Influence of Typhlodromus (T.) pyri Scheuten on the Development of Bryobia arborea M. & A. Populations in the Greenhouse

1962 ◽  
Vol 94 (8) ◽  
pp. 870-873 ◽  
Author(s):  
H. J. Herbert
Keyword(s):  
Nova Scotia ◽  
Commercial Production ◽  
Apple Orchards ◽  
Predacious Mites ◽  
Apple Trees

The brown mite, Bryobia arborea M. and A., is a widely distributed phytophagous pest of apple trees in Nova Scotia. Many predators have been observed feeding on this pest, particularly the predacious mites of the sub-family Phytoseiinae. It is difficult to assess the influence of these predators on brown mite in the field because fungicides, which are necessary in the commercial production of apples in Nova Scotia, often disrupt the relationships. Furthermore, other species of predators and prey usually found in apple orchards obscure the influence of phytoseiids on brown mite.

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 Influence of Spray Programs on the Fauna of Apple Orchards in Nova Scotia. III. Mites and their Predators

1949 ◽  
Vol 81 (8) ◽  
pp. 202-214 ◽  
Author(s):  
F. T. Lord
Keyword(s):  
Nova Scotia ◽  
Agricultural Production ◽  
Chemical Control ◽  
Commercial Production ◽  
Turn Of The Century ◽  
Control Measures ◽  
Apple Orchards

The commercial production of apples has led growers to greater reliance on chemical control measures for pests than have most fields of agricultural production. Since the turn of the century orchardists have plunged deeper and deeper into artificial measures to produce fruit free from blemishes without greatly alleviating the over-all pest problem and, in some cases, actually producing conditions conducive to still greater problems.

The Influence of Spray Programs on the Fauna of Apple Orchards in Nova Scotia. VII. Effects on Some Beneficial Arthropods

1954 ◽  
Vol 86 (3) ◽  
pp. 128-135 ◽  
Author(s):  
A. W. MacPhee ◽  
K. H. Sanford
Keyword(s):  
Nova Scotia ◽  
Natural Enemies ◽  
Apple Orchards ◽  
Beneficial Arthropods ◽  
Population Densities ◽  
Apple Trees ◽  
Arthropod Pests

The toxicities of a large number of spray chemicals to arthropod pests are well known. In most instances, observations on the effects of such materials on natural enemies have beeen incidental to other studies, and little has been published on experiments designed to determine the direct toxicities of the chemicals to beneficial species. The effects of spray chemicals on the predators and parasites of the major pests of apple trees in Nova Scotia have been investigated as part of a broader project on the factors that influence population densities of orchard arthropods, as outlined by Pickett et al. (31).

THE INFLUENCE OF SPRAY PROGRAMS ON THE FAUNA OF APPLE ORCHARDS IN NOVA SCOTIA: XVII. EFFECTS ON SOME PREDACIOUS MITES

1967 ◽  
Vol 99 (2) ◽  
pp. 197-201 ◽  
Author(s):  
K. H. Sanford
Keyword(s):  
Nova Scotia ◽  
Typhlodromus Pyri ◽  
Apple Orchards ◽  
Predacious Mites ◽  
Amblyseius Fallacis ◽  
Phytoseiulus Macropilis

AbstractThe effects from treating populations of predacious mites with a number of spray chemicals are tabulated. The species include Phytoseiidae: Typhlodromus pyri Scheuten, T. rhenanus (Oudms.), Amblyseius fallacis (Garman), Phytoseiulus macropilis (Banks), Amblyseius finlandicus (Oudms.); and Raphignathidae: Mediolatta novae-scotiae Nes. The chemicals include fungicides, acaricides and insecticides.

Eggs and Oviposition Sites of Some Predacious Mirids on Apple Trees (Miridae: Hemiptera)

1964 ◽  
Vol 96 (9) ◽  
pp. 1185-1189 ◽  
Author(s):  
K. H. Sanford
Keyword(s):  
Nova Scotia ◽  
Apple Orchards ◽  
Apple Trees ◽  
Oviposition Sites

AbstractThe eggs and oviposition sites of six species of predatory mirids from Nova Scotia apple orchards are described. These species are Hyaliodes harti Knight, Atractotomus mali (Meyer), Deraeocoris fasciolus Knight, Diaphnidia pellucida Uhler, Blepharidopterus angulatus (Fall), and Pilophorus perplexus D. & S. The differences between the eggs of each species are great enough to identify them in situ.

