scholarly journals Resistance to post-emergent herbicides is becoming common for grass weeds on New Zealand wheat and barley farms

PLoS ONE ◽  
2021 ◽  
Vol 16 (10) ◽  
pp. e0258685
Author(s):  
Christopher E. Buddenhagen ◽  
Trevor K. James ◽  
Zachary Ngow ◽  
Deborah L. Hackell ◽  
M. Phil Rolston ◽  
...  
Keyword(s):  
New Zealand ◽  
Ad Hoc ◽  
Acetolactate Synthase ◽  
Stellaria Media ◽  
Herbicide Resistant ◽  
The North ◽  
Mother Plants ◽  
Als Inhibitors ◽  
Als Inhibitor ◽  
North And South

To estimate the prevalence of herbicide-resistant weeds, 87 wheat and barley farms were randomly surveyed in the Canterbury region of New Zealand. Over 600 weed seed samples from up to 10 mother plants per taxon depending on abundance, were collected immediately prior to harvest (two fields per farm). Some samples provided by agronomists were tested on an ad-hoc basis. Over 40,000 seedlings were grown to the 2–4 leaf stage in glasshouse conditions and sprayed with high priority herbicides for grasses from the three modes-of-action acetyl-CoA carboxylase (ACCase)-inhibitors haloxyfop, fenoxaprop, clodinafop, pinoxaden, clethodim, acetolactate synthase (ALS)-inhibitors iodosulfuron, pyroxsulam, nicosulfuron, and the 5-enolpyruvyl shikimate 3-phosphate synthase (EPSPS)-inhibitor glyphosate. The highest manufacturer recommended label rates were applied for the products registered for use in New Zealand, often higher than the discriminatory rates used in studies elsewhere. Published studies of resistance were rare in New Zealand but we found weeds survived herbicide applications on 42 of the 87 (48%) randomly surveyed farms, while susceptible reference populations died. Resistance was found for ALS-inhibitors on 35 farms (40%) and to ACCase-inhibitors on 20 (23%) farms. The number of farms with resistant weeds (denominator is 87 farms) are reported for ACCase-inhibitors, ALS-inhibitors, and glyphosate respectively as: Avena fatua (9%, 1%, 0% of farms), Bromus catharticus (0%, 2%, 0%), Lolium spp. (17%, 28%, 0%), Phalaris minor (1%, 6%, 0%), and Vulpia bromoides (0%, not tested, 0%). Not all farms had the weeds present, five had no obvious weeds prior to harvest. This survey revealed New Zealand’s first documented cases of resistance in P. minor (fenoxaprop, clodinafop, iodosulfuron) and B. catharticus (pyroxsulam). Twelve of the 87 randomly sampled farms (14%) had ALS-inhibitor chlorsulfuron-resistant sow thistles, mostly Sonchus asper but also S. oleraceus. Resistance was confirmed in industry-supplied samples of the grasses Digitaria sanguinalis (nicosulfuron, two maize farms), P. minor (iodosulfuron, one farm), and Lolium spp. (cases included glyphosate, haloxyfop, pinoxaden, iodosulfuron, and pyroxsulam, 9 farms). Industry also supplied Stellaria media samples that were resistant to chlorsulfuron and flumetsulam (ALS-inhibitors) sourced from clover and ryegrass fields from the North and South Island.

scholarly journals The application of 1.8-naphthalic anhydride to control ALS-herbicide resistant barnyardgrass with graminicides

2020 ◽  
pp. 4-9
Author(s):  
V. Schwartau ◽  
L. Mykhalska
Keyword(s):  
Chemical Control ◽  
Mitotic Cycle ◽  
Acetolactate Synthase ◽  
Acetyl Coa Carboxylase ◽  
Naphthalic Anhydride ◽  
Herbicide Resistant ◽  
Rice Plants ◽  
Als Inhibitors ◽  
Aseptic Conditions ◽  
Als Inhibitor

