scholarly journals A linuron-free weed management strategy for carrots

2019 ◽  
Vol 33 (03) ◽  
pp. 464-474
Author(s):  
Tessa de Boer ◽  
Peter Smith ◽  
Kevin Chandler ◽  
Robert Nurse ◽  
Kristen Obeid ◽  
...  
Keyword(s):  
Effective Dose ◽  
Pest Management ◽  
Weed Management ◽  
Management Strategy ◽  
Seedling Emergence ◽  
Growing Season ◽  
Field Trials ◽  
Organic Soils ◽  
Biologically Effective Dose ◽  
And Control

AbstractThe development of a linuron-free weed management strategy for carrot production is essential as a result of the herbicide reevaluation programs launched by the Pest Management Regulatory Agency in Canada for herbicides registered before 1995 and the discovery of linuron-resistant pigweed species in Ontario. Field trials were conducted in one of Ontario’s main carrot-growing regions on high organic soils in 2016 and 2017. Pigweed species seedlings were effectively controlled with PRE treatments of prometryn, pendimethalin, S-metolachlor, or glufosinate. POST treatments of pyroxasulfone and metribuzin followed by predetermined biologically effective dose (≥90% control of pigweed seedlings) of acifluorfen, oxyfluorfen, fluthiacet-methyl, and fomesafen achieved excellent crop selectivity and commercially acceptable pigweed species seedling control under field conditions. Carfentrazone-ethyl or fomesafen applied PRE severely reduced seedling emergence and yield in the wet growing season of 2017. This study demonstrated clearly that an alternative linuron-free strategy can be developed for carrots. The strategy of exploring the potential to use the biologically effective dose of selected herbicides to achieve crop selectivity and control of pigweed species seedlings was verified.

Seed production and seedbank dynamics in subthreshold velvetleaf (Abutilon theophrasti) populations

Weed Science ◽  
1997 ◽  
Vol 45 (1) ◽  
pp. 85-90 ◽  
Author(s):  
John Cardina ◽  
Heather M. Norquay
Keyword(s):  
Pest Management ◽  
Seed Production ◽  
Weed Management ◽  
Seedling Emergence ◽  
Seed Rain ◽  
Abutilon Theophrasti ◽  
No Tillage ◽  
Single Seed ◽  
No Till ◽  
The Impact

The impact of seed production by subthreshold weed populations on future weed problems has impeded the adoption of integrated pest-management principles for weed management. Studies were conducted in fields with no velvetleaf history to determine how seedbanks and seedling populations change following seed production 1 yr or 5 consecutive yr in plow-disk and no-tillage corn. Cumulative seed production by 0.19 velvetleaf plants m−2increased in a linear fashion from 1989 to 1994, with annual additions averaging from 330 seeds m−2for velvetleaf in corn to 2,500 seeds m−2for velvetleaf without competition from corn. Five-year cumulative seed production was 1,480 seeds m−2in plow-disk and 1,810 seeds m−2in no-till corn. In no-till corn, 42 velvetleaf seedlings m−2emerged the 1st year after the 1989 seed rain, but only 35 seedlings m−2emerged over the next 4 yr. In plow-disk plots, annual emergence averaged 12 seedlings m−2. Five years after the 1989 seed rain, the proportion of seeds lost to emergence was about 20% in both tillage treatments. Where velvetleaf seeds were allowed to return to the soil every year, cumulative seedling emergence was lower in plow-disk than in no-till corn, with total emergence of 70 and 360 seedlings m−2, respectively, after 5 yr. Seedbank numbers ranged from 10 seeds m−25 yr after a single seed rain (290 seeds m−2) by velvetleaf in plow-disk corn to 1,020 seeds m−2following 5 consecutive yr of seed rain where 12,580 seeds m−2were returned without corn competition in no-till. Seedbank samples in the fall of the 5th year had 69 to 98% fewer seeds than were accounted for by cumulative seed rain and seedling emergence, with greater apparent seed losses in plow-disk corn than in no-till corn. Over 90% velvetleaf control would be required annually to maintain subthreshold populations for 5 yr following a single seed rain. By comparison, over 95% control would be required annually to maintain subthreshold populations where velvetleaf seed return is permitted each year.

