The Biology of a Hyperparasite, Euceros frigidus Cress. (Ichneumonidae) and Description of the Planidial Stage

1961 ◽  
Vol 93 (1) ◽  
pp. 40-58 ◽  
Author(s):  
Howard A. Tripp
Keyword(s):  
Pinus Banksiana ◽  
Jack Pine ◽  
Life Cycles ◽  
Sufficient Information ◽  
Immature Stages ◽  
Primary Object ◽  
Forest Biology ◽  
Biology Laboratory ◽  
Overall Mortality

For more than a decade the sawfly, Neodiprion swainei Midd., has been a serious defoliator of jack pine, Pinus banksiana Lamb., in the Province of Quebec. In 1955 an intensive research program involving several research officers was initiated at the Forest Biology Laboratory, Quebec, to study the insect. Investigations began near the centre of the infestation at the headwaters of the Gatineau River (47° 55′N., 75° 25′W.). The project dealing with the parasites became the responsibility of the author and constituted approximately 25 pcr cent of the total investigations. Integrated with this project were studies on population dynamics, effect of defoliation on jack pine, and predators of the sawfly with emphasis on the small mammals. The primary object of the parasite studies was to concentrate on the life cycles and descriptions of the immature stages and to publish on each species as sufficient information was obtained. Ultimately, it is planned to publish jointly with other members of the team on the role of parasites in the overall mortality complex of Neodiprion swainei.

The Relationship of Spathimeigenia spinigera Townsend (Diptera: Tachinidae) to its Host, Neodiprion swainei Midd. (Hymenoptera: Diprionidae)

1962 ◽  
Vol 94 (8) ◽  
pp. 809-818 ◽  
Author(s):  
H. A. Tripp
Keyword(s):  
Population Dynamics ◽  
Pinus Banksiana ◽  
Jack Pine ◽  
Immature Stages ◽  
Pine Sawfly ◽  
Factors Influencing ◽  
Form Part ◽  
Extensive Program ◽  
Relationship Of ◽  
The Relationship

Studies on the parasites of the Swaine jack pine sawfly, Neodiprion swainei Midd., form part of an extensive program designed to assess the factors influencing population dynamics of this important defoliator of jack pine, Pinus banksiana Lamb. Investigations were carried out in the Province of Quebec between 1955 and 1959 near the headwaters of the Gatineau River, Abitibi County, and continued during 1960 and 1961 near the source of the Vermillion River, County Laviolette. In both areas, one of the principal parasites associated with N. swainei was the tachinid, Spathimeigenia spinigera Townsend. Descriptions of the immature stages of this parasite, and details of its behaviour were published previously (Tripp, 1960).

The role of wound periderm in the resistance of eastern larch and jack pine to dwarf mistletoe

1971 ◽  
Vol 49 (4) ◽  
pp. 501-504 ◽  
Author(s):  
F. H. Tainter ◽  
D. W. French
Keyword(s):  
Pinus Banksiana ◽  
Jack Pine ◽  
Larix Laricina ◽  
Dwarf Mistletoe ◽  
Resistance Reaction ◽  
Relative Scarcity

Formation of wound periderm appears to be a common form of resistance reaction in the Arceuthobium pusillum – Larix laricina combination, based on previous observations and an extensive examination of two witches' brooms of this host. Not only is wound periderm common in spur shoots within witches' brooms, but it also apparently restricts the development of the endophytic system in branchlets composing witches' brooms. Branchlets within witches' brooms of Pinus banksiana infected with A. pusillum and A. americanum also produced wound periderm similar to that described in eastern larch, which may account for the relative scarcity of aerial shoots on this host and restricted development of the endophytic system.

Taxonomy of the Genus Cecidomyia (Diptera: Cecidomyiidae) with Special Reference to the Species Occurring on Pinus banksiana Lamb

1960 ◽  
Vol 92 (1) ◽  
pp. 65-79 ◽  
Author(s):  
J. R. Vockeroth
Keyword(s):  
North America ◽  
Special Reference ◽  
Pinus Banksiana ◽  
Jack Pine ◽  
Regional Research ◽  
Department Of Agriculture ◽  
The Past ◽  
Canada Department ◽  
Forest Biology ◽  
Subjective Synonym

