AN APPRAISAL OF METHODS OF SAMPLING APPLE TREES AND RESULTS OF SOME TESTS USING A SAMPLING UNIT COMMON TO INSECT PREDATORS AND THEIR PREY

1968 ◽  
Vol 100 (1) ◽  
pp. 23-33 ◽  
Author(s):  
F. T. Lord
Keyword(s):  
Total Population ◽  
Prey Species ◽  
Panonychus Ulmi ◽  
Sampling Unit ◽  
Important Criterion ◽  
Apple Trees ◽  
Common Basis ◽  
Quantitative Manner ◽  
Insect Predators ◽  
Whole Tree

AbstractCurrent methods of sampling predator and prey populations on apple trees use two different indexes to measure the comparative abundance of each. Techniques are sought that relate the proportions of one to the other in the sampling universe (the orchard) in a quantitative manner. The most important criterion is that the sampling unit be one common to both predator and prey species and encompass representative portions of the habitat of each. The whole tree meets this criterion but it is too cumbersome to sample in toto. The large limb was, therefore, appraised for feasibility as a basic sampling unit common to many species. All clusters were counted and the predators and prey expressed as numbers per 100 clusters. The whole limb was examined for insect predators but only a representative portion of it was used in estimating mite populations. The test prey species was the European red mite, Panonychus ulmi (Koch), and the predators a small number of active insect species, mostly Diaphnocoris pellucida (Uhler) and Anthocoris musculus (Say). It was found that the numbers of mites on randomly chosen clusters from a limb were representative of the total population of mites on a limb but the associated variation was high. Samples of relatively uniform (standard) clusters of good vigour overestimated the mite population. Some other causes of variation were also examined and are discussed. A 2-year orchard test showed it was feasible to estimate the abundance of both mites and predators on a common basis and thus obtain a measure of the ratio of mites to predators in the sampling universe.

Effects of phytoseiid predators on the sex ratio of the spider mite Panonychus ulmi

1991 ◽  
Vol 69 (1) ◽  
pp. 208-212 ◽  
Author(s):  
Dan L. Johnson ◽  
Heather C. Proctor
Keyword(s):  
Population Density ◽  
Sex Ratio ◽  
Spider Mite ◽  
Total Population ◽  
Panonychus Ulmi ◽  
Encounter Rate ◽  
Male Mortality ◽  
Adult Sex Ratio ◽  
Biased Sex Ratio ◽  
Male Activity

The effect of predator presence on the adult sex ratio of a spider mite (Panonychus ulmi) was examined in a field experiment. Phytoseiid predators (chiefly Typhlodromus occidentalis) were removed from 32 trees harboring P. ulmi populations, and allowed to remain at natural levels on 32 other trees. Both total population density and proportion of males in the prey population were significantly higher in predator-free trees. Mechanisms that could explain the increase in the proportion of males are examined. The most probable is that greater male activity results in a higher encounter rate between predator and prey, and that subsequent higher male mortality when predators are present exaggerates the female-biased sex ratio. The theoretical effects of sex-biased predation on diplo-diploid and haplo-diploid organisms are discussed.

scholarly journals Occupancy estimation of jaguar Panthera onca to assess the value of east-central Mexico as a jaguar corridor

Oryx ◽  
2013 ◽  
Vol 48 (1) ◽  
pp. 133-140 ◽  
Author(s):  
Lisanne S. Petracca ◽  
O. Eric Ramírez-Bravo ◽  
Lorna Hernández-Santín
Keyword(s):  
Large Scale ◽  
Prey Species ◽  
Landscape Connectivity ◽  
Site Occupancy ◽  
Sampling Unit ◽  
Eastern Coast ◽  
Panthera Onca ◽  
Occupancy Modelling ◽  
Pecari Tajacu ◽  
Collared Peccary