Goal. Investigate the possibility to use 1,8-naphthalic anhydride metabolism inductor to control acetolactate synthase (ALS) inhibitor-resistant biotype of common graminicides of aryloxyphenoxypropionic acid class in rice. Methodology. The interaction of 1,8-naphthalic anhydride and fenoxaprop-p-ethyl on variety Vikont rice plants was studied under laboratory aseptic conditions. The data were statistically processed. Results. In Ukraine we have identified the biotype of resistant to herbicide ALS inhibitors Echinochloa crus-galli, which is cross-resistant to widely used herbicides — ALS inhibitors of the following chemical classes: imidazolinones (imazamox, imazapyr), sulfonylurea (nicosulfuron), triazolopyrimidines (penoxsulam). The possibilities of chemical control of weeds in rice, corn, sunflower, etc. crops are significantly limited. Multi-resistance of this weed biotype to herbicides — inhibitors of photosynthesis, mitotic cycle, 5-enolpyruvylshikimate-3-phosphate synthase, acetyl-CoA-carboxylase, protein synthesis — has not been detected. Therefore, the use of graminicides of aryloxyphenoxypropionate class is promising for the control of this ALS-resistant biotype of Echinochloa crus-galli. To increase the selectivity of fenoxaprop-P-ethyl application to rice plants, we propose to treat the seeds of the crop with the inductor of xenobiotics metabolism in plants — 1.8-naphthalic anhydride before sowing. When using 1.8-naphthalic anhydride in concentrations of 10-5 M, phytotoxicity of fenoxaprop-P-ethyl in concentrations of 10-6 and 10-5 M to rice plants is effectively reduced. Conclusions. The use of 1.8-naphthalic anhydride is promising for increasing the selectivity of fenoxaprop-P-ethyl for rice plants and allows the development of technologies using graminicides of aryloxyphenoxypropionate class to control ALS-resistant biotype of Echinochloa crus-galli in crops. Also, it is necessary to pay attention to the problem of ALS-resistant weed biotype proliferation control in agrophytocenoses in regions of Ukraine.

Multiple herbicide-resistant Palmer amaranth (Amaranthus palmeri) in Connecticut: confirmation and response to POST herbicides

2021 ◽  
pp. 1-7
Author(s):  
Jatinder S. Aulakh ◽  
Parminder S. Chahal ◽  
Vipan Kumar ◽  
Andrew J. Price ◽  
Karl Guillard
Keyword(s):  
Cropping Systems ◽  
Acetolactate Synthase ◽  
Palmer Amaranth ◽  
Effective Control ◽  
Herbicide Resistant ◽  
First Case ◽  
Whole Plant ◽  
Chlorimuron Ethyl ◽  
Als Inhibitors ◽  
Als Inhibitor

Abstract Palmer amaranth is the latest pigweed species documented in Connecticut; it was identified there in 2019. In a single-dose experiment, the Connecticut Palmer amaranth biotype survived the field-use rates of glyphosate (840 g ae ha−1) and imazaquin (137 g ai ha−1) herbicides applied separately. Additional experiments were conducted to (1) determine the level of resistance to glyphosate and acetolactate synthase (ALS) inhibitors in the Connecticut-resistant (CT-Res) biotype using whole-plant dose-response bioassays, and (2) evaluate the response of the CT-Res biotype to POST herbicides commonly used in Connecticut cropping systems. Based on the effective dose required for 90% control (ED90), the CT-Res biotype was 10-fold resistant to glyphosate when compared with the Kansas-susceptible (KS-Sus) biotype. Furthermore, the CT-Res biotype was highly resistant to ALS-inhibitor herbicides; only 18% control was achieved with 2,196 g ai ha−1 imazaquin. The CT-Res biotype was also cross-resistant to other ALS-inhibitor herbicides, including chlorimuron-ethyl (13.1 g ai ha−1), halosulfuron-methyl (70 g ai ha−1), and sulfometuron-methyl (392 g ai ha−1). The CT-Res Palmer amaranth was controlled 75% to 100% at 21 d after treatment (DAT) with POST applications of 2,4-D (386 g ae ha−1), carfentrazone-ethyl (34 g ai ha−1), clopyralid (280 g ae ha−1), dicamba (280 g ae ha−1), glufosinate (595 g ai ha−1), lactofen (220 g ai ha−1), oxyfluorfen (1,121g ai ha−1), and mesotrione (105 g ai ha−1) herbicides. Atrazine (2,240 g ai ha−1) controlled the CT-Res biotype only 52%, suggesting the biotype is resistant to this herbicide as well. Here we report the first case of Palmer amaranth from Connecticut with multiple resistance to glyphosate and ALS inhibitors. Growers should proactively use all available weed control tactics, including the use of effective PRE and alternative POST herbicides (tested in this study), for effective control of the CT-Res biotype.

