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Stephen B. Powles - One of the best experts on this subject based on the ideXlab platform.

  • cytochrome p450 cyp81a10v7 in lolium rigidum confers metabolic resistance to Herbicides across at least five modes of action
    Plant Journal, 2021
    Co-Authors: Heping Han, Roland Beffa, Susana Gonzalez, Frank Maiwald, Jing Wang, Stephen B. Powles
    Abstract:

    Rapid and widespread evolution of multiple herbicide resistance in global weed species endowed by increased capacity to metabolize (degrade) Herbicides (metabolic resistance) is a great threat to herbicide sustainability and global food production. Metabolic resistance in the economically damaging crop weed species Lolium rigidum is well known but a molecular understanding has been lacking. We purified a metabolic resistant (R) subset from a field evolved R L. rigidum population. The R, the herbicide susceptible (S) and derived F2 populations were used for candidate herbicide resistance gene discovery by RNA sequencing. A P450 gene CYP81A10v7 was identified with higher expression in R vs. S plants. Transgenic rice overexpressing this Lolium CYP81A10v7 gene became highly resistant to acetyl-coenzyme A carboxylase- and acetolactate synthase-inhibiting Herbicides (diclofop-methyl, tralkoxydim, chlorsulfuron) and moderately resistant to hydroxyphenylpyruvate dioxygenase-inhibiting herbicide (mesotrione), photosystem II-inhibiting Herbicides (atrazine and chlorotoluron) and the tubulin-inhibiting herbicide trifluralin. This wide cross-resistance profile to many dissimilar Herbicides in CYP81A10v7 transgenic rice generally reflects what is evident in the R L. rigidum. This report clearly showed that a single P450 gene in a cross-pollinated weed species L. rigidum confers resistance to Herbicides of at least five modes of action across seven herbicide chemistries.

  • distribution and frequency of herbicide resistant wild oat avena spp across the western australian grain belt
    Crop & Pasture Science, 2009
    Co-Authors: Mechelle J Owen, Stephen B. Powles
    Abstract:

    In 2005, a random survey was conducted across 14 million hectares of the Western Australian grain belt to establish the frequency and distribution of herbicide-resistant wild oat (Avena spp.) in cropping fields. In total, 677 cropping fields were visited, with wild oat populations collected from 150 fields. These wild oat populations were screened with several Herbicides commonly used to control this weed. Most of the wild oat populations (71%) were found to contain individuals resistant to the ACCase-inhibiting herbicide diclofop-methyl. Resistance to other ACCase-inhibiting Herbicides was markedly lower. Herbicides of alternative modes of action were effective on all wild oat populations. Overall, wild oat resistance to diclofop-methyl was found to be widespread across the Western Australian grain belt, but resistance to other Herbicides was relatively low. Therefore, through diversity in herbicide use and with cultural management, it is possible to maintain wild oat populations at a low level and/or minimise herbicide resistance evolution.

  • multiple herbicide resistance across four modes of action in wild radish raphanus raphanistrum
    Weed Science, 2004
    Co-Authors: Michael J Walsh, Stephen B. Powles, Brett R Beard, Ben T Parkin, Sally A Porter
    Abstract:

    Abstract Populations of wild radish were collected from two fields in the northern Western Australian wheatbelt, where typical herbicide-use patterns had been practiced for the previous 17 seasons within an intensive crop production program. The herbicide resistance status of these populations clearly established that there was multiple-herbicide resistance across many Herbicides from at least four modes of action. One population exhibited multiple-herbicide resistance to the phytoene desaturase (PDS)–inhibiting herbicide diflufenican (3.0-fold), the auxin analog herbicide 2,4-D (2.2-fold), and the photosystem II–inhibiting Herbicides metribuzin and atrazine. Another population was found to be multiply resistant to the acetolactate synthase–inhibiting Herbicides, the PDS-inhibiting herbicide diflufenican (2.5-fold), and the auxin analog herbicide 2,4-D amine (2.4-fold). Therefore, each population has developed multiple-herbicide resistance across several modes of action. The multiple resistance status of ...

  • evolution of herbicide resistance in weeds initial frequency of target site based resistance to acetolactate synthase inhibiting Herbicides in lolium rigidum
    Heredity, 2002
    Co-Authors: C. Preston, Stephen B. Powles
    Abstract:

    The frequency of individuals resistant to two acetolactate synthase (ALS)-inhibiting Herbicides in three previously untreated populations of Lolium rigidum was determined. The frequency of individuals resistant to the sulfonylurea herbicide sulfometuron-methyl varied from 2.2 × 10−5 to 1.2 × 10−4 and the frequency of individuals resistant to the imidazolinone herbicide imazapyr varied from 1 × 10−5 to 5.8 × 10−5 depending on the population. Application of sulfometuron-methyl selected individuals with a herbicide-insensitive ALS, which was also cross-resistant to imazapyr. The high initial frequency of individuals resistant to ALS-inhibiting Herbicides in L. rigidumpopulations never previously exposed to these Herbicides helps explain the rapid evolution of herbicide resistance in this species once ALS-inhibiting Herbicides were used.

