The biology of Canadian weeds.: 97. Barbarea vulgaris R.Br.

1991 ◽  
Vol 71 (1) ◽  
pp. 149-166 ◽  
Author(s):  
Marilyn A. MacDonald ◽  
Paul B. Cavers
Keyword(s):  
British Columbia ◽  
Key Words ◽  
Seed Production ◽  
Seed Dormancy ◽  
Rapid Growth ◽  
Barbarea Vulgaris ◽  
Weed Biology ◽  
Southern Ontario ◽  
Grain Crops ◽  
Disturbed Areas

Barbarea vulgaris R.Br. is an introduced weed of recently disturbed areas, small-seeded grain crops, roadsides and pastures. It is abundant in southern Ontario, Quebec and the northeastern U.S.A.; frequent in the Maritimes, British Columbia and the northwest coastal U.S.A.; and rare south of 33°N, north of 50°N and across the prairies. The weediness of this species largely results from its prolific seed production, enforced and induced seed dormancy, and its rapid growth under favourable conditions. Key words: Barbarea vulgaris, yellow rocket, weed biology

The Biology of Canadian Weeds. 111. Anthriscus sylvestris (L.) Hoffm

1999 ◽  
Vol 79 (4) ◽  
pp. 671-682 ◽  
Author(s):  
S. J. Darbyshire ◽  
R. Hoeg ◽  
J. Haverkort
Keyword(s):  
British Columbia ◽  
Key Words ◽  
Vegetative Reproduction ◽  
Old Fields ◽  
Eastern Canada ◽  
Weed Biology ◽  
Perennial Crops ◽  
Anthriscus Sylvestris ◽  
Disturbed Areas

Wild chervil, Anthriscus sylvestris (L.) Hoffm. (Apiaceae), is a weed of perennial crops, old fields, disturbed areas and roadsides. Introduced from Eurasia, it is widely naturalized in eastern Canada from Newfoundland to Ontario and at two sites in British Columbia. It is a monocarpic short-lived perennial, reproducing by seed and budding from the root crown. Dense populations achieved through vegetative reproduction can exclude most other vegetation. The rust, Puccinia pimpinellae subsp. pimpinellae, was detected on a population of wild chervil from Quebec. Key words: Wild chervil, Anthriscus sylvestris, weed biology

Biology and management of Echinochloa colona and E. crus-galli in the northern grain regions of Australia

2019 ◽  
Vol 70 (11) ◽  
pp. 917 ◽  
Author(s):  
Asad Shabbir ◽  
Bhagirath S. Chauhan ◽  
Michael J. Walsh
Keyword(s):  
Seed Production ◽  
Seed Dormancy ◽  
Rapid Growth ◽  
Cropping Systems ◽  
Control Strategies ◽  
Yield Losses ◽  
Annual Grass ◽  
Fallow Management ◽  
Current Information ◽  
Wide Range

Echinochloa colona and E. crus-galli are two important annual grass weeds distributed throughout the summer cropping regions of Australia. Both species are highly problematic weeds, responsible for yield losses of up to 50% in summer grain crops. The success of Echinochloa species as weeds is attributed to their rapid growth, prolific seed production, seed dormancy and adaptability to a wide range of environments. Importantly, E. colona has evolved resistance to glyphosate in Australia, with resistant populations now widespread across the summer cropping regions. Fallow management of E. colona with glyphosate alone is risky in terms of increasing the chance of resistance and highly unsustainable; other control strategies (residual herbicides, strategic tillage, etc.) should be considered to complement herbicides. This review provides a summary of current information on the biology, ecology and management of Echinochloa species. The knowledge gaps and research opportunities identified will have pragmatic implications for the management of these species in Australian grain cropping systems.

AEC Glacier alpine bluegrass

2002 ◽  
Vol 82 (1) ◽  
pp. 95-98 ◽  
Author(s):  
B. A. Darroch ◽  
S. N. Acharya ◽  
J. Woosaree
Keyword(s):  
Key Words ◽  
Seed Production ◽  
Rapid Growth ◽  
Cultivar Description ◽  
High Elevations ◽  
Key Words Alpine

AEC Glacier alpine bluegrass, Poa alpina L., is a reclamation cultivar developed for use in reclaiming and revegetating disturbed sites at high elevations. It is the second alpine bluegrass cultivar released by the Alberta Environmental Centre, Vegreville, AB. This cultivar is expected to complement a prior release, AEC Blueridge alpine bluegrass. AEC Glacier is adapted to high elevations where it is capable of rapid growth and seed production. Key words: Alpine bluegrass, Poa alpina, cultivar description, reclamation