Molecular Basis of Resistance to ALS-Inhibitor Herbicides in Greater Beggarticks

Weed Science ◽  
2009 ◽  
Vol 57 (5) ◽  
pp. 474-481 ◽  
Author(s):  
Fabiane P. Lamego ◽  
Dirk Charlson ◽  
Carla A. Delatorre ◽  
Nilda R. Burgos ◽  
Ribas A. Vidal
Keyword(s):  
Amino Acid ◽  
Molecular Basis ◽  
Single Point ◽  
Acetolactate Synthase ◽  
Amino Acid Sequences ◽  
Single Point Mutation ◽  
Weed Species ◽  
Herbicide Resistant ◽  
Als Inhibitors ◽  
Als Inhibitor

Soybean is a major crop cultivated in Brazil, and acetolactate synthase (ALS)-inhibiting herbicides are widely used to control weeds in this crop. The continuous use of these ALS-inhibiting herbicides has led to the evolution of herbicide-resistant weeds worldwide. Greater beggarticks is a polyploid species and one of the most troublesome weeds in soybean production since the discovery of ALS-resistant biotypes in 1996. To confirm and characterize the resistance of greater beggarticks to ALS inhibitors, whole-plant bioassays and enzyme experiments were conducted. To investigate the molecular basis of resistance in greater beggarticks theALSgene was sequenced and compared between susceptible and resistant biotypes. Our results confirmed that greater beggarticks is resistant to ALS inhibitors and also indicated it possesses at least three isoforms of theALSgene. Analysis of the nucleotide and deduced amino acid sequences among the isoforms and between the biotypes indicated that a single point mutation, G–T, in oneALSisoform from the resistant biotype resulted in an amino acid substitution, Trp574Leu. Two additional substitutions were observed, Phe116Leu and Phe149Ser, in a second isoform of the resistant biotype, which were not yet reported in any other herbicide-resistantALSgene; thus, their role in conferring herbicide resistance is not yet ascertained. This is the first report ofALSmutations in an important, herbicide-resistant weed species from Brazil.

scholarly journals Administrative Professionals in New Zealand: Their Professional Development Opportunities and Career Pathways

2021 ◽  
Author(s):  
◽  
Ethelwyn Eva Lloyd
Keyword(s):  
Professional Development ◽  
New Zealand ◽  
Focus Groups ◽  
Ad Hoc ◽  
Career Pathways ◽  
Business World ◽  
The North ◽  
On Line ◽  
Administrative Professionals ◽  
North And South

<p>This descriptive study to investigate the perceptions of administrative professionals of their professional development opportunities and career pathways was conducted mid-2009. The study used an on-line survey and focus groups. One hundred and ninety-three responded to the survey from throughout New Zealand. Fifteen of those respondents participated in the focus groups, held in both the North and South Islands. The majority of participants were from larger organisations who perceived that training and professional development was available for them and supported. However, the professional development available was often ad hoc, with no specific goal. Many participants perceive themselves as undervalued within the business world and noted that even where support for professional development was available there were significant barriers. These barriers, impacting on the availability and the uptake of professional development opportunities and career pathways, were both internal (value of self) and external. A conceptual framework is presented of the relationship between the key elements from the research, value of self and value of the role, and the impacts of those on professional development opportunities and career pathways.</p>

scholarly journals Administrative Professionals in New Zealand: Their Professional Development Opportunities and Career Pathways

2021 ◽  
Author(s):  
◽  
Ethelwyn Eva Lloyd
Keyword(s):  
Professional Development ◽  
New Zealand ◽  
Focus Groups ◽  
Ad Hoc ◽  
Career Pathways ◽  
Business World ◽  
The North ◽  
On Line ◽  
Administrative Professionals ◽  
North And South

<p>This descriptive study to investigate the perceptions of administrative professionals of their professional development opportunities and career pathways was conducted mid-2009. The study used an on-line survey and focus groups. One hundred and ninety-three responded to the survey from throughout New Zealand. Fifteen of those respondents participated in the focus groups, held in both the North and South Islands. The majority of participants were from larger organisations who perceived that training and professional development was available for them and supported. However, the professional development available was often ad hoc, with no specific goal. Many participants perceive themselves as undervalued within the business world and noted that even where support for professional development was available there were significant barriers. These barriers, impacting on the availability and the uptake of professional development opportunities and career pathways, were both internal (value of self) and external. A conceptual framework is presented of the relationship between the key elements from the research, value of self and value of the role, and the impacts of those on professional development opportunities and career pathways.</p>