Tolpyralate Efficacy: Part 1. Biologically Effective Dose of Tolpyralate for Control of Annual Grass and Broadleaf Weeds in Corn

2018 ◽  
Vol 32 (6) ◽  
pp. 698-706 ◽  
Author(s):  
Brendan A. Metzger ◽  
Nader Soltani ◽  
Alan J. Raeder ◽  
David C. Hooker ◽  
Darren E. Robinson ◽  
...  
Keyword(s):  
Effective Dose ◽  
Weed Management ◽  
Field Studies ◽  
Biologically Effective Dose ◽  
Limited Information ◽  
Weed Species ◽  
Common Lambsquarters ◽  
Wild Mustard ◽  
Low Field ◽  
Green Foxtail

AbstractTolpyralate is a new 4-hydroxyphenyl-pyruvate dioxygenase (HPPD)-inhibiting herbicide for POST weed management in corn; however, there is limited information regarding its efficacy. Six field studies were conducted in Ontario, Canada, over 3 yr (2015 to 2017) to determine the biologically effective dose of tolpyralate for the control of eight annual weed species. Tolpyralate was applied POST at six doses from 3.75 to 120 g ai ha−1and tank mixed at a 1:33.3 ratio with atrazine at six doses from 125 to 4,000 g ha−1. Regression analysis was performed to determine the effective dose (ED) of tolpyralate, and tolpyralate+atrazine, required to achieve 50%, 80%, or 90% control of eight weed species at 1, 2, 4, and 8 wk after application (WAA). The ED of tolpyralate for 90% control (ED90) of velvetleaf, common lambsquarters, common ragweed, redroot pigweed or Powell amaranth, and green foxtail at 8 WAA was ≤15.5 g ha−1; however, tolpyralate alone did not provide 90% control of wild mustard, barnyardgrass, or ladysthumb at 8 WAA at any dose evaluated in this study. In contrast, the ED90for all species in this study with tolpyralate+atrazine was ≤13.1+436 g ha−1, indicating that tolpyralate+atrazine can be highly efficacious at low field doses.

scholarly journals MYCOTOXIN PREVENTION AND CONTROL IN LINSEED

2007 ◽  
Vol 1 ◽  
pp. 162
Author(s):  
Elvyra Gruzdevienè ◽  
Audroné Mankevičienè
Keyword(s):  
Ochratoxin A ◽  
Prevention And Control ◽  
Growing Season ◽  
Field Trials ◽  
Seed Sample ◽  
Flax Seed ◽  
Moisture Control ◽  
Mycotoxin Contamination ◽  
And Control ◽  
Blue Chip

The present paper analyses mycotoxin contamination in six oil flax seed of the flax varieties differing in the length of the growing season. The flax seed grown in precision field trials was analyzed for mycotoxin contamination at harvesting and during storage period.The analyses done at harvesting revealed the traces of aflatoxin were identified only in the seed samples of cvs. Lu-5 and Gold Merchant, while those of ochratoxin A (2.3 µg kg'1) in the seed sample of cv. Szaphir. All the seed samples tested were found positive for DON contamination, except for cv. Blue Chip, but the levels identified were very low. After 8 months of storage the levels of aflatoxin and ochratoxin A. in flax seed samples increased. Mycotoxin increasing immediately concerned with seed fungi contamination. These indicators could be determining by moisture control such as seed drying.

scholarly journals Spread of Chilean needle grass (Nassella neesiana) in Marlborough New Zealand

2006 ◽  
Vol 59 ◽  
pp. 266-270 ◽  
Author(s):  
M. Bell
Keyword(s):  
Land Use ◽  
New Zealand ◽  
Pest Management ◽  
Land Management ◽  
Management Strategy ◽  
Land Use Changes ◽  
Management Plan ◽  
Effective Control ◽  
And Control

Chilean needle grass (Nassella neesiana) is a containment pest in the Regional Pest Management Strategy for Marlborough It is of concern because it has sharptipped seeds that bore into the eyes and pelts of livestock Discovered in Marlborough in the 1930s it now infests 4311 ha In 1987 18 properties were infested increasing to 53 by 2000 and 96 by December 2005 In addition both the range and density of Chilean needle grass has increased significantly since 1987 and to date no infestations have been eradicated Failure to stop this spread is due to the difficulty of both identification and control Effective control and land management methods for this weed are urgently needed The probability of this weed spreading further both within and beyond Marlborough appears to be high This conclusion along with land use changes has implications for the review of the Regional Pest Management Plan

