Mating Suppression of Caged Spruce Budworm (Lepidoptera: Tortricidae) Moths in Different Pheromone Atmospheres and High Population Densities

1982 ◽  
Vol 75 (6) ◽  
pp. 989-993 ◽  
Author(s):  
P. Palaniswamy ◽  
R. J. Ross ◽  
W. D. Seabrook ◽  
G. C. Lonergan ◽  
C. J. Wiesner ◽  
...  
Keyword(s):  
Spruce Budworm ◽  
High Population ◽  
Population Densities

A LARGE-CAPACITY PHEROMONE TRAP FOR SPRUCE BUDWORM MOTHS (LEPIDOPTERA: TORTRICIDAE),

1982 ◽  
Vol 114 (5) ◽  
pp. 461-463 ◽  
Author(s):  
David M. Kendall ◽  
Daniel T. Jennings ◽  
Mark W. Houseweart
Keyword(s):  
Choristoneura Fumiferana ◽  
Spruce Budworm ◽  
Pheromone Trap ◽  
High Population ◽  
Pheromone Traps ◽  
Population Densities ◽  
Large Capacity ◽  
Baited Traps ◽  
Moth Scales

Several types of pheromone-baited traps have been used for trapping males of the spruce budworm, Choristoneura fumiferana (Clem.). Most pheromone traps have sticky surfaces for capturing attracted moths; however, the sticky surface often becomes saturated with moths, moth scales, and debris, thus diminishing the traps' effectiveness. At high population densities, saturation may occur within a few hours after the traps are placed in the field. The Pherocon 1CP® trap found most effective by Sanders (1978) functionally saturates after about 50 spruce budworm moths are caught (Houseweart et al. 1981).

LONG TERM STUDY OF THE EFFECTIVENESS OF AERIAL APPLICATION OF BACILLUS THURINGIENSIS – ACEPHATE COMBINATIONS AGAINST THE SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (LEPIDOPTERA: TORTRICIDAE)

1977 ◽  
Vol 109 (9) ◽  
pp. 1239-1248 ◽  
Author(s):  
O. N. Morris
Keyword(s):  
Bacillus Thuringiensis ◽  
Choristoneura Fumiferana ◽  
Larval Mortality ◽  
Abies Balsamea ◽  
Spruce Budworm ◽  
White Spruce ◽  
Balsam Fir ◽  
Population Densities ◽  
Long Term Study

AbstractBacillus thuringiensis (Dipel® 36B) mixed with a sublethal concentration of acephate (Orthene®) (O, S-dimethyl acetylphosphoramidothioate), an organophosphorous insecticide, was applied at 2.35–14 l./ha to white spruce (Picea glauca) and balsam fir (Abies balsamea) trees infested with spruce budworm, Choristoneura fumiferana (Clem.). The treatment rate was 20 Billion International Units of B. thuringiensis (B.t.) activity with or without 42 g of active ingredient of acephate/ha.The ground deposit of the standard Dipel wettable powder formulation was 12% of emitted volume compared with 21–32% for the Dipel 36B flowable. The viability of B.t. spores was drastically reduced after 1 day of weathering but a high level of biological activity by the spore–crystal complex persisted for up to 20 days post-spray due probably to crystal activity.The addition of about 10% of the recommended operational rate of acephate to the B.t. suspension increased larval mortality by 34% when applied at 4.7 l./ha. Reductions in budworm populations were 97–99% in B.t. + acephate plots and 86–90% in B.t. alone plots.Plots with moderate budworm densities of up to 27 larvae/100 buds on white spruce and 36/100 on balsam fir were satisfactorily protected from excessive defoliation in the year of spray by B.t. with or without acephate. Plots with higher population densities were not satisfactorily protected based on the branch sample examination but aerial color photographs indicated good protection to the top third of the trees. Population declines were greater and defoliation and oviposition were lower in the treated plots than in the untreated checks 1 year later without further treatment. Two years later the larval population densities in all plots were low but the density was twice as high in the untreated check as in the treated plots, indicating long term suppression by the treatments. Defoliation was negligible in all plots.The treatments had no deleterious effect on spruce budworm parasitism. The data indicate that the integrated approach using Bacillus thuringiensis – chemical pesticide combinations is a viable alternative to the use of chemical pesticides alone in spruce budworm control. Large scale testing is now warranted.