Studies of Ptiliidae (Coleoptera) in the Spirit Collection of the Natural History Museum, London 2: New species and records from P. Hammond's visit to New Zealand in 1983–84

2018 ◽  
Vol 154 (3) ◽  
pp. 179-196
Author(s):  
Michael Darby
Keyword(s):  
New Species ◽  
New Zealand ◽  
Natural History ◽  
Natural History Museum ◽  
History Museum ◽  
The North ◽  
Three New Species ◽  
North And South

Some 2,000 Ptiliidae collected in the North and South Islands of New Zealand in 1983/1984 by Peter Hammond of the Natural History Museum, London, are determined to 34 species, four of which are new to the country. As there are very few previous records, most from the Auckland district of North Island, the Hammond collection provides much new distributional data. The three new species: Nellosana insperatus sp. n., Notoptenidium flavum sp. n., and Notoptenidium johnsoni sp. n., are described and figured; the genus Ptiliodes is moved from Acrotrichinae to Ptiliinae, and Ptenidium formicetorum Kraatz recorded as a new introduction. Information is provided to aid separation of the new species from those previously recorded.

Investigating the resistance levels and mechanisms to penoxsulam and cyhalofop-butyl in barnyardgrass (Echinochloa crus-galli) from Ningxia province, China

Weed Science ◽  
2021 ◽  
pp. 1-25
Author(s):  
Qian Yang ◽  
Xia Yang ◽  
Zichang Zhang ◽  
Jieping Wang ◽  
Weiguo Fu ◽  
...  
Keyword(s):  
Herbicide Resistance ◽  
Molecular Mechanisms ◽  
Acetolactate Synthase ◽  
Rice Fields ◽  
Target Site ◽  
Herbicide Resistant ◽  
Susceptible Populations ◽  
High Level ◽  
Als Inhibitor ◽  
Encoding Genes

Abstract Barnyardgrass (Echinochloa crus-galli) is a noxious grass weed which infests rice fields and causes huge crop yield losses. In this study, we collected twelve E. crus-galli populations from rice fields of Ningxia province in China and investigated the resistance levels to acetolactate synthase (ALS) inhibitor penoxsulam and acetyl-CoA carboxylase (ACCase) inhibitor cyhalofop-butyl. The results showed that eight populations exhibited resistance to penoxsulam and four populations evolved resistance to cyhalofop-butyl. Moreover, all of the four cyhalofop-butyl-resistant populations (NX3, NX4, NX6 and NX7) displayed multiple-herbicide-resistance (MHR) to both penoxsulam and cyhalofop-butyl. The alternative herbicides bispyribac-sodium, metamifop and fenoxaprop-P-ethyl cannot effectively control the MHR plants. To characterize the molecular mechanisms of resistance, we amplified and sequenced the target-site encoding genes in resistant and susceptible populations. Partial sequences of three ALS genes and six ACCase genes were examined. A Trp-574-Leu mutation was detected in EcALS1 and EcALS3 in two high-level (65.84- and 59.30-fold) penoxsulam-resistant populations NX2 and NX10, respectively. In addition, one copy (EcACC4) of ACCase genes encodes a truncated aberrant protein due to a frameshift mutation in E. crus-galli populations. None of amino acid substitutions that are known to confer herbicide resistance were detected in ALS and ACCase genes of MHR populations. Our study reveals the widespread of multiple-herbicide resistant E. crus-galli populations at Ningxia province of China that exhibit resistance to several ALS and ACCase inhibitors. Non-target-site based mechanisms are likely to be involved in E. crus-galli resistance to the herbicides, at least in four MHR populations.