Farmers’ knowledge, perceptions and practices in jute insect pest management and cultural strategy in the upper Gangetic plains of West Bengal, India

2017 ◽  
Vol 51 (04) ◽  
Author(s):  
Abdul Sadat ◽  
Kaushik Chakraborty
Keyword(s):  
Pest Management ◽  
Management Strategy ◽  
Yield Loss ◽  
West Bengal ◽  
Insect Pests ◽  
Insect Pest ◽  
Control Cost ◽  
Gangetic Plains ◽  
And Control ◽  
Damage Symptoms

A survey on jute farmers’ knowledge, perceptions and practices (KPP) in pest management strategy was conducted during jute cultivation season of 2015 in the upper Gangetic plains of Uttar Dinajpur District, West Bengal, India. Detection and control of insect pests was largely based on damage symptoms of host plant. Damage caused by jute semilooper (Anomis sabulifera) was often mistakenly attributed to other leaf feeding caterpillars. Nearly all of the farmers applied insecticides (99%) without target specific use with an average 1.5 per season which may increase up to two to three spray per week. Pyrethroids were mostly accepted insecticide (67%), followed by organophosphates (33%) without knowing its toxic effect on environment. Farmers’ estimated yield loss due to insect pests was significantly correlated to estimated pest control cost. Due to pesticide sellers’ recommendations, farmer’s insecticidal ‘spray load’ significantly increased in every year, whereas the adopted number of insecticidal increased with advice following the guidance of extension staff and advertisement. Expenditure for pesticides was in concurrent with that of fertilizers. Only 10% of participating farmers knew about natural enemies, all of which were predators. Investigation is needed to evaluate whether significant savings can be obtained given a more judicious use of pesticides.

Seedbank Dynamics of Two Swallowwort (Vincetoxicum) Species

2017 ◽  
Vol 10 (2) ◽  
pp. 136-142 ◽  
Author(s):  
Antonio DiTommaso ◽  
Lindsey R. Milbrath ◽  
Scott H. Morris ◽  
Charles L. Mohler ◽  
Jeromy Biazzo
Keyword(s):  
United States ◽  
Management Strategy ◽  
Seedling Emergence ◽  
Soil Surface ◽  
Growing Season ◽  
First Year ◽  
Northeastern United States ◽  
The Third ◽  
Viable Seeds ◽  
Filled Seeds

Pale swallowwort and black swallowwort are European viny milkweeds that have become invasive in many habitats in the northeastern United States and southeastern Canada. A multiyear seedbank study was initiated in fall 2011 to assess annual emergence of seedlings and longevity of seeds of pale swallowwort and black swallowwort at four different burial depths (0, 1, 5, and 10 cm) over 4 yr. One hundred swallowwort seeds were sown in seed pans buried in individual pots, and emerged seedlings were counted and removed from May through September each year. A subset of seed pans was retrieved annually in October, and recovered seeds were counted and tested for viability. The majority of seedling emergence occurred during the first year (92% in 2012), and no new seedlings emerged in the third (2014) or fourth (2015) years. Pale swallowwort had relatively poor emergence at sowing depths of 0 cm (11%), 5 cm (6%), and 10 cm (0.05%—only one seedling), while 37% of pale swallowwort seeds emerged at 1 cm. The larger-seeded black swallowwort was more successful, with two-thirds of all sown seeds emerging at depths of 1 cm (71%) and 5 cm (66%), and 26% emerging at 10 cm. Only 16% of the surface-sown black swallowwort emerged. A large portion of the seeds that germinated at 10 cm, as well as at 5 cm for pale swallowwort, died before reaching the soil surface. Of filled seeds that were recovered in 2012 (black swallowwort at the 0-cm depth), 66% were viable. No viable seeds were recovered after the second growing season. Seeds recovered following the third year had become too deteriorated to accurately assess. Swallowwort seeds do not appear to survive more than 2 yr in the soil, at least in our experiment, suggesting that the elimination of seed production over 3 yr will exhaust the local seedbank. Seeds would need to be buried at least 10 cm for pale swallowwort but more than 10 cm for black swallowwort to prevent seedling emergence. Burial of swallowwort seeds as a management strategy may, however, only be practical in natural areas where high swallowwort densities occur.