Several species of resin midges (or pine-pitch midges) have been recorded from species of Pinus in North America. These are all at present referred to the genus Retinodiplosis Kieffer 1912; for reasons given below this genus is here treated as a subjective synonym of Cecidomyia Meigen 1803. At least two species of Cecidomyia have been recorded from jack pine, Pinus banksiana Lamb., in Ontario, Manitoba, Saskatchewan and Michigan (Bradlev (1946), Barker and Wong (1948), anonymous (1946), Prentice and Hildahl (1957, 1958) and Mc-Daniel (1938)); they were sometimes determined as Retinodiplosis sp., sometimes tentatively or definitely as R. resinicola (O.S.). Study of specimens of Cecidomyia from P. banksiana collected during the past three years by officers of the Forest Biology Regional Research Laboratories, Canada Department of Agriculture, has shown that three species of the genus occur on this host. All three are described as new in this paper. C. resinicola (O.S.) 1871, originally described from Virginia pine, Pinus virginiana Mill., was not present in this material nor among Michigan specimens from P. banksiana in the U.S.N.M.; it almost certainly does not occur on P. banksiana.

scholarly journals Waterlogging-Stress-Responsive LncRNAs, Their Regulatory Relationships with MiRNAs and Target Genes in Cucumber (Cucumis sativus L.)

2021 ◽  
Vol 22 (15) ◽  
pp. 8197
Author(s):  
Kinga Kęska ◽  
Michał Wojciech Szcześniak ◽  
Adela Adamus ◽  
Małgorzata Czernicka
Keyword(s):  
Target Genes ◽  
Recovery Period ◽  
Sufficient Information ◽  
Low Oxygen ◽  
Waterlogging Tolerance ◽  
Cucumis Sativus L ◽  
Waterlogging Stress ◽  
Non Coding Rna

Low oxygen level is a phenomenon often occurring during the cucumber cultivation period. Genes involved in adaptations to stress can be regulated by non-coding RNA. The aim was the identification of long non-coding RNAs (lncRNAs) involved in the response to long-term waterlogging stress in two cucumber haploid lines, i.e., DH2 (waterlogging tolerant—WL-T) and DH4 (waterlogging sensitive—WL-S). Plants, at the juvenile stage, were waterlogged for 7 days (non-primed, 1xH), and after a 14-day recovery period, plants were stressed again for another 7 days (primed, 2xH). Roots were collected for high-throughput RNA sequencing. Implementation of the bioinformatic pipeline made it possible to determine specific lncRNAs for non-primed and primed plants of both accessions, highlighting differential responses to hypoxia stress. In total, 3738 lncRNA molecules were identified. The highest number (1476) of unique lncRNAs was determined for non-primed WL-S plants. Seventy-one lncRNAs were depicted as potentially being involved in acquiring tolerance to hypoxia in cucumber. Understanding the mechanism of gene regulation under long-term waterlogging by lncRNAs and their interactions with miRNAs provides sufficient information in terms of adaptation to the oxygen deprivation in cucumber. To the best of our knowledge, this is the first report concerning the role of lncRNAs in the regulation of long-term waterlogging tolerance by priming application in cucumber.

The Role of Predation in Determining Traits of Aedes aegypti (Diptera: Culicidae) and Infection With Zika Virus

2021 ◽  
Author(s):  
Shawna Bellamy ◽  
Barry W Alto
Keyword(s):  
Aedes Aegypti ◽  
Zika Virus ◽  
Life History Traits ◽  
Immature Stages ◽  
Direct Effects ◽  
Infected Blood ◽  
Predator Prey ◽  
Susceptibility To Infection ◽  
Density Reduction

Abstract Non-lethal predator-prey interactions during the immature stages can cause significant changes to mosquito life history traits and their ability to transmit pathogens as adults. Treatment manipulations using mosquitoes Aedes aegypti (L.) and Toxoryhnchites rutilus (Coquillett) were performed during the immature stages to explore the potential impacts of non-lethal interactions on adult susceptibility to infection, disseminated infection and saliva infection of Ae. aegypti following ingestion of Zika virus-infected blood. Treatments inducing density reduction resulted in reduced development time and survivorship to adulthood. However, effects of treatment did not alter infection, dissemination, or saliva infection. These observations indicate that, while non-lethal predation may impact some traits that influence population dynamics and transmission of pathogens, there were no direct effects on mosquito-arbovirus interactions.