Seasonal wound presence and susceptibility to Neonectria ditissima infection in New Zealand apple trees

2015 ◽  
Vol 68 ◽  
pp. 250-256 ◽  
Author(s):  
N.T. Amponsah ◽  
M. Walter R.M. Beresford ◽  
R.W.A. Scheper
Keyword(s):  
New Zealand ◽  
Artificial Inoculation ◽  
Early Winter ◽  
Leaf Fall ◽  
Apple Orchards ◽  
Apple Trees ◽  
Leaf Scar ◽  
Fruit Thinning ◽  
Different Types

Leaf scar wounds are important sites for Neonectria ditissima infection of apple trees Monitoring leaf fall in Scilate/Envy and Braeburn trees to estimate leaf scar wound presence showed maximum leaf scar incidence occurred in June (early winter) Wounds detected in New Zealand apple orchards were bud scale scars fruit thinning and picking wounds leaf scars and pruning cuts Picking wounds are caused during harvest where the pedicel is detached from the shoot Susceptibility of these different types of wounds was determined using artificial inoculation of N ditissima conidia during the season Pruning cut wounds were the most susceptible followed by fruit picking and thinning wounds and the least susceptible were leaf scar wounds No infections were observed when bud scale wounds were inoculated There was no difference in wound susceptibility between cultivars but overall Scilate/Envy wounds developed more lesions than Braeburn wounds

The Brown Mite, Bryobia arborea Morgan and Anderson (Acarina: Tetranychidae), on Apple in Nova Scotia.: I. Influence of Intratree Distribution on the Selection of Sampling Units. II. Differences in Habits and Seasonal Trends in Orchards With Bivoltine and Trivoltine Populations. III. Distribution of Diapause Eggs. IV. Hatching of Diapause Eggs

1965 ◽  
Vol 97 (12) ◽  
pp. 1303-1318 ◽  
Author(s):  
H. J. Herbert
Keyword(s):  
Nova Scotia ◽  
First Generation ◽  
Second Generation ◽  
Central Area ◽  
Third Generation ◽  
Apple Trees ◽  
Seasonal Trends ◽  
Sample Unit ◽  
The Third ◽  
Selection Of

AbstractIn Nova Scotia one leaf cluster with an adjoining 1 inch of twig taken from the inside of each of 10 apple trees replicated four times is an adequate sample unit to measure the density of the brown mite.The brown mite has one generation with a partial second in some orchards and one with a partial second and partial third in others. The first generation adults in the bivoltine and trivoltine populations lay summer eggs on the leaves and twigs, and diapause eggs on tin twigs. The second generation adults in the bivoltine populations lay only diapause eggs; in the trivoltine populations they lay both summer and diapause eggs. The adults of the third generation lay only diapause eggs.The brown mite is found on both the leaves and woody parts of the tree. In orchards with bivoltine populations the proportion of mites on leaves reached a peak of 80% by mid-July, but thereafter gradually decreased to 10% by the end of August. However, in orchards with trivoltine populations the proportion of mites on leaves reached a peak of 80 to 90% by mid-July, remained constant until mid-August, and thereafter decreased to approximately 40% by the end of August.The number of diapause eggs laid by adults of each generation in both the bivoltine and trivoltine populations varies widely. The eggs are deposited on the trunk as well as on the branches, with the heaviest deposition in the central area of the tree. The diapause eggs laid by adults of the first generation are the last to hatch and those laid by the third generation are the first to hatch the following spring.The factors responsible for the differences in the number of generations and in the number of diapause eggs laid are unknown.

scholarly journals Gradient Boosting Estimation of the Leaf Area Index of Apple Orchards in UAV Remote Sensing

2021 ◽  
Vol 13 (16) ◽  
pp. 3263
Author(s):  
Zhijie Liu ◽  
Pengju Guo ◽  
Heng Liu ◽  
Pan Fan ◽  
Pengzong Zeng ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Leaf Area Index ◽  
Leaf Area ◽  
Shaanxi Province ◽  
Gradient Boosting ◽  
Support Vector ◽  
Apple Orchards ◽  
Apple Trees ◽  
Area Index ◽  
Spatial Efficiency