Effects of soil-borne Rhizoctonia solani on canola seedlings after application of glyphosate herbicide

2013 ◽  
Vol 93 (1) ◽  
pp. 97-107 ◽  
Author(s):  
A. Rashid ◽  
S. F. Hwang ◽  
H. U. Ahmed ◽  
G. D. Turnbull ◽  
S. E. Strelkov ◽  
...  
Keyword(s):  
Rhizoctonia Solani ◽  
Weed Management ◽  
Management Practice ◽  
Seedling Emergence ◽  
Dry Weight ◽  
Field Trials ◽  
Shoot Dry Weight ◽  
Subsequent Crop ◽  
Glyphosate Herbicide ◽  
The Impact

Rashid, A., Hwang, S. F., Ahmed, H. U., Turnbull, G. D., Strelkov, S. E. and Gossen, B. D. 2013. Effects of soil-borne Rhizoctonia solani on canola seedlings after application of glyphosate herbicide. Can. J. Plant Sci. 93: 97–107. Application of glyphosate (N-phosphonomethyl glycine) prior to seeding is a common weed management practice in many agricultural systems. However, there are concerns that this practice may increase the impact of soil-borne diseases on the crop, even in cultivars that are resistant to glyphosate. In the current study, the effects of pre-plant applications of glyphosate on seedling blight of canola caused by Rhizoctonia solani and subsequent crop growth were examined under field and greenhouse conditions. Under greenhouse conditions in soil inoculated with R. solani, glyphosate application 15 d before seeding reduced seedling emergence, increased damping-off, and decreased plant height and shoot dry weight of canola relative to a glyphosate-free control. However, the adverse effects were substantially reduced when the crop was seeded 33 d after glyphosate application. This indicates that glyphosate application prior to planting may increase the impact of R. solani on canola seedlings, but that this effect diminishes quite rapidly. Soil populations of R. solani declined over the 33-d period regardless of glyphosate treatment. Glyphosate application 10 d before seeding increased seedling emergence and seed yield (1 of 2 yr) of canola in field trials inoculated with R. solani.

Biologically effective dose of glyphosate as influenced by weed size in corn

2016 ◽  
Vol 96 (3) ◽  
pp. 455-460 ◽  
Author(s):  
Nader Soltani ◽  
Robert E. Nurse ◽  
Peter H. Sikkema
Keyword(s):  
Effective Dose ◽  
Weed Control ◽  
Field Trials ◽  
Biologically Effective Dose ◽  
Limited Information ◽  
Weed Species ◽  
Common Ragweed ◽  
Time Of Application ◽  
Green Foxtail ◽  
Lamb’S Quarters

There is limited information on the effect of weed size at the time of application on glyphosate efficacy in Ontario. Eleven field trials were conducted over a 3 yr period (2010–2012) in Ontario to determine the biologically effective dose of glyphosate applied postemergence (POST) in corn at doses of 112.5–1350 g acid equivalent (a.e.) ha−1 for the control of various grass and broadleaved weed species when the weeds were 10, 20 or 30 cm in height. The GR90 for redroot pigweed, common ragweed, common lamb’s-quarters, barnyardgrass, and green foxtail were 353, 630, 621, 763, and <112.5 g a.e. ha−1 when applied at 10 cm weed height, 235, 201, 906, 868, and 296 g a.e. ha−1 when applied at 20 cm weed height, and 792, >1350, >1350, 912, and 675 g a.e. ha−1 when applied at 30 cm weed height, respectively. Corn yields were maximized when glyphosate was applied to weeds that were up to 10 cm in height, but was reduced with later glyphosate application timings. The results of this study reinforce the importance of early POST weed control in corn.