Health determinants in Canadian northern environmental impact assessment

Polar Record ◽  
2006 ◽  
Vol 42 (4) ◽  
pp. 315-324 ◽  
Author(s):  
Jackie Bronson ◽  
Bram F. Noble
Keyword(s):  
Decision Making ◽  
Environmental Impact ◽  
Impact Assessment ◽  
Environmental Impact Assessment ◽  
Health Impact ◽  
Life Cycles ◽  
Local Context ◽  
Health Determinants ◽  
Limited Attention

The need to address the human health implications of northern development is well founded, and the role of health determinants in environmental impact assessment is increasingly recognised; however, there is limited understanding of the nature of health determinants and current practices in northern project assessment and decision making. This paper reports on a study of the nature and use of health determinants in Canadian northern environmental impact assessment, and discusses the key challenges to, and opportunities for, improved practice. Four themes emerged from this study. First, the consideration of health is limited to physical environments and the physical determinants of health, with limited attention to broader social and cultural health determinants. Second, when health is considered in northern project impact assessments such considerations rarely carry forward to post-project approval monitoring of health determinants and evaluation of health impact management programmes. Third, while there is general consensus that health determinants should be an integral part of northern impact assessment, there exist different expectations of the role of health determinants in project evaluation and decision making due in large part to different understandings and interpretations of health. Finally, a broader conceptualisation of health and health determinants in northern environmental impact assessment is required; one that takes into consideration northern cultures and knowledge systems, and is adaptive to local context, geography and life cycles.

scholarly journals Trade-Offs among Release Treatments in Jack Pine Plantations: Twenty-Five Year Responses

Forests ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 370
Author(s):  
Holly D. Deighton ◽  
Frederick Wayne Bell ◽  
Nelson Thiffault ◽  
Eric B. Searle ◽  
Mathew Leitch ◽  
...  
Keyword(s):  
Plant Diversity ◽  
Boreal Forests ◽  
Pinus Banksiana ◽  
Vegetation Management ◽  
Jack Pine ◽  
Forest Diversity ◽  
Trade Offs ◽  
Jack Pine Forests ◽  
Stand Yield ◽  
Forest Managers

We assessed 27 indicators of plant diversity, stand yield and individual crop tree responses 25 years post-treatment to determine long-term trade-offs among conifer release treatments in boreal and sub-boreal forests. This research addresses the lack of longer-term data needed by forest managers to implement more integrated vegetation management programs, supporting more informed decisions about release treatment choice. Four treatments (untreated control, motor-manual brushsaw, single aerial spray, and complete competition removal) were established at two jack pine (Pinus banksiana Lamb.) sites in Ontario, Canada. Our results suggest that plant diversity and productivity in boreal jack pine forests are significantly influenced by vegetation management treatments. Overall, release treatments did not cause a loss of diversity but benefitted stand-scale yield and individual crop tree growth, with maximum benefits occurring in more intensive release treatments. However, none of the treatments maximized all 27 indicators studied; thus, forest managers are faced with trade-offs when choosing treatments. Research on longer term effects, ideally through at least one rotation, is essential to fully understand outcomes of different vegetation management on forest diversity, stand yield, and individual crop tree responses.

Jack pine cone quality and cache sizes of red squirrels in southern New Brunswick, Canada

1997 ◽  
Vol 75 (2) ◽  
pp. 332-335 ◽  
Author(s):  
Michael A. Setterington ◽  
Daniel M. Keppie
Keyword(s):  
New Brunswick ◽  
Pinus Banksiana ◽  
Seed Mass ◽  
Dry Mass ◽  
Jack Pine ◽  
Tamiasciurus Hudsonicus ◽  
Red Squirrels ◽  
Length Width ◽  
Total Seed ◽  
Number Of Seeds

Relationships between external cone characteristics (length, width, wet and dry mass), cone quality (total seed mass as a proportion of cone mass, total number of seeds per cone, total seed mass per cone), and number of cones in caches were evaluated for caches of jack pine (Pinus banksiana) cones belonging to red squirrels (Tamiasciurus hudsonicus) in two plantations in southern New Brunswick. Cone length and mass were good predictors of the total number of seeds per cone and total seed mass per cone. Length accounted for a small proportion of the variance of total seed mass as a proportion of cone mass. There was no relationship between the number of seeds or total seed mass per cone and the number of cones per cache.

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