The leaf area index (LAI) is a key parameter for describing the canopy structure of apple trees. This index is also employed in evaluating the amount of pesticide sprayed per unit volume of apple trees. Hence, numerous manual and automatic methods have been explored for LAI estimation. In this work, the leaf area indices for different types of apple trees are obtained in terms of multispectral remote-sensing data collected with an unmanned aerial vehicle (UAV), along with simultaneous measurements of apple orchards. The proposed approach was tested on apple trees of the “Fuji”, “Golden Delicious”, and “Ruixue” types, which were planted in the Apple Experimental Station of the Northwest Agriculture and Forestry University in Baishui County, Shaanxi Province, China. Five vegetation indices of strong correlation with the apple leaf area index were selected and used to train models of support vector regression (SVR) and gradient-boosting decision trees (GBDT) for predicting the leaf area index of apple trees. The best model was selected based on the metrics of the coefficient of determination (R2) and the root-mean-square error (RMSE). The experimental results showed that the gradient-boosting decision tree model achieved the best performance with an R2 of 0.846, an RMSE of 0.356, and a spatial efficiency (SPAEF) of 0.57. This demonstrates the feasibility of our approach for fast and accurate remote-sensing-based estimation of the leaf area index of apple trees.

SOME ASPECTS OF A RYANIA-GLYODIN SPRAY SCHEDULE IN BRITISH COLUMBIA APPLE ORCHARDS: I. ENTOMOLOGICAL, HORTICULTURAL, AND ECONOMIC ASPECTS

1957 ◽  
Vol 37 (4) ◽  
pp. 423-433 ◽  
Author(s):  
C. V. G. Morgan ◽  
N. H. Anderson
Keyword(s):  
Detrimental Effect ◽  
Codling Moth ◽  
Economic Aspects ◽  
Apple Orchards ◽  
Predacious Mites ◽  
Eriosoma Lanigerum ◽  
Woolly Apple Aphid ◽  
Aphis Pomi ◽  
Lime Sulphur ◽  
Modified Schedule

In apple orchards at Summerland, B.C., four applications of 100 per cent ryania at 48 lb. per acre per application, with glyodin as the fungicide, gave control of light infestations of the codling moth, Carpocapsa pomonella (L.), similar to that from four sprays of 50 per cent DDT at 12 lb. per acre, with lime-sulphur, ferbam, and wettable sulphur. In a heavily-infested orchard, ryania was inferior to DDT. The ryania-glyodin schedule also controlled the woolly apple aphid, Eriosoma lanigerum (Hausm.), and the apple aphid, Aphis pomi DeG. It had little detrimental effect on predacious mites. Except for the apple rust mite, Vasates schlechtendali (Nal.), phytophagous mites were usually not so troublesome where the modified schedule was used.Packing-house records showed that the ryania-glyodin schedule reduced the size and lowered the grade of McIntosh, Newtown, and Delicious apples, and reduced the size of Red Delicious. Grade of Red Delicious was better with the modified than with the standard schedule. The 1954 applications of the modified schedule evidently reduced the size of the 1955 crops on all varieties; most seriously affected were McIntosh with 76.2 per cent reduction and Delicious with 53.7 per cent.

The Influence of Spray Programs on the Fauna of Apple Orchards in Nova Scotia. XIV.: Supplement to II. Oystershell Scale, Lepidosaphes ulmi (L.)

1965 ◽  
Vol 97 (8) ◽  
pp. 816-821 ◽  
Author(s):  
A. D. Pickett
Keyword(s):  
Nova Scotia ◽  
Apple Orchards ◽  
Key Factors ◽  
Predacious Mite ◽  
Winter Temperatures

AbstractThis study confirms an earlier finding that the oystershell scale, Lepidosaphes ulmi (L.) is normally controlled in Nova Scotia apple orchards by the aphelinid Aphytis mytilaspidis Le B. and the predacious mite Hemisarcoptes malus (Shimer). The effectiveness of the former may be limited in colder areas by low winter temperatures, and both species are detrimentally affected by some spray chemicals. The evidence presented indicates that either A. mytilaspidis, or H. malus, or the two of them together, may operate as key-factors in regulating the density of oystershell scale populations.

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