  • multiple herbicide resistance in annual ryegrass lolium rigidum a driving force for the adoption of integrated weed management
    1992
    Co-Authors: Stephen B. Powles, John M Matthews
    Abstract:

    Ryegrass (Lolium rigidum) is an abundant, polymorphic, wind-pollinated, self-incompatible annual grass that is ubiquitous in cropping regions of southern Australia. Over the past decade hundreds of herbicide resistant rye grass populations have appeared in response to selection pressure from Herbicides. A striking feature of resistance in ryegrass is the development of multiple herbicide resistance. Currently there are biotypes of ryegrass that are resistant to Herbicides within ten different chemical classes. There are varying patterns of resistance between different biotypes. Ryegrass populations that have developed resistance to one herbicide can rapidly develop resistance to new Herbicides that are effective initially. Genetic diversity in ryegrass and the frequent exposure of huge numbers of plants to herbicide results in the selection of one to many different resistance genes.

John Broster - One of the best experts on this subject based on the ideXlab platform.

  • herbicide resistance levels in annual ryegrass lolium rigidum gaud and wild oat avena spp in southwestern new south wales
    Plant protection quarterly, 2013
    Co-Authors: John Broster, Eric Koetz
    Abstract:

    In 2010, a random survey was conducted across the cereal cropping zone of southwestern New South Wales to determine the level of herbicide resistance in annual ryegrass (Lolium rigidum Gaud.) and wild oat (Avena spp.) populations. In total, 192 paddocks were visited resulting in 124 annual ryegrass and 104 wild oat seed samples collected for testing. These samples were then screened to the herbicide groups commonly used for annual ryegrass (ACCase, ALS, triazine, dinitroaniline and glycine) and wild oat (ACCase, ALS, thiocarbamate and glycine) control in Australia. The majority of ryegrass samples were resistant to aryloxyphenoxypropionate (56%) and sulfonylurea (53%) Herbicides. High levels of resistance were also found for cyclohexanedione (32%) and imidazolinone (38%) Herbicides. This represents an increase compared to the 10-14% detected in a 1991 survey. Resistance was found only within ACCase Herbicides in the wild oat; 37% were resistant to a aryloxyphenoxypropionate herbicide and 14% were resistant to a cyclohexanedione herbicide. Thirty four percent of the 110 ryegrass samples tested to five herbicide groups (aryloxyphenoxypropionate, cyclohexanedione, ALS, triazine and dinitroaniline) were resistant to two or more herbicide groups, while multiple resistance was only detected in 8% of wild oat samples tested to four herbicide groups (aryloxyphenoxypropionate, cyclohexanedione, ALS and thiocarbamate). Thirty percent of ryegrass and 62% of wild oat samples were susceptible to all Herbicides. Resistance levels for both ryegrass and wild oat in this survey were lower than reported for a 2007 survey to the immediate east of this survey. The levels of resistance found for many Herbicides, while lower than the adjoining survey, are still significant and highlight the importance of adopting an integrated approach to weed management. This integrated approach is necessary for minimising resistance to commonly used Herbicides, and extending their commercial life.

  • a decade of monitoring herbicide resistance in lolium rigidum in australia
    Animal Production Science, 2006
    Co-Authors: John Broster, James Pratley
    Abstract:

    Charles Sturt University commenced herbicide resistance monitoring in 1991. A random survey in 1991 to determine the level of resistance in annual ryegrass (Lolium rigidum) to selective Herbicides across the south-west slopes region of New South Wales found that 30% of samples were resistant to at least 1 herbicide. A subsequent survey of commercially available ryegrass seed found that 58% of these samples were resistant to at least 1 herbicide. As a result of these findings, a commercial testing service was established and has since received samples from a large proportion of the southern Australian cropping belt. Seventy-seven percent of samples tested were resistant to Group AI, 40% to Group B and 22% to Group AII Herbicides. Lower levels of resistance were found to Group D (8%), Group C (1%) and Group M (0.4%) Herbicides. The correlation between resistance in Group AI and AII Herbicides was lower than expected given that these Herbicides are considered to have the same mode of action. Within the Group AI Herbicides the observed response of the samples was consistent across herbicide formulations. Resistance to clethodim varied from observed responses to other Group AII Herbicides. The variation in resistance levels (and degree of multiple resistance) in each Australian state is discussed in relation to environmental conditions and cultural practices. The size of this dataset allows for the analysis of the relationships present among herbicide resistant annual ryegrass.