Controlling Herbicide-Resistant Annual Bluegrass (Poa annua) Phenotypes with Methiozolin

2017 ◽  
Vol 31 (3) ◽  
pp. 470-476 ◽  
Author(s):  
James T. Brosnan ◽  
Jose J. Vargas ◽  
Gregory K. Breeden ◽  
Sarah L. Boggess ◽  
Margaret A. Staton ◽  
...  
Keyword(s):  
Acetolactate Synthase ◽  
Target Site ◽  
Multiple Resistance ◽  
Herbicide Resistant ◽  
Annual Bluegrass ◽  
Microtubule Inhibitors ◽  
Effective Option ◽  
Target Site Resistance ◽  
Susceptible Control ◽  
Als Inhibitors

Methiozolin is an isoxazoline herbicide being investigated for selective POST annual bluegrass control in managed turfgrass. Research was conducted to evaluate methiozolin efficacy for controlling two annual bluegrass phenotypes with target-site resistance to photosystem II (PSII) or enolpyruvylshikimate-3-phosphate synthase (EPSPS)-inhibiting herbicides (i.e., glyphosate), as well as phenotypes with multiple resistance to microtubule and EPSPS or PSII and acetolactate synthase (ALS)-inhibiting herbicides. All resistant phenotypes were established in glasshouse culture along with a known herbicide-susceptible control and treated with methiozolin at 0, 125, 250, 500, 1000, 2000, 4000, or 8000 g ai ha−1. Methiozolin effectively controlled annual bluegrass with target-site resistance to inhibitors of EPSPS, PSII, as well as multiple resistance to EPSPS and microtubule inhibitors. Methiozolin rates required to reduce aboveground biomass of these resistant phenotypes 50% (GR50 values) were not significantly different from the susceptible control, ranging from 159 to 421 g ha−1. A phenotype with target-site resistance to PSII and ALS inhibitors was less sensitive to methiozolin (GR50=862 g ha−1) than a susceptible phenotype (GR50=423 g ha−1). Our findings indicate that methiozolin is an effective option for controlling select annual bluegrass phenotypes with target-site resistance to several herbicides.

scholarly journals Occurrence of multiple sclerosis in the north and south of New Zealand.

1987 ◽  
Vol 50 (2) ◽  
pp. 134-139 ◽  
Author(s):  
D C Skegg ◽  
P A Corwin ◽  
R S Craven ◽  
J A Malloch ◽  
M Pollock
Keyword(s):  
Multiple Sclerosis ◽  
New Zealand ◽  
The North ◽  
North And South

In vitro and whole-plant magnitude and cross-resistance characterization of two imidazolinone-resistant sugarbeet (Beta vulgaris) somatic cell selections

Weed Science ◽  
1998 ◽  
Vol 46 (1) ◽  
pp. 24-29 ◽  
Author(s):  
Terry R. Wright ◽  
Donald Penner
Keyword(s):  
Somatic Cell ◽  
Shoot Culture ◽  
Acetolactate Synthase ◽  
Cross Resistance ◽  
Shoot Cultures ◽  
Als Inhibitors ◽  
Whole Plants ◽  
Inhibitor Resistance ◽  
Als Inhibitor

Acetolactate synthase (ALS)-inhibiting herbicide carryover in soil can severely affect sugarbeets grown in the year(s) following application. Two newly developed imidazolinone-resistant (IMI-R) sugarbeet somatic cell selections (Sir-13 and 93R30B) were examined for magnitude of resistance and extent of cross-resistance to other classes of ALS inhibitors and compared to a previously developed sulfonylurea-resistant (SU-R) selection, Sur. In vitro shoot culture tests indicated Sir-13 resistance was specific to imidazolinone (IMI) herbicides at approximately a 100-fold resistance compared to the sensitive control sugarbeet. Sur was 10,000-fold resistant to the sulfonylurea (SU) herbicide, chlorsulfuron, and 40-fold resistant to the triazolopyrimidine sulfonanilide (TP) herbicide, flumetsulam, but not cross-resistant to the IMI herbicides. 93R30B was selected for IMI-R from a plant homozygous for the SU-R allele,Sur, and displayed similar in vitro SU-R and TP-R as Sur, but also displayed a very high resistance to various IMI herbicides (400- to 3,600-fold). Compared to the sensitive control, Sir-13 was 300- and > 250-fold more resistant to imazethapyr and imazamox residues in soil, respectively. Response by whole plants to postemergence herbicide applications was similar to that observed in shoot cultures. Sir-13 exhibited > 100-fold resistance to imazethapyr as well as imazamox, and 93R30B showed > 250-fold resistance to both herbicides. 93R30B showed great enough resistance to imazamox to merit consideration of imazamox for use as a herbicide in these sugarbeets. Sir-13 showed a two- to threefold higher level of resistance in the homozygous vs. heterozygous state, indicating that like most ALS-inhibitor resistance traits, it was semidominantly inherited.

Sign in / Sign up

Export Citation Format

Share Document