Effect of Temperature on Fecundity and Survival of Chrysolina quadrigemina (Suffr.) and C. hyperici (Forst.) (Coleoptera: Chrysomelidae)

1962 ◽  
Vol 94 (7) ◽  
pp. 774-780 ◽  
Author(s):  
P. Harris
Keyword(s):  
Biological Control ◽  
British Columbia ◽  
Hypericum Perforatum ◽  
The Other ◽  
Effect Of Temperature ◽  
Low Density

Four colonies of Chrysolina quadrigemina (Suffr.) and two of C. hyperici (Forst.) were released in 1951 and 1952 in the souvhern interior of British Columbia (Fig. 1) in the hope of duplicating the successful biological control of Hypericum perforatum L. in California. In 1956, Smith (1958) showed that though the colonies were still present, the weed had increased in all areas. By 1960, however, C. hyperici had greatly reduced the abundance of H. perforatum at Fruitvale (Fig. 2) while at Edgewood the beetle had disappeared. A colony of C. padrigmina at Edgewood had also disappeared and the three other C. quadrigemina colonies persisted at a low density without controlling the weed. For example, at Christina Lake (Fig. 3) a few beetles were found every year since release, though they had not always appeared in the sample plots. The annual fluctuations of the weed as indicated in the figure were probably of climatic origin as they were similar to those for the other areas. The most promising of the C. quadrigemina colonies was at Fife where, though there were few beetles in the release meadow itself, they were common on the slope below.

AN ECONOMIC EVALUATION OF CONTROL METHODS FOR DIFFUSE AND SPOTTED KNAPWEED IN WESTERN CANADA

1979 ◽  
Vol 59 (2) ◽  
pp. 375-382 ◽  
Author(s):  
P. HARRIS ◽  
R. CRANSTON
Keyword(s):  
Biological Control ◽  
British Columbia ◽  
Economic Evaluation ◽  
Cost Effective ◽  
The Other ◽  
Western Canada ◽  
Spotted Knapweed ◽  
Control Methods ◽  
Effective Solution ◽  
Introduced Weeds

Diffuse and spotted knapweed are introduced weeds that threaten to spread throughout the uncultivated drylands of Western Canada. By 1972 approximately 30 000 ha, mostly in British Columbia, were infested, with forage reductions of up to 88%. Presently the infestation may be increasing by 10% a year and it is estimated that 8.4–10.7 million ha are susceptible to invasion by one or the other species in Western Canada. This would be disastrous to both ranching and wildlife in the region. The economics of various options for control are discussed. Biological control, which is likely to require the introduction of six agents and cost a total of $1.8 million, is the most cost-effective solution. However, until it can be fully implemented (10–20 yr) new infestations can be spot-treated with picloram. It is also economic to convert dense stands to tame pasture after killing the knapweed with picloram at 0.5 kg/ha although the knapweed is likely to begin reinvasion after 4 yr.

FIRST REPORT OF THE DISPERSAL INTO MONTANA OF UROPHORA QUADRIFASCIATA (DIPTERA: TEPHRITIDAE), A FLY RELEASED IN CANADA FOR BIOLOGICAL CONTROL OF SPOTTED AND DIFFUSE KNAPWEED

1985 ◽  
Vol 117 (8) ◽  
pp. 1061-1062 ◽  
Author(s):  
Jim M. Story
Keyword(s):  
Biological Control ◽  
British Columbia ◽  
The United States ◽  
Flower Head ◽  
The Other ◽  
Centaurea Maculosa ◽  
Spotted Knapweed ◽  
European Origin ◽  
Mature Flower ◽  
Diffuse Knapweed

Two tephritid flies of European origin have been introduced into North America for biological control of spotted knapweed, Centaurea maculosa Lam., and diffuse knapweed, C. diffusa Lam. One, Urophora affinis Frauenfeld, was released in British Columbia in 1970 and in 5 states, including Montana, in 1973 (Hanis 1980a; Maddox 1979; Story and Anderson 1978). The other, Urophora quadrifasciata (Meigen), was introduced at Ned's Creek, British Columbia but was not released in the United States. The larvae of both flies induce galls (1 larva/gall) in immature knapweed flower heads and thus reduce seed production. Galls of Urophora affinis occur in the flower-head receptacle whereas galls of U. quadrifasciata are in the ovary wall. In contrast with U. affinis, which has only a partial second generation, U. quadrifasciata normally has 2 complete generations per year, induces thinner galls, and attacks more-mature flower heads than does U. affinis (Harris 1980a).