Monquero, Patricia Andrea - One of the best experts on this subject based on the ideXlab platform.

  • SENSIBILIDADE DE MUDAS PRÉ-BROTADAS E MINIRREBOLOS DE CANA-DE-AÇÚCAR A HERBICIDAS PRÉ-EMERGENTES
    'Composicao Revista de Ciencias Sociais da Universidade Federal de Mato Grosso do Sul', 2020
    Co-Authors: Paulo Vinicius Da ,silva, Monquero, Patricia Andrea, Dias, Roque De Carvalho, Viana, Henrique Rodrigues Milagres, Malardo, Marcelo Rafael, Inácio, Estela Maris, Ribeiro, Nagila Moraes, Christoffoleti, Pedro Jacob
    Abstract:

    A cana-de-açúcar, cultivada através de minirrebolos e mudas pré-brotadas, podem apresentar maior sensibilidade a herbicidas em comparação ao convencional. Objetivou-se avaliar a seletividade inicial de tratamentos herbicidas aplicados em pré-emergência em variedades de cana-de-açúcar cultivadas nos sistemas de mudas pré-brotadas e de minirrebolos. Em casa de vegetação foram realizados dois experimentos, um com MPBs (RB966928 e IAC 5000) e outro com minirrebolos (RB92579 e RB966928). O delineamento foi inteiramente casualizado, com quatro repetições em esquema fatorial 8 x 5, sendo oito tratamentos (amicarbazone (980,0 g ha-1); metribuzin (921,6 g ha-1); indaziflam (50,0 g ha-1); isoxaflutole (78,8 g ha-1); amicarbazone + indaziflam (703,5 + 37,5 g ha-1); metribuzin + indaziflam (460,8 + 37,5 g ha-1), isoxaflutole + indaziflam (56,3 + 37,5 g ha-1) e  testemunha (sem herbicidas) e cinco épocas de avaliação (7, 14, 21 28 e 35 dias após aplicação dos tratamentos e emergência,  para MPBs e minirrebolos, respectivamente). Em MPBs, os herbicidas amicarbazone e metribuzin, resultaram em 0,00% de fitotoxicidade nas duas variedades. Nos minirrebolos, o isoxaflutole isolado e associado com indaziflam resultaram em alta fitotoxicidade independentemente da variedade. Logo o sistema de plantio e as variedades, influenciam na seletividade de herbicidas na cultura da cana-de-açúcar.Palavras-chave: cana-planta; fitotoxicidade; aplicação; sistemas de plantio. SENSITIVITY OF PRE-BUDDED SEEDLINGS AND SUGAR CANE MULTIBUD SETTS TO PRE-EMERGENT Herbicides ABSTRACT: The sugarcane, grown through pre-budded seedlings and multibud setts, may have more sensitive to Herbicides compared to conventional. The objective of this study was to evaluate the initial selectivity of pre-emergent herbicide treatment in sugarcane varieties cultivated in the pre-budded seedlings and multibud setts systems. Two experiments were carried out in the greenhouse, one with MPBs (RB966928 and IAC 5000) and the other with multibud setts (RB92579 and RB966928).The design was completely randomized, with four replications in an 8 x 5 factorial scheme, with eight treatments: amicarbazone (1400 g ha-1); metribuzin (1920 g ha-1); indaziflam (100 g ha-1); isoxaflutole (105 g ha-1); amicarbazone + indaziflam (1005 +75 g ha-1); metribuzin + indaziflam (960 + 75 g ha-1), isoxaflutole + indaziflam (75 + 75 g ha-1) and control (without Herbicides) and five evaluation periods (7, 14, 21, 28 and 35 days after application of the DAT and emergency treatments, for MPBs and multibud setts, respectively). In MPBs, the Herbicides amicarbazone and metribuzin, resulted in 0.00% phytotoxicity in both varieties. In multibud setts, isoxaflutole alone and associated with indaziflam resulted in high phytotoxicity regardless of variety. Soon the planting system and the varieties, influence the selectivity of Herbicides in the culture of sugarcane.Keywords: sugarcane-plant; phytotoxicity; application; planting systems

  • EFEITO DE HERBICIDAS NO CRESCIMENTO INICIAL DO SORGO SACARINO
    'Composicao Revista de Ciencias Sociais da Universidade Federal de Mato Grosso do Sul', 2019
    Co-Authors: Furquim, Lucas Tadeu, Monquero, Patricia Andrea, Silva, Rafael Pires
    Abstract:

