diaphnidia pellucida Uhl.; Diaphnidia capitata Van D.; Hyaliodes vitripennis Say; Stethorus punctum Leconte; Plagiognathus obscurus Uhl.; Camptobrochis nebulosus Uhl.; Anystis agilis Banks; Campylomma verbasci Mey., and an unidentified species of Syrphidae.


Biotemas ◽  
2017 ◽  
Vol 30 (1) ◽  
pp. 73
Author(s):  
Cláudia Andréia Gräff ◽  
Liana Johann ◽  
Cláucia Fernanda Volken de Souza ◽  
Noeli Juarez Ferla

http://dx.doi.org/10.5007/2175-7925.2017v30n1p73A vitivinicultura no estado do Rio Grande do Sul tem sofrido infestações significativas de ácaros praga, destacando-se recentemente Panonychus ulmi (Koch). Há relatos sobre a capacidade de controle de ácaros fitófagos com Isaria fumosorosea. O objetivo deste trabalho foi avaliar em laboratório a ação patogênica de I. fumosorosea sobre o ácaro P. ulmi. As criações de P. ulmi foram estabelecidas a partir de coleta realizadas em videiras da Serra Gaúcha. Sobre os ovos de P. ulmi, as aplicações de suspensões de esporos foram feitas em diferentes concentrações. As triplicatas das fêmeas de 12 a 15 dias foram tratadas com suspensão a 108 esporos x mL-1. As testemunhas foram tratadas com água destilada. Após sete dias da aplicação, observaram-se 55,6% de ovos não eclodidos tratados com suspensão 106 esporos x mL-1 e com fêmeas tratadas obteve-se uma mortalidade total entre 85-90% e mortalidade confirmada entre 50-55%. A mortalidade máxima dos controles no tratamento dos ovos e das fêmeas foi, em média, de 12,8 e 15,5%, respectivamente. Conclui-se que o isolado I. fumosorosea possui habilidade para infectar ovos e fêmeas adultas de P. ulmi e portanto mostra-se como uma alternativa viável para ser experimentada no campo.


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