THE BIOLOGY OF CANADIAN WEEDS.: 89. Carduus nutans L. and Carduus acanthoides L.

Carduus nutans L. and C. acanthoides L. are introduced weeds, primarily of roadsides, fields and pasturelands. Both species occur in eastern and western Canada with C. nutans more common than C. acanthoides in western Canada. High seed production and germination rate on open soil contribute to the success of the species as weeds, as do the spiny leaves and stems which deter grazing by animals. Mowing or the application of hormone-like herbicides are both effective means of control. Biological control methods have also been used for both species, but have been most successful in the control of C. nutans.Key words: Musk thistle, nodding thistle, plumeless thistle, Carduus spp.

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

Canadian Journal of Plant Science ◽

10.4141/cjps79-060 ◽

1979 ◽

Vol 59 (2) ◽

pp. 375-382 ◽

Cited By ~ 48

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.

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Infection Potential of Pleospora allii and Evaluation of Methods for Reduction of the Overwintering Inoculum of Brown Spot of Pear

Plant Disease ◽

10.1094/pd-90-1511 ◽

2006 ◽

Vol 90 (12) ◽

pp. 1511-1516 ◽

Cited By ~ 15

Author(s):

Isidre Llorente ◽

Albert Vilardell ◽

Emilio Montesinos

Keyword(s):

Biological Control ◽

Brown Spot ◽

Control Methods ◽

Optimum Temperature ◽

Chemical Methods ◽

Stemphylium Vesicarium ◽

Mechanical Methods ◽

Pleospora Allii ◽

Evaluation Of Methods

The capacity for germination and pathogenicity to pear leaves of ascospores of Pleospora allii, the teleomorph of Stemphylium vesicarium, causal agent of brown spot of pear, were studied in vitro. Most ascospores germinated within 1 h at temperatures between 15 and 20°C, and the optimum temperature for germination was 18.9°C. Infections developed on wounded and non-wounded detached pear leaves, but were more frequent on wounded leaves. The minimum infective dose was one ascospore per wound. Biological, chemical, and mechanical methods for decreasing overwintering inoculum of P. allii were evaluated. Ascospores were discharged from March to May, depending on the orchard and year. Leaf shredding or removal were the most effective methods of reducing overwintering inoculum. Biological control methods based on application of Thichodermasp. formulations were partially effective. Chemical methods based on copper and urea treatments were ineffective.

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FURTHER STUDIES ON NATURAL SELECTION AMONG HYBRIDS OF CARDUUS ACANTHOIDES AND CARDUUS NUTANS

Canadian Journal of Botany ◽

10.1139/b64-160 ◽

1964 ◽

Vol 42 (12) ◽

pp. 1605-1613 ◽

Cited By ~ 12

Author(s):

R. J. Moore ◽

G. A. Mulligan

Keyword(s):

Natural Selection ◽

Chromosome Number ◽

Parental Species ◽

Experimental Studies ◽

Great Decrease ◽

Carduus Acanthoides ◽

Carduus Nutans ◽

Experimental Plots ◽

Better Than ◽

Made In

A third 5-year survey made in 1962 of Carduus acanthoides, C. nutans, and their hybrids in Grey Co., Ontario, revealed that a great decrease in these populations had occurred. C. acanthoides and hybrids similar to this species had survived better than C. nutans but very little spread of either species seemed to have occurred in 1957–1962. In experimental plots the hybrid has been made and backcrossed to the parental species. The species differ in chromosome number (C. acanthoides, 2n = 22; C. nutans, 2n = 16) and hybrids have intermediate numbers. Evidence was found from field and experimental studies that the progeny of the F1 hybrid included a greater proportion of seedlings with the higher chromosome numbers than with the lower and intermediate numbers. It is suggested that this selection may operate through the rejection of the longer chromosomes received from C. nutans, which, in certain zygotic combinations may constitute an excess of chromatin lethal to the zygote.

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Biological Control Against the Cowpea Weevil (Callosobruchus Chinensis L., Coleoptera: Bruchidae) Using Essential Oils of Some Medicinal Plants

Journal of Plant Protection Research ◽

10.2478/jppr-2014-0032 ◽

2014 ◽

Vol 54 (3) ◽

pp. 211-217 ◽

Cited By ~ 4

Author(s):

Righi Assia Fatiha ◽

Righi Kada ◽

Anouar Khelil ◽

Juli Pujade-Villar

Keyword(s):