Cotton grass (Eriophorum vaginatum) germination requirements and colonizing potential in the Arctic

1973 ◽  
Vol 51 (12) ◽  
pp. 2509-2513 ◽  
Author(s):  
Ross W. Wein ◽  
D. A. MacLean
Keyword(s):  
Seed Production ◽  
Seed Dormancy ◽  
Light Treatment ◽  
The Arctic ◽  
Native Grasses ◽  
Eriophorum Vaginatum ◽  
Grass Seed ◽  
Disturbed Areas ◽  
Moisture Conditions ◽  
Germination Requirements

Germination requirements of cotton grass (Eriophorum vaginatum L.) were investigated to determine its potential for reseeding disturbed areas of the arctic tundra. Maximum seed production was 15.7 kg/ha, although production and viability varied widely. There was no seed dormancy and temperatures of 25–30 °C produced maximum germination rates. A light treatment enhanced germination but was not required. Cotton grass seed germinated under less favorable moisture conditions than several other native grasses that strongly invade disturbed arctic sites. Loss of viability during storage under room conditions was high for the first 10 months, yet 27.6–52.5% of the seed remained viable at 19 months. The role that this species could play in revegetation is discussed.

The effects of smut (Ustilago destruens) on seed production, dormancy, and viability in fall panicum (Panicum dichotomiflorum)

1995 ◽  
Vol 73 (10) ◽  
pp. 1628-1634 ◽  
Author(s):  
Thevaki Govinthasamy ◽  
Paul B. Cavers
Keyword(s):  
Key Words ◽  
Seed Production ◽  
Seed Dormancy ◽  
Seed Viability ◽  
Large Seed ◽  
Viable Seeds ◽  
Panicum Dichotomiflorum

Fall panicum (Panicum dichotomiflorum var. geniculatum), an abundant annual weed in southwestern Ontario, suffers large seed losses from the smut Ustilago destruens. From 19 to 83% of plants were infected in three sites surveyed. Some infected plants were completely sterile, but others produced small numbers of viable seeds. Most of these seeds did not give rise to smut-infected plants if they were not exposed to smut teliospores in the soil over winter. Compared with seeds from uninfected plants, those from infected plants had lower percent viability and weaker dormancy. When seeds from either infected or uninfected plants were mixed with smut teliospores over winter, 39% of the resulting plants were smut infected, compared with less than 1% of plants from seeds overwintered without smut teliospores. Seeds mixed with smut teliospores over winter did not lose viability, but some of them were slower to germinate the following spring. Key words: smut, fall panicum, seed viability, seed dormancy, germination, Ustilago destruens, Panicum dichotomiflorum.

THE BIOLOGY OF CANADIAN WEEDS.: 87. Cynoglossum officinale L.

1988 ◽  
Vol 68 (3) ◽  
pp. 763-774 ◽  
Author(s):  
MAHESH K. UPADHYAYA ◽  
HEIDY R. TILSNER ◽  
MICHAEL D. PITT
Keyword(s):  
North America ◽  
Environmental Stress ◽  
Seed Production ◽  
Seed Dormancy ◽  
Cynoglossum Officinale ◽  
Weed Biology ◽  
Perennial Weed ◽  
Animal Hair ◽  
And Control

Cynoglossum officinale L. is a biennial or short-lived perennial weed which reproduces by seed. It has been introduced to North America from Eurasia. Although usually not a weed of cultivated fields, C. officinale may become a serious rangeland weed. High seed production, seed dormancy, dissemination by attaching seeds to animal hair, wool and fur, plus the ability to withstand environmental stress are important in the success of C. officinale as a weed. Because C. officinale foliage is toxic to both cattle and horses, it is a particular problem in areas where grazing occurs. This paper reviews the biology and control of C. officinale.Key words: Weed biology, Cynoglossum officinale L., hound’s tongue

THE BIOLOGY OF CANADIAN WEEDS.: 68. Crataegus crus-galli L. sensu lato

1985 ◽  
Vol 65 (3) ◽  
pp. 641-654 ◽  
Author(s):  
T. A. DICKINSON
Keyword(s):  
Key Words ◽  
Agricultural Land ◽  
Fleshy Fruit ◽  
Great Abundance ◽  
Weed Biology ◽  
Southern Ontario ◽  
Reproductive Characteristics ◽  
Large Numbers