A Note on Colour Preferences of Some Homoptera and Thysanoptera in British Columbia

1962 ◽  
Vol 94 (1) ◽  
pp. 107-107 ◽  
Author(s):  
W. H. A. Wilde
Keyword(s):  
Biological Control ◽  
British Columbia ◽  
Sweet Cherry ◽  
Control Unit ◽  
The Other ◽  
Department Of Agriculture ◽  
Canada Department ◽  
Pear Trees ◽  
Colour Preferences ◽  
Cherry Trees

In pear and sweet cherry orchards near Creston, in the Kootenay Valley of British Columbia, populations of psyllids, aphids, thrips and leafhoppers were sampled by yellow, and white, sticky board traps hung in the trees. The psyllids were adult Psylla pyricola Först., caught in pear trees; the other insects were caught in cherry trees. The latter insects were: alate Myzus cerasi (F.), adults and nymphs of Taeniothrips sp., and adult leafhoppers of the following species: Edwardsiana rosae (L.), Macrosteles fascifrons (Stål), Psammotettix lividellus (Zett.), Dikraneura absenta DeL. and C., Scaphytopius acutus (Say), Osbornellus borealis DeL. and Mohr., Neokolla hieroglyphics (Say), and Erythroneura spp. Identifications were made by the Systematics and Biological Control Unit of the Canada Department of Agriculture, Ottawa.

THE STATUS OF BIOLOGICAL CONTROL OF THE WEED HYPERICUM PERFORATUM IN BRITISH COLUMBIA

1969 ◽  
Vol 101 (1) ◽  
pp. 1-15 ◽  
Author(s):  
P. Harris ◽  
D. Peschken ◽  
J. Milroy
Keyword(s):  
Biological Control ◽  
British Columbia ◽  
Hypericum Perforatum ◽  
The Status

AbstractBiological control attempts against the weed Hypericum perforatum L. in the interior of British Columbia are summarized. Three of the insects introduced, Zeuxidiplosis giardi Kieff., Agrilus hyperici (Cr.), and Chrysolina varians (Schall.), did not survive, and reasons for their failure are discussed. Two beetles, C. hyperici (Forst.) and C. quadrigemina (Suff.), are established and their population build-up in several areas is followed over a period of 15 years. The beetles reach their optimum effectiveness in different moisture zones but neither species is effective at the arid end of the H. perforatum range. A moth, Anaitis plagiata L., was released in this zone in 1967.

Gemmae in Tetralophozia setiformis (Anastrophyllaceae, Marchantiophyta) and their second record in Eurasia

2017 ◽  
Vol 51 ◽  
pp. 242-250
Author(s):  
M. V. Dulin
Keyword(s):  
British Columbia ◽  
Asexual Reproduction ◽  
Leaf Shape ◽  
Leaf Size ◽  
Komi Republic ◽  
The Other ◽  
Widespread Species ◽  
Northern Urals ◽  
Sexual And Asexual Reproduction ◽  
Murmansk Region

Tetralophozia setiformis is a widespread species occurring usually without organs of sexual and asexual reproduction. Gemmae of Tetralophozia setiformis were observed for the second time in Russia and Eurasia in the Northern Urals, Komi Republic. They form compact masses over upper leaves. The compact masses consist largely (70 %) of immature gemmae. Description of gemmae and gemmiparous shoots from the Northern Urals and their comparison with those from the other known localities, namely British Columbia (Canada) and the Murmansk Region (European Russia) were carried out. The gemmiparous plants of T. setiformis from the Northern Urals have approximately the same width as plants without gemmae but they are shorter. The leaves of gemmiparous plants from the Northern Urals are similar to leaves of gemmiparous plants from British Columbia. The leaf shape in upper part of the gemmiparous shoots varies from the typical to ± modified from gemmae production. These leaf shape transitions include reduction of leaf size and lobe number from 4 to 2–3, suppression of development and disappearance of characteristic teeth at the base of sinus. Gemmae size (17 × 22 μm) of plants from the Northern Urals is within variability recorded for plants from the Murmansk Region and British Columbia.