AbstractThe use of wildlife corridors to maintain landscape connectivity has become increasingly relevant to the conservation of wide-ranging species, including the jaguar Panthera onca. Jaguars are particularly threatened in Mexico, where corridor linkages are tenuous as a result of habitat fragmentation. Our study assessed a section of potential corridor south of the Sierra Madre Oriental in eastern Mexico. We conducted 245 interviews with local inhabitants in 140 36-km2 sampling units over a 5-month period and compiled detection histories for jaguars and five prey species: collared peccary Pecari tajacu, red brocket deer Mazama americana, white-tailed deer Odocoileus virginianus, spotted paca Agouti paca, and nine-banded armadillo Dasypus novemcinctus. These detection histories were then analysed using site occupancy modelling. Each sampling unit was assigned a probability of habitat use based on (1) the two smaller prey species (paca and armadillo) and (2) at least two of the larger prey species (collared peccary and two deer species) using habitat in that unit. This probability estimate was considered a proxy for the prey base of each sampling unit and therefore the unit's suitability as a jaguar corridor. Although the prey base in some areas appears adequate to support a jaguar population, large-scale development projects and the paucity of jaguar sign are major obstacles to this region's potential as a jaguar corridor. Our results suggest that the eastern coast of Mexico may not be a priority area for range-wide jaguar conservation.

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 EGGS AND OVIPOSITION SITES OF DIAPHNIDIA CAPITATA (HEMIPTERA: MIRIDAE) ON APPLE TREES

1970 ◽  
Vol 102 (10) ◽  
pp. 1316-1319 ◽  
Author(s):  
R. L. Horsburgh ◽  
Dean Asquith
Keyword(s):  
Tetranychus Urticae ◽  
Spider Mites ◽  
Panonychus Ulmi ◽  
Apple Trees ◽  
Oviposition Sites

AbstractNymphal and adult Diaphnidia capitata (Van Duzee) have long been recognized as predators of Panonychus ulmi (Koch) and Tetranychus urticae Koch. The eggs and oviposition sites preferred by this species are described herein to supplement available descriptions of the eggs of mirid predators of spider mites.

DISTRIBUTION OF PHYTOPHAGOUS AND PREDACIOUS MITES ON APPLE TREES IN NOVA SCOTIA

1973 ◽  
Vol 105 (2) ◽  
pp. 271-276 ◽  
Author(s):  
H. J. Herbert ◽  
K. P. Butler
Keyword(s):  
Nova Scotia ◽  
Panonychus Ulmi ◽  
Predacious Mites ◽  
Apple Trees ◽  
Predacious Mite ◽  
Phytophagous Mites ◽  
Lower Position ◽  
Zetzellia Mali ◽  
Aculus Schlechtendali ◽  
Mature Apple

AbstractThe relative densities of phytophagous and predacious mites within mature apple trees were examined. The eggs of phytophagous mites Aculus schlechtendali (Nal.) and Panonychus ulmi (Koch) were more numerous in the lower position of the tree while the reverse was true for the predacious mite Zetzellia mali (Ewing) and its eggs.

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).

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.

LABORATORY TESTS TO COMPARE THE PREDATORY VALUE OF SIX MIRID SPECIES IN EACH STAGE OF DEVELOPMENT AGAINST THE WINTER EGGS OF THE EUROPEAN RED MITE, PANONYCHUS ULMI (ACARI: TETRANYCHIDAE)

1971 ◽  
Vol 103 (12) ◽  
pp. 1663-1669 ◽  
Author(s):  
F. T. Lord
Keyword(s):  
Laboratory Tests ◽  
Prey Species ◽  
Panonychus Ulmi ◽  
Sources Of Information ◽  
Laboratory Rearing ◽  
Stage Of Development ◽  
European Red Mite ◽  
Campylomma Verbasci ◽  
Predacious Species ◽  
Feeding Techniques

AbstractSix species of predacious Miridae, common to apple trees in Nova Scotia, were used to develop laboratory rearing and feeding techniques for comparing the abilities of predators to consume prey. The test prey species was the European red mite, Panonychus ulmi (Koch), in the winter egg stage. The numbers of eggs consumed per day and per instar in the tests compared favourably with the known predatory values of these mirids under orchard conditions. Both sources of information were used to give the predators a tentative rating. The mirids Hyaliodes harti Knight, Diaphnocoris pellucida (Uhler), Pilophorus perplexus D. and S., and Blepharidopterus angulatus (Fall.) are effective predators, approximately equal to each other in ability to consume the winter eggs of the red mite. The two species Campylomma verbasci (Meyer) and Atractotomus mali (Meyer), which are phytophagous as well as predacious, were less voracious.The results indicate it may be feasible to develop a series of weighting factors, one for each stage of each predacious species, based on ability to consume prey.

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