THE EFFECT OF SAY STINKBUG FEEDING ON WHEAT

1945 ◽  
Vol 77 (11) ◽  
pp. 200-200 ◽  
Author(s):  
L. A. Jacobson
Keyword(s):  
Western Canada ◽  
Severe Damage ◽  
The Past ◽  
Seed Crops ◽  
Chlorochroa Sayi ◽  
New Pest

Say stinkbug, Chlorochroa sayi Stal, is a comparatively new pest of wheat and other seed crops in Western Canada. In the past ten years it frequently has caused severe damage to wheat in many localized areas.

The Standing Crop of Net Plankton in Lakes

1953 ◽  
Vol 10 (5) ◽  
pp. 224-237 ◽  
Author(s):  
D. S. Rawson
Keyword(s):  
Standing Crop ◽  
Seasonal Fluctuation ◽  
Western Canada ◽  
Inverse Relation ◽  
Secondary Effects ◽  
Eutrophic Lakes ◽  
Trophic Condition ◽  
The Past

Plankton sampling has been a part of the program in a number of investigations of lakes in western Canada during the past 20 years. The techniques chosen for this work are discussed and criticized. The resulting data on average standing crop of net plankton are summarized and considered in relation to the kinds of lakes represented. The standing crop in 20 lakes shows an inverse relation to mean depth which is interpreted as indicating that, in most of these lakes, the trophic condition is greatly influenced by morphometry. Deviations from this relation appear to be explained by the secondary effects of climate and edaphic situation.The difference in quantity between the standing crops of net plankton in oligotrophic and eutrophic lakes is not large, and, of course, these lake types intergrade. This lack of sharp differentiation is further obscured by rapid and extensive seasonal fluctuation in amounts of plankton and by the difficulties inherent in present methods of sampling. These circumstances render measurements of standing crop difficult and of only moderate utility in suggesting the trophic type or the possible productivity of a lake.

INFESTIBILITY OF OILSEEDS, CLOVER, AND MILLET BY STORED-PRODUCT INSECTS

1972 ◽  
Vol 52 (4) ◽  
pp. 431-440 ◽  
Author(s):  
R. N. SINHA
Keyword(s):  
Tribolium Castaneum ◽  
Common Species ◽  
Western Canada ◽  
Cryptolestes Ferrugineus ◽  
Potential Danger ◽  
Complete Development ◽  
Stored Product Insects ◽  
Oryzaephilus Mercator ◽  
Insect Attack ◽  
New Pest

Infestation potential of 16 cultivars of flax, mustard, rape, sunflower, millet, and clover seeds to five common species of stored-product insects was determined. When multiplication was used as a criterion, whole seeds were resistant to insect attack although minor infestation occurred on certain cultivars. Although some species of insects could complete development on certain cultivars, few could reproduce well on clover and mustard cultivars. Oilseeds were more susceptible to Oryzaephilus mercator than to any other insect species. Cryptolestes ferrugineus, which thrived on the millet cultivars Crown and Siberian, neither reproduced nor completed development on any of the oilseed and forage cultivars. All cultivars of crushed Noralta, Raja, and Redwood flax were susceptible to: O. mercator, O. surinamensis, and Tribolium castaneum; Echo and Target rape only to O. mercator; Armavirec, Krasnodarets, Mennonite, and Peredovic sunflowers to all insects except C. ferrugineus; and Crown and Siberian millet to all insects. Tribolium confusum reproduced only on sunflower and millet cultivars. The potential danger of stored oilseeds in Western Canada from a new pest, O. mercator, was evaluated.

scholarly journals The Whitefly Dialeurodes citri: A New Pest on Citrus in Tunisia?

2021 ◽  
Vol 16 (1) ◽  
pp. 11-18
Author(s):  
Synda Boulahia-Kheder ◽  
Keyword(s):  
Common Species ◽  
Biological Traits ◽  
Severe Damage ◽  
Control Programs ◽  
North East ◽  
Dialeurodes Citri ◽  
Citrus Orchards ◽  
Parabemisia Myricae ◽  
Very High ◽  
New Pest