scholarly journals The Respiration of some Planktonic copepods II. The Effect Of Temperature

1953 ◽  
Vol 31 (3) ◽  
pp. 447-460 ◽  
Author(s):  
D. T. Gauld ◽  
J. E. G. Raymont
Keyword(s):  
Respiratory Rate ◽  
The Body ◽  
The Other ◽  
Effect Of Temperature ◽  
Acartia Clausi ◽  
Temora Longicornis ◽  
Different Temperatures ◽  
Planktonic Copepods ◽  
The Difference ◽  
The Relationship

The respiratory rates of three species of planktonic copepods, Acartia clausi, Centropages hamatus and Temora longicornis, were measured at four different temperatures.The relationship between respiratory rate and temperature was found to be similar to that previously found for Calanus, although the slope of the curves differed in the different species.The observations on Centropages at 13 and 170 C. can be divided into two groups and it is suggested that the differences are due to the use of copepods from two different generations.The relationship between the respiratory rates and lengths of Acartia and Centropages agreed very well with that previously found for other species. That for Temora was rather different: the difference is probably due to the distinct difference in the shape of the body of Temora from those of the other species.The application of these measurements to estimates of the food requirements of the copepods is discussed.

scholarly journals The influence of two wildfires and biological control agents on the population dynamics of Melaleuca quinquenervia in a seasonally inundated wetland

2021 ◽  
Vol 14 (1) ◽  
pp. 3-8
Author(s):  
Philip W. Tipping ◽  
Melissa R. Martin ◽  
Jeremiah R. Foley ◽  
Ryan M. Pierce ◽  
Lyn A. Gettys
Keyword(s):  
Biological Control ◽  
Population Dynamics ◽  
Seedling Recruitment ◽  
Additional Treatment ◽  
Seed Rain ◽  
The Other ◽  
Melaleuca Quinquenervia ◽  
Biological Control Agents ◽  
Seedling Mortality ◽  
Sapling Growth

AbstractThe potential of Melaleuca quinquenervia (Cav.) S.T. Blake to reinvade cleared areas was evaluated over a 13-yr period that included two wildfires and the introduction of biological control agents. The first wildfire occurred in 1998 and was followed by a mean of 591.5 recruited seedlings m−2. Recruits from that fire were cleared 7 yr later in July 2005 for a second experiment to evaluate seedling recruitment into cleared areas. Seed rain, seedling recruitment and mortality, and sapling growth rates were measured in four plots located around individual large reproductive trees. A second natural wildfire in 2007 burned through those plots, leading to increases in seed rain followed by a pulse in recruitment of 21.04 seedlings m−2, 96.5% fewer than after the 1998 fire. Recruits in half of the plots around each tree were then treated with regular applications of an insecticide to restrict herbivory by biological control agents, while herbivory was not restricted in the other half. There was no difference in seedling mortality between treatments 1,083 d post-fire (2007) with 96.6% seedling mortality in the unrestricted herbivory treatment and 89.4% mortality in the restricted herbivory treatment. Recruits subjected to the restricted herbivory treatment grew taller than those in the unrestricted herbivory treatment, 101.3 cm versus 37.4 cm. Many of the recruits were attacked by the biological control agents, which slowed their growth. Although solitary M. quinquenervia trees retain some capacity to reinvade areas under specific circumstances, there was a downward trend in their overall invasiveness at this site, with progressively smaller recruitment cohorts due to biological control agents. Land managers should prioritize removing large reproductive trees over treating recently recruited populations, which can be left for many years for the biological control agents to suppress before any additional treatment would be needed.

