scholarly journals The biology of Canadian weeds. 132. Raphanus raphanistrum L.

2005 ◽  
Vol 85 (3) ◽  
pp. 709-733 ◽  
Author(s):  
Suzanne I Warwick ◽  
Ardath Francis

A review of biological information is provided for Raphanus raphanistrum L. Native to the Mediterranean region, the species is widely introduced and naturalized in temperate regions around the world. In Canada, it currently occurs in all provinces except Saskatchewan and Manitoba, has only a limited distribution in Alberta, and is also absent from the Yukon, the Northwest Territories and Nunavut. It is most abundant in the Atlantic and Pacific regions and is an important weed of field crops in the Maritime provinces and Quebec. A persistent seed bank, competitive annual growth habit and high fecundity all contribute to its weedy nature and ensure that it will be a continuing problem. It can easily hybridize with cultivated radish, R. sativus L., and commonly does so when they occur together. Limited hybridization with canola, Brassica napus L., has been reported from several experimental field and greenhouse trials. Selective herbicide control is most difficult in canola and other cruciferous crops. It is the most important dicot weed in the southwestern region of Australia, primarily due to the evolution of several different herbicide-resistant biotypes. These include biotypes resistant to the acetolactate synthase (ALS)-inhibitors (group 2 herbicides) and/or photosystem II-inhibitors (group 5), and a biotype with multiple resistance to ALS-inhibitors, photosystem II-inhibitors, an auxin (2,4-D amine), and a phytoene desaturase (PSDS)-inhibitor (diflufenican). A biotype resistant to the ALS-inhibiting herbicide chlorsulfuron has also been detected in South Africa. Key words: Wild radish, Raphanus raphanistrum, herbicide resistance, canola, hybridization, RAPRA

2002 ◽  
Vol 82 (4) ◽  
pp. 803-823 ◽  
Author(s):  
S. I. Warwick ◽  
A. Francis ◽  
D. J. Susko

An updated review of biological information is provided for Thlaspi arvense. Native to Eurasia, the species is naturalized and widely spread in temperate regions of the northern hemisphere, including all of Canada's provinces and territories, and has recently spread to temperate regions in the southern hemisphere. It is an annual pioneer of disturbed soils and is an important weed of grain, oilseed, and forage crops in Canada, particularly in the prairies. High levels of erucic acid and glucosinolates can contaminate canola. When present in hay or other fodder, its seeds or leaves can be toxic to animals, as well as contaminate milk and meat with unpleasant flavors. It can serve as a host for insect, nematode, fungal and viral pests of canola and mustard crops. A persistent seed bank, high fecundity, and the growth habit of a hardy winter annual with early- (EF) and late-flowering (LF) strains, all contribute to its ability to compete with crops. Effective herbicides include the sulfonylureas, chlorsulfuron and ethametsulphuron, MCPA, tribenuronmethyl, phenocyacetic acid, flurtamone, 2,4-D, 2,4-D + dicamba, and 2,4-D + picloram. A resistant biotype to Group 2 herbicides, which inhibit acetolactate synthase (ALS), has been found at two to five sites in Alberta in 2001. The potential of T. arvense as an industrial oilseed crop is being investigated. Key words: Stinkweed, Thlaspi arvense, weed biology, field pennycress, fanweed, oilseed potential


2011 ◽  
Vol 25 (3) ◽  
pp. 514-518 ◽  
Author(s):  
Patrick M. McMullan ◽  
Jerry M. Green

Seeds of a putative 4-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibiting herbicide–resistant tall waterhemp biotype from Henry County, IA, were collected from a seed corn field in fall 2009 after plants were not controlled following a POST application of mesotrione plus atrazine. The response of this biotype to various herbicide modes of action was evaluated in greenhouse and field tests. Under greenhouse conditions, the suspect biotype showed an eightfold decrease in sensitivity to mesotrione with a 50% control rate of 21 g ha−1compared with 2.7 g ha−1for the susceptible biotype. The biotype also had a 10-fold decrease in sensitivity to atrazine and a 28-fold decrease in sensitivity to thifensulfuron. Under field conditions, tall waterhemp was not controlled POST at the label rate of 1,100 g ha−1of atrazine. Tall waterhemp control was less than 60% at the label rates of three commonly used POST HPPD-inhibiting herbicides in seed corn: 105 g ha−1of mesotrione, 92 g ha−1of tembotrione, or 18 g ha−1of topramezone. Thus, this new tall waterhemp biotype is resistant to three herbicide modes of action: HPPD inhibitors, photosystem-II inhibitors, and acetolactate synthase (ALS) inhibitors.