Efficacy of Tiafenacil Applied Preplant Alone or Mixed with Metribuzin for Glyphosate-Resistant Horseweed Control in Soybean

2021 ◽  
pp. 1-21
Author(s):  
David B. Westerveld ◽  
Nader Soltani ◽  
David C. Hooker ◽  
Darren E. Robinson ◽  
Peter H. Sikkema
Keyword(s):  
Effective Dose ◽  
Management Strategy ◽  
Field Experiments ◽  
Biologically Effective Dose ◽  
Potential Utility ◽  
Industry Standard ◽  
No Till ◽  
Industry Standards ◽  
Herbicide Treatments ◽  
Chemical Class

Abstract Tiafenacil is a recently developed protoporphyrinogen IX oxidase (PPO)-inhibiting herbicide from the pyrimidinedione chemical class that is proposed for use as a preplant (PP) burndown in soybean. Glyphosate-resistant (GR) horseweed is a troublesome weed often found in no-till systems that can dramatically reduce soybean yield; control in soybean has been variable. Five field experiments were conducted over 2019 and 2020 in commercial soybean fields with GR horseweed to determine the biologically-effective-dose (BED) of tiafenacil and tiafenacil + metribuzin, and to compare their efficacy to currently accepted industry standard herbicide treatments in identity-preserved (IP, non-GMO), GR, and glyphosate/dicamba-resistant (GDR) soybean systems. There was no soybean injury with treatments evaluated. The calculated doses of tiafenacil for 50, 80, and 95% control of GR horseweed control were 21, 147 and >200 g ai ha−1, respectively, at 8 weeks after application (WAA). Lower doses were calculated with the addition of metribuzin (400 g ai ha−1) to tiafenacil for 50 and 80% control, with no dose of tiafenacil + metribuzin providing 95% control. Tiafenacil + metribuzin at 25 + 400 and 50 + 400 g ai ha−1 controlled GR horseweed 88 and 93% , respectively which was similar to the industry standards of saflufenacil + metribuzin (25 + 400 g ai ha−1) and glyphosate/dicamba + saflufenacil (1200/600 + 25 g ai ha−1) that provided 98 to 100% control, respectively at 8 WAA. This study presents the potential utility of tiafenacil + metribuzin as a GR horseweed management strategy in soybean.

Glyphosate-resistant Canada fleabane [Conyza canadensis (L). Cronq.]: Dose response to glyphosate and control with postemergence herbicides in soybean in Ontario

2013 ◽  
Vol 93 (6) ◽  
pp. 1187-1193 ◽  
Author(s):  
Holly P. Byker ◽  
Nader Soltani ◽  
Darren E. Robinson ◽  
François J. Tardif ◽  
Mark B. Lawton ◽  
...  
Keyword(s):  
Effective Dose ◽  
Dose Response ◽  
Yield Loss ◽  
Field Studies ◽  
Conyza Canadensis ◽  
Biologically Effective Dose ◽  
Soybean Yield ◽  
And Control ◽  
Postemergence Herbicides

Byker, H. P., Soltani, N., Robinson, D. E., Tardif, F. J., Lawton, M. B. and Sikkema, P. H. 2013. Glyphosate-resistant Canada fleabane [ Conyza canadensis (L). Cronq.]: Dose response to glyphosate and control with postemergence herbicides in soybean in Ontario. Can. J. Plant Sci. 93: 1187–1193. Glyphosate-resistant (GR) Canada fleabane was first reported in Ontario in 2010. Twelve field studies were conducted over a 2-yr period (2011, 2012) to determine the biologically effective dose of glyphosate in the field and to determine the efficacy of postemergence herbicides for control of GR Canada fleabane. A dose between 1271 and 5652 g a.e. ha−1 was required for a 50% reduction in Canada fleabane biomass depending on site and year. To achieve acceptable (>95%) control with glyphosate, 18 840 to 43 200 g a.e. ha−1 of glyphosate was required across all sites. Therefore application of glyphosate at these doses for acceptable (>95%) control is not economical. None of the postemergence herbicides labeled for use in soybean provided acceptable (>95%) control, with cloransulam providing the greatest control (67%) 4 wk after application. Therefore, GR Canada fleabane must be controlled prior to soybean emergence as current herbicides registered in soybean for postemergence use do not provide sufficient control to prevent soybean yield loss.

Sign in / Sign up

Export Citation Format

Share Document