Crataegus crus-galli L. sensu lato (cockspur hawthorn) is one of the most readily identified Canadian hawthorns. It occurs frequently, and often in great abundance, on abandoned or poorly managed agricultural land in southern Ontario. These shrubs or small trees are difficult to remove and because of their thorns highly resistant to grazing. The weediness of cockspur hawthorn appears to be a function principally of reproductive characteristics (apomixis and self-fertility in abundant, unspecialized flowers each of which may develop into a fleshy fruit) that result in the production and dispersal of large numbers of seed annually (or biennially).Key words: Weed biology, cockspur hawthorn, Crataegus crus-galli, distribution

Production of uredinia and telia by stalactiform blister rust in British Columbia

1993 ◽  
Vol 71 (3) ◽  
pp. 519-521 ◽  
Author(s):  
B. J. van der Kamp
Keyword(s):  
British Columbia ◽  
Life Cycle ◽  
Key Words ◽  
Alternate Host ◽  
Alternate Hosts ◽  
Blister Rust ◽  
Dry Areas ◽  
Do So

Records of uredinia and telia production on the alternate hosts of Cronartium coleosporioides in British Columbia and inoculation of Castilleja miniata with aeciospores collected from various locations showed that rust isolates from dry areas of the interior of British Columbia do not produce uredinia and may have lost the ability to do so. Collections from somewhat wetter areas produced uredinia or mixtures of uredinia and telia immediately following aeciospore inoculations, and field collections from such areas in June commonly had mixtures of uredinia and telia. Loss of the uredinial stage may be a response to climates that are often unsuitable for the spread or survival of the rust on the alternate host. Key words: stalactiform rust, uredinia, telia, rust life cycle.

scholarly journals Fungal colonizers and seed loss in lodgepole pine orchards of British Columbia

Botany ◽  
2019 ◽  
Vol 97 (1) ◽  
pp. 23-33
Author(s):  
Paul Y. de la Bastide ◽  
Jonathon LeBlanc ◽  
Lisheng Kong ◽  
Terrie Finston ◽  
Emily M. May ◽  
...  
Keyword(s):  
British Columbia ◽  
Seed Production ◽  
Pinus Contorta ◽  
Lodgepole Pine ◽  
Seed Viability ◽  
Molecular Approaches ◽  
Seed Loss ◽  
Natural Range ◽  
Fungal Microbiome ◽  
Host Tissues

Lodgepole pine (Pinus contorta var. latifolia Engelm. ex S. Watson) is an important lumber species in Canada, and seed orchards are expected to meet the increased demand for seed. However, seed production has been consistently low in the Okanagan region orchards of British Columbia, Canada. To determine whether the fungal microbiome contributes to seed loss, histological and molecular approaches were used. Seed production was studied at seven Okanagan orchards, all outside the natural range of lodgepole pine, and at one near Prince George, within its natural range. Seed losses were highest in the Okanagan, compared with Prince George. The role of fungal colonizers in consuming seed during the last stages of maturation is described. Fungal hyphae were frequently observed at all locations in developing seed, particularly once storage substances accumulated. Fungi identified from host tissues using molecular and morphological techniques included Alternaria, Cladosporium, Fusarium, Penicillium, and Sydowia. The opportunistic foliar pathogen Sydowia polyspora, which is known to have a variable biotrophic status, was detected at most orchards within different host tissues (seeds, needles, and conelets), in association with pollen, and in the air column. Reduced seed viability observed in Okanagan orchards is most likely due to a combination of factors, including composition of the fungal microbiome.

Insects Affecting Seed Production in Red Pine: IV. Recognition and Extent of Damage to Cones

1957 ◽  
Vol 89 (6) ◽  
pp. 264-271 ◽  
Author(s):  
L. A. Lyons
Keyword(s):  
Seed Production ◽  
Production Capacity ◽  
Red Pine ◽  
Natural Control ◽  
Present Contribution ◽  
Southern Ontario ◽  
Pine Cone ◽  
Poor Seed ◽  
Extent Of Damage ◽  
Cone Damage

The broad study of factors responsible for poor seed production by red pines (Pinus resinosae Ait.) in central and southern Ontario has been concerned with the seed production capacity and efficiency of sound cones (1) and the description, life history, behaviour, and natural control of cone-inhabiting insects (2, 3, 4). The present contribution, which concludes the four-part series on red pine cone insects, deals with the time and duration of cone attack by the various insect species and the variability in the intensity of cone damage from year to year and from one locality to another. As an aid to the field diagnosis of the cause of cone damage, keys based on the appearance of mature larvae and injured cones are included.

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