Applied Anthropology in 1860

1942 ◽  
Vol 1 (3) ◽  
pp. 19-32
Author(s):  
H. Barnett
Keyword(s):  
British Columbia ◽  
Church And State ◽  
Applied Anthropology ◽  
The Other ◽  
Public And Private ◽  
Other Hand ◽  
The Subject ◽  
Long Life

Much has been written of William Duncan, "the Apostle of Alaska", who came to the coast of northern British Columbia in 1857 as a missionary to the Tsimshian Indians. Although he deplored it, in the course of his sixty years' residence in this area controversy raged around him as a result of his clashes with church and state, and his work has been the subject of numerous investigations, both public and private. His enemies have called him a tyrant and a ruthless exploiter of the Indians under his control; and there are men still living who find a disproportionate amount of evil in the good that he did, especially during the declining years of his long life. On the other hand, he has had ardent and articulate supporters who have written numerous articles and no less than three books in praise of his self-sacrificing ideals and the soundness of his program for civilizing the Indian.

scholarly journals Effect of Temperature on the Corrosion Inhibition of Trans-4-Hydroxy-4′-Stilbazole on Mild Steel in HCl Solution

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Ayssar Nahlé ◽  
Ideisan I. Abu-Abdoun ◽  
Ibrahim Abdel-Rahman
Keyword(s):  
Weight Loss ◽  
Double Bond ◽  
Adsorption Isotherm ◽  
Mild Steel ◽  
Corrosion Inhibitor ◽  
Thermodynamic Parameters ◽  
The Other ◽  
Effect Of Temperature ◽  
Temkin Adsorption Isotherm ◽  
Hcl Solution

The inhibition and the effect of temperature and concentration of trans-4-hydroxy-4′-stilbazole on the corrosion of mild steel in 1 M HCl solution was investigated by weight loss experiments at temperatures ranging from 303 to 343 K. The studied inhibitor concentrations were between  M and  M. The percentage inhibition increased with the increase of the concentration of the inhibitor. The percentage inhibition reached about 94% at the concentration of  M and 303 K. On the other hand, the percentage inhibition decreased with the increase of temperature. Using the Temkin adsorption isotherm, the thermodynamic parameters for the adsorption of this inhibitor on the metal surface were calculated. Trans-4-hydroxy-4′-stilbazole was found to be a potential corrosion inhibitor since it contained not only nitrogen and oxygen, but also phenyl and pyridine rings that are joined together with a double bond (–C=C–) in conjugation with these rings.

scholarly journals Sex Differentiation in Amphibians: Effect of Temperature and Its Influence on Sex Reversal

2021 ◽  
pp. 1-11
Author(s):  
Adrián Ruiz-García ◽  
Álvaro S. Roco ◽  
Mónica Bullejos
Keyword(s):  
Sexual Differentiation ◽  
Sex Differentiation ◽  
Environmental Contaminants ◽  
Natural Populations ◽  
Sex Reversal ◽  
The Other ◽  
Effect Of Temperature ◽  
Amphibian Species ◽  
Expected Increase

The role of environmental factors in sexual differentiation in amphibians is not new. The effect of hormones or hormone-like compounds is widely demonstrated. However, the effect of temperature has traditionally been regarded as something anecdotal that occurs in extreme situations and not as a factor to be considered. The data currently available reveal a different situation. Sexual differentiation in some amphibian species can be altered even by small changes in temperature. On the other hand, although not proven, it is possible that temperature is related to the appearance of sex-reversed individuals in natural populations under conditions unrelated to environmental contaminants. According to this, temperature, through sex reversal (phenotypic sex opposed to genetic sex), could play an important role in the turnover of sex-determining genes and in the maintenance of homomorphic sex chromosomes in this group. Accordingly, and given the expected increase in global temperatures, growth and sexual differentiation in amphibians could easily be affected, altering the sex ratio in natural populations and posing major conservation challenges for a group in worldwide decline. It is therefore particularly urgent to understand the mechanism by which temperature affects sexual differentiation in amphibians.

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