2019 ◽  
Vol 37 ◽  
Author(s):  
A. FRANCISCHINI ◽  
J. CONSTANTIN ◽  
R.S. OLIVEIRA JR ◽  
H.K. TAKANO ◽  
R.R. MENDES

ABSTRACT: Herbicide resistance in Amaranthus genus occurs frequently around the word and has become a big problem in cotton producing areas. The objective of this work was to evaluate cross-and multiple-resistance of redroot pigweed (A. retroflexus) to herbicides used in preemergence in cotton fields in Brazil. Seven dose-response experiments were conducted with herbicides atrazine, prometryn, diuron, S-metolachlor, trifluralin, trifloxysulfuron-sodium and pyrithiobac-sodium, and the treatments consisted of application rates of 0, ¼, ½, 1, 2 and 4 times the recommended label rate. Eight A. retroflexus byotipes with suspect of resistance were sampled for experiments in three brazilian states of cotton producing. Resistance to prometryn was confirmed for one biotype in Goiás (GO), and one biotype from Mato Grosso (MT) showed cross-resistance to atrazine and prometryn. One byotipe from GO was identified with cross-resistance to trifloxysulfuron-sodium and pyrithiobac-sodium. One of the GO samples was identified with multiple resistance to prometryn and ALS inhibitors, another one to atrazine and ALS inhibitors, while MT byotipe was confirmed with multiple resistance to triazines and pyrithiobac. The herbicides S-metolachlor, diuron, and trifluralin were efficient for control of this species, therefore, they can be used as managment alternative in those regions.


2003 ◽  
Vol 83 (2) ◽  
pp. 441-451 ◽  
Author(s):  
A. Francis ◽  
S. I. Warwick

A review of biological information is provided for Neslia paniculata. Native to central Eurasia, this species is naturalized in other temperate regions of the northern hemisphere. In North America it is most abundant in Canada’s prairie provinces, but has spread west and north to British Columbia, Alaska, Yukon and the Northwest Territories, and to scattered locations in eastern Canada and the northern United States. It is typically a summer annual weed of disturbed soils. Its growth habit and persistence in the seed bank have enabled it to spread as an adventive and to maintain its presence in cultivated areas. While it is present in relatively low frequency as a weed in most crops, its indehiscent seed pods can contaminate harvested crops and spread in seed commodities. The small size of its seed pods and the similarity of its seeds to those of canola and condiment mustard have led to its regulation as a significant contaminant of commercial seed. It is generally well controlled by herbicides (e.g., sulfonylureas, glyphosate, MCPA, bromoxynil, and 2, 4-D); however, a population resistant to metsulfuron-methyl, one of the Group 2 herbicides that inhibit acetolactate synthase (ALS), was found at a site in Alberta in 1998. Key words: Ball mustard, Neslia paniculata, weed biology, herbicide resistance, seed contaminant


2002 ◽  
Vol 82 (2) ◽  
pp. 463-471 ◽  
Author(s):  
H. J. Beckie ◽  
A. G. Thomas ◽  
F. C. Stevenson

The nature and occurrence of herbicide resistance in wild oat in annual crops grown in the Grassland and Parkland regions of Saskatchewan were determined in a systematic survey of fields in two townships in 1997. The survey found that over one-half of fields in both townships had populations resistant to Group 1 [acetyl-CoA carboxylase (ACCase) inhibitors], Group 2 [acetolactate synthase (ALS) inhibitors], and/or Group 8 (e.g., triallate, difenzoquat) herbicides. Forty-three percent of fields in the Grassland township and 48% of fields in the Parkland township had Group 1-resistant (HR) wild oat; 30 and 17% of fields in the Grassland and Parkland township, respectively, had populations exhibiting Group 2 resistance, whereas about 15% of fields in both townships had Group 8-HR wild oat. Single- (Groups 1, 2, or 8) and multiple-group resistance (1, 2; 1, 8; 2, 8; 1, 2, 8) were exhibited in populations in fields in both townships. Frequency of occurrence of resistance was not generally affected by farm size. The nature of resistance in wild oat populations is more diverse, differences in distribution and abundance of HR wild oat biotypes between Grassland and Parkland regions are generally less apparent, and occurrence of resistance is more prevalent than documented previously. Key words: Avena fatua, herbicide resistance, survey