Maternal Inhibition of Hatching at High Population Densities inTigriopus japonicus(Copepoda, Crustacea)

1988 ◽  
Vol 174 (2) ◽  
pp. 139-144 ◽  
Author(s):  
DAVID KAHAN ◽  
YEHUDA BERMAN ◽  
THEODORA BAR-EL
Keyword(s):  
High Population ◽  
Population Densities

scholarly journals The significance of biomass allocation to population growth of the invasive species Ambrosia artemisiifolia and Ambrosia trifida with different densities

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Wenxuan Zhao ◽  
Tong Liu ◽  
Yan Liu ◽  
Hanyue Wang ◽  
Ruili Wang ◽  
...  
Keyword(s):  
Cluster Formation ◽  
Ambrosia Artemisiifolia ◽  
High Density ◽  
High Population ◽  
Leaf Biomass ◽  
Total Biomass ◽  
Low Density ◽  
Population Densities ◽  
Ambrosia Trifida ◽  
Short Period

Abstract Background Ambrosia artemisiifolia and Ambrosia trifida are globally distributed harmful and invasive weeds. High density clusters play an important role in their invasion. For these two species, the early settled populations are distributed at low densities, but they can rapidly achieve high population densities in a short period of time. However, their response to intraspecific competition to improve the fitness for rapid growth and maintenance of high population densities remains unclear. Therefore, to determine how these species form and maintain high population densities, individual biomass allocations patterns between different population densities (low and high), and plasticity during seedling, vegetative, breeding and mature stages were compared. In 2019, we harvested seeds at different population densities and compared them, and in 2020, we compared the number of regenerated plants across the two population densities. Results Most biomass was invested in the stems of both species. Ambrosia trifida had the highest stem biomass distribution, of up to 78%, and the phenotypic plasticity of the stem was the highest. Path analysis demonstrated that at low-density, total biomass was the biggest contributor to seed production, but stem and leaf biomass was the biggest contributors to high-density populations. The number of seeds produced per plant was high in low-density populations, while the seed number per unit area was huge in high-density populations. In the second year, the number of low-density populations increased significantly. A. artemisiifolia and A. trifida accounted for 75.6% and 68.4% of the mature populations, respectively. Conclusions High input to the stem is an important means to regulate the growth of the two species to cope with different densities. These two species can ensure reproductive success and produce appropriate seed numbers. Therefore, they can maintain a stable population over time and quickly form cluster advantages. In the management, early detection of both species and prevention of successful reproduction by chemical and mechanical means are necessary to stop cluster formation and spread.

High population densities of Macrolophus pygmaeus on tomato plants can cause economic fruit damage: interaction with Pepino mosaic virus ?

2015 ◽  
Vol 72 (7) ◽  
pp. 1350-1358 ◽  
Author(s):  
Rob Moerkens ◽  
Els Berckmoes ◽  
Veerle Van Damme ◽  
Nelia Ortega-Parra ◽  
Inge Hanssen ◽  
...  
Keyword(s):  
Mosaic Virus ◽  
High Population ◽  
Population Densities ◽  
Pepino Mosaic Virus ◽  
Tomato Plants ◽  
Macrolophus Pygmaeus ◽  
Fruit Damage

Life Cycle of Carpophilus humeralis F. (Coleoptera: Nitidulidae) in Puerto Rico

1969 ◽  
Vol 68 (1) ◽  
pp. 53-57
Author(s):  
Fernando Gallardo-Covas
Keyword(s):  
Puerto Rico ◽  
Life Cycle ◽  
Reproductive Potential ◽  
Larval Period ◽  
High Population ◽  
Population Densities ◽  
Ripe Fruit ◽  
Laboratory Conditions ◽  
Carpophilus Humeralis

Carpophilus humeralis F. is one of the main pests on pineapple in Puerto Rico. This insect has high population densities because of a high reproductive potential, each female under laboratory conditions, lays about 542 eggs over a two month period, averaging 9 eggs per day; short larval period (18 days); longevity of adults (2.5 months); and abundance of ripe fruit in pineapple fields as sites for constant reproduction.

scholarly journals Neolithic Priorities: Ritual and Visual Preferences within Burials and Corporeality in the Balkans

2014 ◽  
Vol 17 (2) ◽  
pp. 184-207
Author(s):  
Goce Naumov
Keyword(s):  
Case Studies ◽  
Social Hierarchy ◽  
High Population ◽  
Body Parts ◽  
Population Densities ◽  
Funerary Practices ◽  
The Balkans ◽  
Select Group ◽  
Visual Preferences ◽  
Geographical Context

Neolithic bodies are not only manifestations of subjective principles. Social and symbolic norms are also incorporated within the bodies of both actual and represented individuals. These norms often relate to economic and religious notions of society, as well as to effigies. Owing to high population densities in Neolithic villages, only a select group of the inhabitants were buried within settlements or represented in images. This generated a category of privileged individuals and body features, which were related to symbolic principles rather than social hierarchy. Such practices among Neolithic societies in the Balkans are evident within burials and human representations. Individuals buried inside settlements, anthropomorphic house models, and figurines from several sites in Ovče Pole, Pelagonia, and the Skopje Valley are used as case studies in this paper. Placing these sites into a wider geographical context, it is argued that gender, age and body parts were significant criteria in funerary practices and features of corporeality.

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