Biological Control ◽

Medicinal Plants ◽

Essential Oils ◽

Germination Rate ◽

Callosobruchus Chinensis ◽

Cowpea Weevil ◽

Chick Pea ◽

Males And Females ◽

Germinating Seeds ◽

Different Doses

Abstract Chickpea (Cicer arietinum L.) is a valuable foodstuff but unfortunately this legume is prone to insect attacks from the chick pea weevil (Callosobruchus chinensis L.). This serious pest damages the chickpea and causes decreases in the yield and in the nutritional quality. Biological control is being used to deal with this problem. We tried different doses of the essential oils of three new medicinal plants, namely Salvia verbenaca L., Scilla maritima L., and Artemisia herba-alba Asso to limit the damage of the chick pea weevil pest, and to protect consumer’s health. To determine the effect and efficiency of the oil, the tests were conducted using the different biological parameters of fertility, longevity, and fecundity, under controlled temperature and relative humidity (28°C and 75%). The effectiveness of organic oils was demonstrated. We tested these oils on the germination of seeds. The obtained results showed that the tested plant oils have a real organic insecticide effect. The essential oil of Artemisia proved most effective as a biocide; achieving a mortality rate of 100%. A significant reduction in longevity was observed under the effect of 30 μl of S. maritima (1.3 days) and S. verbenaca (2.8, 4.6 days), respectively, for males and females compared to 8 and 15 days for the control. For fecundity, an inhibition of oviposition was obtained using 30 μl of Salvia and Scilla essential oils. The test on the seed germination using different essential oils, showed no damage to the germinating seeds. The germination rate was 99%. These findings suggest that the tested plants can be used as a bioinsecticide for control of the C. chinensis pest of stored products.

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Opportunities for developing value-added brassica seed

NZGA: Research and Practice Series ◽

10.33584/rps.14.2008.3174 ◽

2010 ◽

Vol 14 ◽

pp. 139-146

Author(s):

Van De Jong ◽

B.E. Braithwaite ◽

T.L. Roush ◽

A. Stewart ◽

J.G. Hampton

Keyword(s):

Biological Control ◽

New Zealand ◽

Xanthomonas Campestris ◽

Cultural Practices ◽

Effective Means ◽

Value Added ◽

Primary Source ◽

Common Disease ◽

Black Rot ◽

Crop Losses

New Zealand produces approximately 5,500 tonnes of brassica seed per year, two thirds of which, valued at $13M, is exported. Black rot caused by Xanthomonas campestris pv. campestris is a common disease of brassicas, and while crop losses are not extensive in New Zealand, internationally total crop losses have been reported. Seeds are the primary source of inoculum and the ease with which this inoculum spreads means that even small traces can cause severe epidemics. Genetic resistance to black rot is a complex trait which makes breeding for resistance in brassicas challenging. The effectiveness of chemical and cultural practices is variable. Biological control with natural antagonistic microbes may provide a more effective means of controlling black rot and other pests and diseases, and create opportunities for increasing the export value of brassica seed. Current cultural practices and the potential for biological control for the management of black rot are reviewed. Keywords: biocontrol, Brassicaceae, crucifer

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Biological control of tick populations: review and reflections

Cadernos de Saúde Pública ◽

10.1590/s0102-311x1994000100005 ◽

1994 ◽

Vol 10 (1) ◽

pp. 47-52 ◽

Cited By ~ 4

Author(s):

Norma V. Labarthe

Keyword(s):

Biological Control ◽

Genetic Selection ◽

Effective Vaccine ◽

Control Methods ◽

The Relationship ◽

Selection Of

This study is concerned with aspects of the relationship between ticks and their hosts that have a bearing on biological control of tick populations. It proposes control methods based on a program that would combine development of an effective vaccine with genetic selection of hosts.

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Isolation and Characterization of Midgut Symbiotic Bacteria from Tsetse Flies (G.Pallidipes) and Their Role in Biological Control Methods

International Journal of Research Studies in Biosciences ◽

10.20431/2349-0365.0709001 ◽

2019 ◽

Vol 7 (9) ◽

Keyword(s):

Biological Control ◽

Symbiotic Bacteria ◽

Tsetse Flies ◽

Control Methods ◽

Isolation And Characterization

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Biological Control Associated With Plant Nutrition for Meloidogyne javanica and Pratylenchus brachyurus Management in Soybean

Journal of Agricultural Science ◽

10.5539/jas.v12n1p149 ◽

2019 ◽

Vol 12 (1) ◽

pp. 149

Author(s):

Ana Paula Mendes Lopes ◽

Bruna Orlandini Toninato ◽

Mayra Renata Cruz Soares ◽

Cláudia Regina Dias-Arieira

Keyword(s):

Biological Control ◽

Plant Nutrition ◽

Aerial Part ◽

Integrated Management ◽

Meloidogyne Javanica ◽

Control Methods ◽

Pratylenchus Brachyurus ◽

Low Efficiency ◽

To Receive ◽

Nematode Mortality

Meloidogyne javanica and Pratylenchus brachyurus stand out among the main nematodes in soybean crops. Research on integrated management are often conducted, due to the low efficiency of the main control methods when they are applied alone. Thus, the aim of the present study was to assess the potential of biological control and plant nutrition products to control these nematodes in soybean. The effect of each product alone on nematode hatching and mortality was also assessed. A greenhouse experiment was also carried out, evaluating five doses of the product for biological control based on Bacillus and Trichoderma, with and without the presence of the product for nutrition, inoculated with 2000 eggs and juveniles for the gall nematode or 1000 specimens for the nematode lesions. After 30 days of multiplication, the aerial part was removed and the soil was revolved to receive the new sowing of the soybean with the respective treatments mentioned above. After 60 days, the experiments were evaluated for nematological parameters. Both products reduced hatching and increased nematode mortality. Treatments with biological control were efficient in reducing M. javanica and P. brachyurus, mainly when applied at doses close to 5 and 8 kg ha-1, respectively. The nutrition product negatively influences the biological control.

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