2019 ◽  
Vol 99 (3) ◽  
pp. 364-370
Author(s):  
Lauren Benoit ◽  
Nader Soltani ◽  
David C. Hooker ◽  
Darren E. Robinson ◽  
Peter H. Sikkema

Waterhemp is a competitive, summer annual, broadleaf weed that poses a considerable threat to Ontario grain farmers. Populations with multiple resistance to Group 2 (ALS-inhibitors), Group 5 (photosystem II inhibitors), and Group 9 (EPSPS inhibitors) herbicides have been confirmed in Ontario. If left uncontrolled, waterhemp competition can result in corn yield losses of up to 74%. The objective of this research was to evaluate preemergence (PRE) and postemergence (POST) herbicides for control of multiple-herbicide resistant (MR) waterhemp. Two field studies at two locations (Cottam and Walpole Island) were conducted in 2016 and 2017. Fifteen PRE and 12 POST herbicides were evaluated for waterhemp control, density, and aboveground biomass and corn yield. At 8 wk after application (WAA), S-metolachlor/mesotrione/atrazine (1393/139/524 g a.i. ha−1) and S-metolachlor/mesotrione/bicyclopyrone/atrazine (1259/140/35/588 g a.i. ha−1) applied PRE were the most efficacious, controlling MR waterhemp 87% and 91%, respectively. At 8 WAA, the most efficacious POST herbicides were mesotrione + atrazine and dicamba/atrazine, controlling MR waterhemp 92% and 87%, respectively. Reduced waterhemp interference with the PRE herbicides evaluated resulted in corn yield that was similar to the weed-free control.


2000 ◽  
Vol 80 (4) ◽  
pp. 939-961 ◽  
Author(s):  
Suzanne I. Warwick ◽  
Hugh J. Beckie ◽  
A. Gordon Thomas ◽  
Tracey McDonald

An updated review of biological information is provided for Sinapis arvensis L. Native to the Old World, the species is widely introduced and naturalized in temperate regions around the world. The species occurs in all the provinces, the Northwest Territories, and the Yukon. It is an important weed of field crops in the Canadian prairies. A strongly persistent seedbank, competitive annual growth habit and high fecundity all contribute to its weedy nature and ensure that it will be a continuing problem. Several cases of herbicide resistance have been documented for natural populations of S. arvensis in Canada, including biotypes resistant to: i) Group 2 herbicides, which inhibit acetolactate synthase (ALS), from Manitoba in 1992 and Alberta in 1993; ii) Group 4 herbicides or synthetic auxins from Manitoba in 1991; and iii) Group 5 herbicides, which inhibit photosynthesis at photosystem II, from Ontario in 1983. The species is a close relative of Brassica nigra (L.) Koch, black mustard, and is capable of limited genetic exchange with the Brassica crop species under laboratory hybridization conditions either by conventional crossing or with the aid of ovary/embryo recovery techniques. Key words: Wild mustard, Sinapis arvensis, weed biology, herbicide resistance, risk assessment


Author(s):  
P. Bagavandoss ◽  
JoAnne S. Richards ◽  
A. Rees Midgley

During follicular development in the mammalian ovary, several functional changes occur in the granulosa cells in response to steroid hormones and gonadotropins (1,2). In particular, marked changes in the content of membrane-associated receptors for the gonadotropins have been observed (1).We report here scanning electron microscope observations of morphological changes that occur on the granulosa cell surface in response to the administration of estradiol, human follicle stimulating hormone (hFSH), and human chorionic gonadotropin (hCG).Immature female rats that were hypophysectcmized on day 24 of age were treated in the following manner. Group 1: control groups were injected once a day with 0.1 ml phosphate buffered saline (PBS) for 3 days; group 2: estradiol (1.5 mg/0.2 ml propylene glycol) once a day for 3 days; group 3: estradiol for 3 days followed by 2 days of hFSH (1 μg/0.1 ml) twice daily, group 4: same as in group 3; group 5: same as in group 3 with a final injection of hCG (5 IU/0.1 ml) on the fifth day.