Whiteflies invaded citrus orchards in Tunisia in the 90’s. Two species: Aleurothixus floccosus and Parabemisia myricae have been recorded successively infesting citrus and causing severe damage in Cap-Bon (North-East of Tunisia). These pests were first controlled by several insecticidal applications but with a relative efficiency. Then two biological control programs have been deployed completing the action of native natural enemies especially for P. myricae. The result was a very satisfactory control of both whitefly species, to a point that they almost disappeared from orchards for about 30 years. In 2017, a third whitefly species, identified as Dialeurodes citri, was observed during a prospection in citrus orchards in Takelsa region (Cap-Bon). It was a common species in Algeria, but never caused damage in Tunisia. In 2020, D. citri was found again with very high population densities in the regions of Menzel Bou Zelfa (Cap-Bon) and Tunis. These observations confirmed its change of status and spread in Tunisia. The main morphological and biological traits to distinguish between D. citri and the other two whitefly species, already recorded in Tunisia, were described and first observations on its infestation were reported. Some recommendations to manage this new pest are given.

Non-engineered construction in developing countries

2000 ◽  
Vol 33 (3) ◽  
pp. 187-208 ◽  
Author(s):  
Anand S. ARYA
Keyword(s):  
Developing Countries ◽  
Building Construction ◽  
Disaster Mitigation ◽  
Seismic Retrofitting ◽  
Earthquake Risk ◽  
Prevention Measures ◽  
Severe Damage ◽  
Critical Elements ◽  
The Past ◽  
Earthquake Resistant

The paper first discusses some issues in regard to earthquake risk reduction of Non-engineered buildings, such as: Earthquake risk in developing countries and its management, the IDNDR - Yokoyama message emphasising on pre-disaster mitigation and preparedness, earthquake damage reduction initiatives taken such as preparation of building codes and guidelines and disaster mitigation for sustainable development. Then, the major causes of severe damage observed in non-engineered buildings in the past earthquakes are presently briefly and critical elements to be incorporated in new constructions are highlighted. Methodology for seismic retrofitting of stone houses developed, implemented and verified by the author in the field is introduced. Next, costs and benefits of earthquake prevention measures are indicated. Finally a practically feasible and economically viable scheme of earthquake resistant new building construction and seismic-retrofitting of existing unsafe buildings is outlined.

Impacts of Fish Introductions in Tropical Asia and America

1991 ◽  
Vol 48 (S1) ◽  
pp. 24-32 ◽  
Author(s):  
C. H. Fernando
Keyword(s):  
Indigenous Species ◽  
Severe Damage ◽  
Tropical Asia ◽  
The Past ◽  
Fish Introductions ◽  
Living Fossils ◽  
Lakes And Reservoirs ◽  
Reservoir Construction ◽  
Indigenous Fishes

Biotas are constantly being reshaped by invasions. Introduction is now an added route to invaders. Impacts must be viewed against the background of massive changes in type, extent and quality of freshwater habits globally and in that freshwater fishes are almost living fossils. Also, old lakes and lacustrine fishes are highly restricted geographically. Lakes are young while rivers are old. Riverine, marsh and pond fishes are not well adapted to lacustrine conditions now widespread due to reservoir construction. Some Clupeidae and Cichlidae are lacustrine-adapted and highly productive. They have therefore made major impacts on fish yields in lakes and reservoirs. In tropical Asia and America, there have been a series of overlapping waves offish introductions during the past 150 years, culminating tin the tilapias from Africa. These fishes now dominate capture and culture fisheries in many countries. Fish introductions are a fait accompli and will continue. They must be realistically assessed and carefully monitored. Contrary to some predictions, introductions have not caused severe damage to indigenous species except when piscivores were used. Yields of indigenous fishes have apparently been enhanced in some instances. Parasites pose a serious threat and only an effective quarantine will ensure their exclusion.

Late Holocene fluctuations of Stoppani Glacier, southernmost Patagonia

2020 ◽  
Vol 95 ◽  
pp. 56-64 ◽  
Author(s):  
Brian Menounos ◽  
Lyssa Maurer ◽  
John J. Clague ◽  
Gerald Osborn
Keyword(s):  
Pacific Northwest ◽  
Late Holocene ◽  
Response Times ◽  
Western Canada ◽  
Lateral Moraine ◽  
The Past ◽  
Significant Difference ◽  
Glacial Expansion ◽  
Age Range ◽  
The U.S