Author(s):  
D. J. McComb ◽  
N. Ryan ◽  
E. Horvath ◽  
K. Kovacs ◽  
E. Nagy ◽  
...  

Conventional light and electron microscopic techniques failed to clarify the cellular composition and derivation of spontaneous and induced, intrasellar and transplanted pituitary adenomas in rats (1). In the present work, electron microscopic immunocytochemistry was applied to evaluate five adenohypo-physial tumors using a technique described by Moriarty and Garner (2). Spontaneously occurring pituitary adenomas (group 1) were harvested from aging female Long-Evans rats. R-Amsterdam rats were treated with 2 x 1.0 mg estrone acetate (HogivaI) s.c. weekly for 6 months. Pituitary adenomas in excess of 30 mg were removed from these animals to make up the tumors of group 2. Groups 3 and 4 consisted of estrogen-induced autonomous transplan¬ted pituitary tumors MtT.WlO and MtT.F4. Group 5 was a radiation-induced transplanted autonomous pituitary tumor MtT.W5. The tumors of groups 3,4 and 5 were allowed to proliferate in host rats 6-8 weeks prior to removal for processing. Tissue was processed for transmission electron microscopy (glutaraldehyde fixation, OsO4 postfixation and epoxy resin embedding), and electron microscopic immunocytochemistry (3% paraformaldehyde fixation and Araldite embedding).


Author(s):  
Mustafa Salah Hasan ◽  
Ayman Barzan Abdulgafor ◽  
Maher Saber Owain ◽  
Mohammed Ali Hussein ◽  
Qusay Mohammed Aboud ◽  
...  

This study aimed to evaluate the liver, kidney damage caused by S. typhimurium and to estimate the oxidative damage in association with this bacteria. A highly virulent isolates of S. typhimurium were obtained from the department of internal and preventive medicine/ College of Veterinary Medicine/ University of Baghdad. A twenty five local rabbits of both genders with age range (2-4 months) weeks old were used for this study, the rabbits were divided randomly into five groups each group contains 5 rabbits :- group 1: drenched orally with 5 ml of normal saline and consider as control group, group 2: were drenched orally with (5 ml) suspension which contain (5��109 CFU) of Salmonella typhimurium and regarded as infected group, group 3 were drenched orally with (5 ml) suspension which have (5��109 CFU) of Salmonella typhimurium then treated with a single dose of gentamicin alone at 0.05ml/kg (5mg/ml) orally after presence of signs (after 24hrs. post inoculation), group 4 were drenched (5 ml) suspension having (5��109 CFU) of Salmonella typhimurium then treated with a single dose of Ca-EDTA alone at 40mg/kg orally after presence of signs (after 24hrs. post inoculation) and group 5 were drenched (5 ml) suspension that contain (5��109 CFU) of Salmonella typhimurium then treated with a single dose of combined gentamicin at 0.05ml/kg (5mg/ml) orally after presence of signs (after 24hrs. post inoculation) and Ca-EDTA 40mg/kg after presence of signs (after 24hrs. post inoculation).The results of biochemical profile showed a significant increase (p less than 0.05) in ALT, creatinine and urea levels in infected group as compared with control group, while, the treated groups especially group 5 showed a significant improvement in ALT, Urea and creatinine levels which returned to relative normal levels as compared with infected group after 96hrs. post treatment. Also, the results of oxidative stress showed a significant increase in the levels of MDA in G2, G3, G4 and G5 after 48 hrs. post treatment, while the level of GSH showed a significant decrease in the level at 48hrs., both were returned to relative normal levels after 96hrs.post treatment especially in group 5.In conclusion, S. typhimurium can causing liver and kidney damage which is manifested by increase ALT, Urea and Creatinine. Also, MDA and GSH is increased due to salmonellosis.


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