AbstractSome lateral moraines contain a rich record of Holocene glacial expansion. Previous workers have used such evidence to document glacial fluctuations in western Canada, Alaska, and the U.S. Pacific Northwest, but similar studies in Patagonia are uncommon. Here we report on the late Holocene behavior of Stoppani Glacier, a 75 km2 glacier sourced in the Cordillera Darwin, southernmost Patagonia. Based on radiocarbon-dated wood and organic material contained in the glacier's northeast lateral moraine, we infer that Stoppani Glacier advanced shortly before 3.8–3.6, at 3.2–2.8, 2.3–2.1, and 0.3–0.2, and possibly sometime before 1.4–1.3 and 0.8–0.7 cal ka BP. These advances culminated at 0.3–0.2 cal ka BP, when the glacier constructed a prominent end moraine, marking its greatest extent of the past 4000 years. Although the timing of several of the advances overlap with the age range of glacial expansion recognized elsewhere in Patagonia, some do not. Asynchronous behavior observed in the glacial record may arise from the type of evidence (e.g., lateral stratigraphy vs. end moraine) used to document glacial fluctuations or variations in climate or glacial response times. A significant difference between the Stoppani record and some other Patagonian records is that the former indicates general expansion of ice over the last 4000 years, whereas the latter indicate a net decrease in extent over that period.

LOCAL WEED PROBLEMS

1955 ◽  
pp. 62-69
Author(s):  
L.J. Matthews
Keyword(s):  
Natural Hazard ◽  
Red Clover ◽  
The Past ◽  
Small Seed ◽  
Seed Crops

In the past the farmer in Hawkes Bay regarded weeds as a natural hazard. As such he accepted them. With the development of selective weedkillers.there is at least a straw for him to clutch at. In a 1954 survey the most important problems listed for Hawkes Bay were the pasture weeds, barley grass, thistles, blackberry and gorse, and the crop weeds in lucerne, red clover, brassicas, small seed crops and peas. The list also included over 20 other prevalent weeds, docks, weeds in drains, etc. In this paper I intend discussing the more important problems for which chemical weedkillers are of value.

scholarly journals “Jean Barman — Vernacular Historian”

2017 ◽  
Vol 27 (2) ◽  
pp. 136-146
Author(s):  
Heather Devine
Keyword(s):  
Pacific Northwest ◽  
Mixed Race ◽  
Indigenous Studies ◽  
Western Canada ◽  
French Canadians ◽  
Historical Sources ◽  
The Past ◽  
The Pacific ◽  
Personal Experiences ◽  
Vernacular History

Over the past year, several excellent new publications focused on the histories of mixed-race French-Canadian communities in western Canada and the Pacific Northwest. Of these books, Jean Barman’s French Canadians, Furs and Indigenous Women in the Making of the Pacific Northwest merits special attention, because the author has successfully sought out, and integrated, vernacular voices as historical sources. And for this reason, Jean Barman is sometimes referred to as a “vernacular,” or grassroots historian. What is vernacular history? Is this genre a product of methodology or of one’s worldview? And can a vernacular approach to history help scholars navigate the increasingly politicised environment of indigenous studies? The author reflects on these questions, by sharing some of her personal experiences with Jean Barman that illustrate the complexity of the issues surrounding indigenous historical practice today.

Le Passé a-t-il de l'avenir devant lui? Bilan du théâtre francophone de l'Ouest canadien

1996 ◽  
Vol 21 (3) ◽  
pp. 208-218
Author(s):  
Ingrid Joubert
Keyword(s):  
Nineteenth Century ◽  
Human Rights ◽  
Minority Groups ◽  
Western Canada ◽  
The Past ◽  
French Speaking ◽  
History Of ◽  
Indian Relations ◽  
Anglo Indian

For the French speaking minorities of Manitoba, the struggle against oppression has often meshed with battles for justice and human rights waged by other Canadian minority groups. Over the past two decades, plays by English and French speaking playwrights have echoed theatrical themes of the nineteenth century by centring on the plight of the Métisse. Being of Amer-Indian and Franco-Canadian descent, the history of the Métisse offers a fascinating perspective on Anglo-French and Anglo-Indian relations. In many of the plays, much attention is paid to the legendary story of Louis Riel, a Métisse chief who led the fight against British expansion into Western Canada and who was executed by the Crown for the murder of Thomas Scott, a British officer. With Riel as an emblem, anglophone and francophone playwrights have forged new outlooks on the historical struggle for control of Western Canada. Furthermore, while investigating the past playwrights have uncovered ways in which conflicting interpretations of history throw light upon present-day Canadian cultural complexities.

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