    A presença de plantas daninhas pode reduzir severamente o rendimento do sorgo sacarino (Sorghum bicolor), e em função do reduzido número de herbicidas registrados, o objetivo do trabalho foi avaliar o efeito de herbicidas no crescimento inicial dessa cultura. O delineamento experimental foi inteiramente casualizado com cinco repetições, sendo o haloxyfop-methyl, cyhalofop-butil, fomesafem, imazaquim, lactofen, atrazine, 2,4-D e saflufenacil aplicados em diferentes doses em pós-emergência inicial da cultura e os herbicidas atrazine, atrazine+simazine, hexazinone e s-metolachlor em pré-emergência da cultura. As avaliações de fitointoxicação foram realizadas aos 7, 14, 21 e 30 dias após a aplicação (DAT) e a biomassa seca da parte aérea avaliada aos 30 DAT. Em pós-emergência, os herbicidas haloxyfop-methyl e imazaquim provocaram alta fitointoxicação e impactos na biomassa das plantas. 2,4-D e atrazine não provocaram diferenças significativas com relação à testemunha tanto em fitointoxicação como na biomassa. O herbicida lactofen provocou baixa fitointoxicação, todavia, saflufenacil e fomesafen promoveram fitointoxicação na dose comercial próximo a 40% e alterações na biomassa. Dos herbicidas utilizados em pré-emergência, apenas hexazinone e s-metolachlor demonstraram fitointoxicação e alterações na biomassa. Conclui-se que os herbicidas atrazine, lactofen e 2,4-D podem ser utilizados em aplicações em pós-emergência, e atrazine e atrazine+simazine em pré-emergência.Palavras-chave: fitointoxicação, Sorghum bicolor, pré-emergente, pós-emergente. EFFECT OF Herbicides ON THE INITIAL GROWTH OF SWEET SORGHUM  ABSTRACT: The presence of weeds may severely reduce yield of sweet sorghum (Sorghum bicolor), and due to the reduced number of Herbicides registered, the objective of this work was to evaluate the effect of Herbicides on the initial growth of this crop. The experimental design was completely randomized with five replicate, being, the Herbicides haloxyfop-methyl, cyhalofop-butyl, fomesafem, imazaquim, lactofen, atrazine, 2,4-D and saflufenacil were applied at different initial post-emergence rates and Herbicides atrazine, atrazine + simazine, hexazinone and s- metolachlor in pre-emergence of the culture. The phytointoxication evaluations were performed at 7, 14, 21 and 30 days after application (DAT) and the dry biomass of the aerial part evaluated at 30 DAT. In post-emergence, the Herbicides haloxyfop-methyl and imazaquim caused high phytointoxication and impacts on plant biomass. 2,4-D and atrazine did not cause significant differences in relation to the control in both phytointoxication and biomass. The herbicide lactofen caused low phytointoxication, however, saflufenacil and fomesafen promoted phytointoxication at commercial dose close to 40% and changes in biomass. Of the Herbicides used in pre-emergence, only hexazinone and s-metolachlor demonstrated phytointoxication and changes in biomass. It is concluded that the Herbicides atrazine, lactofen and 2,4-D can be used in post-emergence applications, and pre-emergence atrazine and atrazine + simazine.Keywords: phytointoxication, Sorghum bicolor, pre-emergent, post-emergent

  • Crescimento inicial de mudas pré brotadas de cana-de-açúcar submetidas a aplicação de herbicidas
    'Revista Brasileira de Herbicidas', 2017
    Co-Authors: Sabbag, Renan Dos Santos, Monquero, Patricia Andrea, Hirata, Andreia Cristina Silva, Santos, Paulo Henrique Vieira Dos
    Abstract:

    The chemical weed control is the most used in sugarcane culture, and studies covering the effects of these Herbicides on the development of pre-sprouted seedlings of sugarcane. The objective of this work was to evaluate the effect of the Herbicides ametryn, clomazone, hexazinone + diuron, metribuzin, sulfentrazone and tebuthiuron isolated and in association with saflufenacil in the initial growth of pre-sprouted seedlings of sugarcane varieties at different times of application. The experiment was conducted in a greenhouse in a completely randomized design, in a 14 x 2 factorial scheme, 14 herbicide treatments and 2 application times after planting (3 and 10 DAP), with four replications. The Herbicides, at their recommended doses, were applied 3 or 10 days after seedling transplant of the varieties: RB 86 7515, RB 85 5156, RB 96 6928 and RB 97 5201. The percentage of phytotoxicity was evaluated at 7, 15, 30 and 60 days after application of the treatments (DAT). The height of the plants, leaf area and dry shoot biomass were evaluated at 60 DAT. The Herbicides caused a differential impact according to the varieties and the time of application, however, in the last evaluation, there was low phytotoxicity in most evaluations. For RB 867515 herbicide application at both 3 and 10 DAP was safe, for RB 966928 and RB 975201 the application at 3 DAP caused less phytotoxicity, whereas for RB 855156 it was at 10 DAP. It is concluded that the varieties differ in phytotoxicity to the evaluated Herbicides, being RB 867515 the most tolerant and the association saflufenacil + clomazone and clomazone caused greater initial phytotoxicity in the varieties and in the time studied.O método químico de controle de plantas daninhas é o mais utilizado na cultura da cana-de-açúcar, sendo necessários estudos que englobem o efeito destes herbicidas sobre o desenvolvimento de mudas pré-brotadas de cana de açúcar (MPB). O objetivo deste trabalho foi avaliar o efeito da aplicação dos herbicidas ametryn, clomazone, hexazinone + diuron, metribuzin, sulfentrazone e tebuthiuron, isolados e em associação com saflufenacil, no crescimento inicial de mudas pré-brotadas de variedades de cana-de-açúcar. O ensaio foi conduzido em casa de vegetação em delineamento experimental inteiramente casualizado, em esquema fatorial 14 x 2, sendo 14 tratamentos herbicidas e 2 épocas de aplicação após o plantio (3 e 10 DAP), com quatro repetições. Os herbicidas, em suas doses recomendadas, foram aplicados aos 3 ou 10 dias após o transplante das mudas (DAP) das variedades: RB 86 7515, RB 85 5156, RB 96 6928 e RB 97 5201. A porcentagem de fitotoxicidade foi avaliada aos 7, 15, 30 e 60 dias após a aplicação dos tratamentos (DAT). A estatura das plantas, área foliar e biomassa seca da parte aérea foram avaliadas aos 60 DAT. Os herbicidas causaram impacto diferenciado em função das variedades e época de aplicação, todavia, na última avaliação, houve baixa fitotoxicidade na maioria das avaliações. Para a RB 867515 a aplicação dos herbicidas tanto aos 3 como aos 10 DAP foi segura, já para as variedades RB 966928 e RB 975201 a aplicação aos 3 DAP causou menor fitotoxicidade, enquanto, para a RB 855156 foi aos 10 DAP. Conclui-se que as variedades diferem quanto à fitotoxicidade aos herbicidas avaliados, sendo a RB 867515 a mais tolerante e a associação saflufenacil + clomazone e clomazone provocaram maior fitotoxicidade, dentre os tratamentos, nas variedades e épocas estudadas

  • Seletividade de herbicidas em espécies de gramas ornamentais
    'Revista Brasileira de Herbicidas', 2012
    Co-Authors: Monquero, Patricia Andrea, Filho, José Miguel, Gutierrez, Aline Baldini, Barbosa, Lincon Nunes
    Abstract:

    The experiment was conducted with the objective of evaluating the selectivity of Herbicides, applied in different times, in ornamental turf grasses. The first experiment was conducted in greenhouse conditions in randomized entirely design, with four replications, in a 4 x 5 x 2 factorial scheme. The factors corresponded to the pre-planting application Herbicides ( sulfentrazone - 800 g ha-1, s-metolachlor - 1440 g ha-1 and atrazine - 2000 g ha-1 and  control without herbicide application) in five species of turfgrass: Zoysia japonica (emerald), Axonopus compressus (blanket grass), Paspalum notatum (bahia grass), Zoysia tenuifolia (no-mow grass), Stenotaphrum secundatum (sant agostine grass), in sandy loam and clayey texture soils. In the second experiment, the experimental design was completely randomized, with four replications in a 6 x 6 factorial scheme. The factors corresponded to the five post emergence Herbicides: atrazine (2000 g ha-1), sulfentrazone (800 g ha-1), halosulfuron (112.5 g ha-1), bentazon (0.72 g ha-1) and 2.4 D (670 g ha-1) applied on the five grasses, cited above and control without herbicide application. Phytotoxicity evaluations were assessed at at 7, 14, 21, 28 and 35 days after herbicide application. In the case of pre planting Herbicides, were not detected any phytotoxicity in the grass species, regardless of soil texture. In the experiment with post-emergent Herbicides, the bahia and blanket grass were sensitive to the herbicide atrazine, with 38 and 33% phytotoxicity at 21 DAA. However, the recovery of bahia grass was more effective at 35 DAA. The sulfentrazone was phytotoxic on blanket grass. The Herbicides bentazon, 2,4-D and halosulfuron were selective to all species studied.O objetivo desse trabalho foi verificar a seletividade de herbicidas, aplicados em diferentes épocas, em espécies de gramas ornamentais. O primeiro experimento foi conduzido em delineamento inteiramente casualizado, com quatro repetições, em esquema fatorial 4 x 5 x 2. Os fatores corresponderam à aplicação dos herbicidas em pré-plantio (sulfentrazone - 800 g ha-1, s-metolachlor - 1440 g ha-1, atrazina - 2000 g ha-1, além de testemunha sem aplicação de herbicida) em cinco espécies de gramas: Zoysia japonica (esmeralda), Axonopus compressus (são carlos), Paspalum notatum (batatais), Zoysia tenuifolia (japonesa), Stenotaphrum secundatum (santo agostinho) em dois tipos de solo quanto a textura (argilosa e média), além das testemunhas, sem aplicação de herbicida. No segundo experimento, o delineamento foi inteiramente casualizado, com quatro repetições, em esquema fatorial 6 x 5, sendo cinco herbicidas: atrazina (2000 g ha-1), sulfentrazone (800 g ha-1), halosulfuron (112,5 g ha-1), bentazon (0,72 g ha-1) e 2,4-D (670 g ha-1), aplicados sobre as cinco gramíneas citadas e testemunhas sem aplicação de herbicida. As avaliações visuais foram feitas aos 7, 14, 21, 28 e 35 dias após a aplicação dos herbicidas. Todos os herbicidas aplicados em pré-plantio foram seletivos para as espécies estudadas, independente da textura do solo. No experimento com pós-emergentes, as gramas são carlos e batatais foram sensíveis a atrazina, com 38 e 33% de fitotoxicidade aos 21 DAA. Entretanto, a recuperação da grama batatais foi mais efetiva aos 35 DAA. O herbicida sulfentrazone provocou fitotoxicidade apenas na grama são carlos. Os herbicidas bentazon, 2,4-D e halosulfurom aplicados sobre as plantas foram seletivos para todas as espécies estudadas

James Pratley - One of the best experts on this subject based on the ideXlab platform.

  • a decade of monitoring herbicide resistance in lolium rigidum in australia
    Animal Production Science, 2006
    Co-Authors: John Broster, James Pratley
    Abstract:

    Charles Sturt University commenced herbicide resistance monitoring in 1991. A random survey in 1991 to determine the level of resistance in annual ryegrass (Lolium rigidum) to selective Herbicides across the south-west slopes region of New South Wales found that 30% of samples were resistant to at least 1 herbicide. A subsequent survey of commercially available ryegrass seed found that 58% of these samples were resistant to at least 1 herbicide. As a result of these findings, a commercial testing service was established and has since received samples from a large proportion of the southern Australian cropping belt. Seventy-seven percent of samples tested were resistant to Group AI, 40% to Group B and 22% to Group AII Herbicides. Lower levels of resistance were found to Group D (8%), Group C (1%) and Group M (0.4%) Herbicides. The correlation between resistance in Group AI and AII Herbicides was lower than expected given that these Herbicides are considered to have the same mode of action. Within the Group AI Herbicides the observed response of the samples was consistent across herbicide formulations. Resistance to clethodim varied from observed responses to other Group AII Herbicides. The variation in resistance levels (and degree of multiple resistance) in each Australian state is discussed in relation to environmental conditions and cultural practices. The size of this dataset allows for the analysis of the relationships present among herbicide resistant annual ryegrass.

Vidal, Ribas Antonio - One of the best experts on this subject based on the ideXlab platform.

  • Occurrence and importance of herbicide resistance caused by degradation enhancement for weed management
    'Revista Brasileira de Herbicidas', 2016
    Co-Authors: Dalazen Giliardi, Markus Catarine, Kaspary, Tiago Edu, Pisoni Alexandre, Gallon Mateus, Andrew Rerison Silva De ,queiroz, Vidal, Ribas Antonio, Merotto Júnior Aldo
    Abstract:

    A resistência a herbicidas causada por mecanismos não relacionados ao local de ação (NRLA), principalmente causada pelo incremento de metabolização, é altamente problemática devido à ocorrência de biótipos com resistência múltipla, e é um novo desafio para o manejo de plantas daninhas e utilização de herbicidas. Recentemente, enzimas associadas à degradação de xenobióticos, especialmente citocromo P450, GSTs e transportadores ABC, têm sido associadas à resistência a herbicidas em várias plantas daninhas. Os objetivos desta revisão são descrever o conhecimento atual da regulação gênica associada à resistência a herbicidas causada pelo incremento de metabolização e analisar as principais implicações deste problema para definir estratégias adequadas de manejo com o uso de herbicidas. A resistência múltipla a herbicidas causada pelo incremento da degradação ocorre em Lolium rigidum, Alopecurus myosuroides, Echinochloa phyllopogon e outras várias espécies. O nível de resistência a herbicidas causada pelo incremento de metabolização é afetado por fatores ambientais em vários casos, o que dificulta o diagnóstico da resistência e facilita sua distribuição. O manejo moderno de plantas daninhas deve considerar as características de degradação do herbicida, uma vez que a simples rotação de mecanismo de ação de herbicidas pode não ser suficiente para prevenir a ocorrência da resistência a estes produtos. A utilização de misturas sinergísticas de herbicidas e outros inibidores enzimáticos pode contribuir para prevenir a evolução e distribuição da NRLA em plantas daninhas.Non-target-site resistance (NTSR) to Herbicides mainly caused by enhanced degradation is highly problematic due to the occurrence of biotypes with multiple resistance and is a new challenge for weed management and herbicide use. Recently, enzymes associated with xenobiotic degradation especially cytochrome P450, GSTs and ABC transporters have been associated with the herbicide resistance in several weeds. This knowledge opens a new window to understand the evolution of NTSR. The aims of this review are to discuss the current knowledge of the gene regulation associated with the herbicide resistance caused by enhanced herbicide degradation and to analyze the main consequences of this problem for the adequate herbicide use and weed management. Multiple herbicide resistance caused by degradation enhancement occurs in Lolium rigidum, Alopecurus myosuroides, Echinochloa phyllopogon and in several other species. The level of herbicide resistance caused by degradation enhancement is affected by environmental factors in several cases, which difficult the resistance diagnostic and facilitate its distribution. The modern weed management should consider the characteristics of the herbicide degradation, since the simple rotation of Herbicides mechanism of action might not be enough to prevent the herbicide resistance. The use of synergistic mixtures of Herbicides and other enzyme inhibitors may contribute to prevent the evolution and spreading of NTSR weed herbicide resistance

  • Reduction of Alexander grass (Urochloa plantaginea) infestation with aplication of residual Herbicides on common bean
    2014
    Co-Authors: Kalsing Augusto, Vidal, Ribas Antonio
    Abstract:

    O objetivo deste trabalho foi avaliar os efeitos de herbicidas residuais, aplicados na condição de pré-emergência da cultura, na redução da infestação de papuã (Urochloa plantaginea) no feijoeiro comum. Realizaram-se dois experimentos em campo, em Eldorado do Sul, RS, sendo um conduzido com o cultivar UFT - 06 (grupo Carioca) e o outro com o cultivar IPR Graúna (grupo Preto). Os experimentos foram instalados em blocos casualizados, com quatro repetições, testando-se quatro herbicidas residuais em duas doses, mais testemunha sem controle da infestante. Esses herbicidas, com as respectivas doses (kg i.a. ha-1), foram pendimethalin e trifluralin (1,2 e 1,4) e dimethenamid e S-metolachlor (1,4 e 1,6). O controle e a massa seca da parte aérea do papuã foram avaliados aos 20 e 40 dias após a emergência da cultura, o que compreende o período crítico de interferência das infestantes. Os quatro herbicidas testados reduziram a infestação do papuã no feijoeiro comum em relação à testemunha, sendo os melhores níveis de eficácia de controle obtidos com trifluralin. Para se obter sucesso na redução da infestação do papuã com herbicidas residuais, devem-se combinar outras ações de manejo em pós-emergência da cultura do feijão comum.This work evaluated the effects of residual Herbicides, applied in crop pre-emergence, on the reduction of Alexander grass (Urochloa plantaginea) infestation in the common bean. Two field experiments were conducted at Eldorado do Sul, RS/Brazil: one using the bean cultivar UFT-06 (Red group), and the other using IPR Graúna (Black group). The experiments were arranged in a randomized block design, with four replicates, and the treatments consisted of four Herbicides, at two rates (kg i.a. ha-1), as follows: pendimethalin and trifluralin (1.2 and 1.4), and s metolachlor and dimethenamid (1.4 and 1.6). Control and shoot mass of Alexander grass were assessed at 20 and 40 days after crop emergence, which includes the critical period of weed interference. All residual Herbicides reduced Alexander grass infestation during this period, and the best weed control was obtained with trifluralin herbicide in both experiments. To successfully reduce Alexander grass infestation with residual Herbicides, weed management actions must be taken during common bean post-emergence

  • Exploration of herbicide associations to prevent glyphosate tolerant and resistant weeds
    2013
    Co-Authors: Vidal, Ribas Antonio, Rainero, Hector P., Kalsing Karina, Trezzi, Michelangelo Muzell
    Abstract:

    El intenso empleo de glifosato contribuyó a la difusión de malezas con tolerancia a este herbicida, incluyendo especies como Ipomoea nil, bejuco en Argentina, o corriola, o corda-de-viola en Brasil. A su vez, el uso intensivo de imadozolinonas en ciertas regiones de Argentina contribuyó a la aparición de biotipos resistentes a herbicidas que actúan inhibiendo la enzima ALS como Amaranthus quitensis, yuyo colorado o ataco, conocido como carurú en Brasil. En ese país, también, aumentó la difusión de malezas con resistencia a glifosato como en Euphorbia heterophylla, leiteiro o amendoim-bravo y en Lolium multiflorum, azevém. El objetivo de esta investigación fue evaluar el antagonismo o el sinergismo de todas las combinaciones posibles entre dos de los siguientes herbicidas: glifosato, imazetapir, clomazone y lactofen, en el control de las malezas mencionadas. Biotipos susceptibles para todos herbicidas fueran usados en la investigación. Plántulas de yuyo colorado juveniles con dos cm de altura y de las otras malezas mencionadas con siete cm, fueron tratadas con los siguientes herbicidas en g ha-1 i.a.: glifosato 108; imazetapir 10; clomazone 160 y lactofen 30, aplicados solos. Otros seis tratamientos fueron incluidos en todas las combinaciones posibles entre dos de los herbicidas y dosis mencionados. También se empleó un testigo sin tratar. El efecto de la combinación de los herbicidas dependió de la especie evaluada y también de los herbicidas utilizados. Se obtuvo sinergismo solamente para la mezcla glifosato más imazetapir en ataco. Clomazone fue el herbicida con más antagonismo, y lactofen tuvo efecto neutro en la mayoría de las mezclas. Las combinaciones son consideradas potencialmente útiles en el control de malezas tolerantes o resistentes a glifosato.The intense use of glyphosate in Argentina has increased the spread of weeds with tolerance to this herbicide, like Ipomoea nil. Cases of weed resistance to ALS inhibitors were documented in Argentina with Amaranthus quitensis. Likewise, in Brazil, it has increased weed resistance to glyphosate in weeds such as Lolium multiflorum and Euphorbia heterophylla. The objective of this research was to assess antagonism or synergism to control of the mentioned weeds for all possible combinations between two of the following Herbicides: glyphosate, imazethapyr, clomazone, and lactofen. Biotypes susceptible to all Herbicides were used in the research. Seedlings of A. hybridus with two cm and of the others with seven cm, were treated with the Herbicides glyphosate, imazethapyr, clomazone and lactofen at 108, 10, 160 y 30 g ha-1 a.i. respectively, applied alone. Six additional treatments were included in all possible combinations between two of the Herbicides and doses as described above. An untreated control was also used. A non-ionic adjuvant at a ratio of 0.2% was added to all treatments, except for the treatment of glyphosate alone and the untreated. The effect of the herbicide mixtures depended on the species tested and also on the Herbicides used. Synergism was obtained only in the mixture glyphosate + imazethapyr. Clomazone resulted predominantly in antagonism, and lactofen had a neutral effect in most of the evaluated herbicide mixtures. Herbicide combinations are considered potentially useful in controlling weeds resistant or tolerant to glyphosate

  • Weed control with chloroacetamide Herbicides in conventional and no-tillage systems
    2013
    Co-Authors: Ferri, Miguel Vicente Weiss, Vidal, Ribas Antonio
    Abstract:

    Os sistemas de manejo do solo podem alterar a bioatividade dos herbicidas cloroacetamidas e influir na sua persistência no solo, seletividade às culturas e eficácia de controle das plantas daninhas. Um experimento foi conduzido na Universidade Federal do Rio Grande do Sul, durante o ano agrícola de 2000/2001, para avaliar a eficácia de controle das plantas daninhas pelos herbicidas cloroacetamidas, em solo Argissolo Vermelho, manejado sob semeadura direta e preparo convencional. Foram avaliados os herbicidas acetochlor e alachlor, cada um na dose de 3.360 g ha-1, metolachlor a 2.400 g ha-1, s-metolachlor a 1.440 g ha-1, s-metolachlor + antídoto à 1.440 e 1.800 g ha-1, respectivamente, além da testemunha sem herbicida, nos sistemas convencionais e semeadura direta. As avaliações foram de eficácia de controle, população de plantas daninhas e matéria seca da parte aérea das plantas daninhas, realizadas aos 30 e 50 dias após aplicação dos tratamentos (DAT). Os herbicidas cloroacetamidas foram mais eficientes no controle das plantas daninhas no preparo convencional, comparado à semeadura direta, em ambas as épocas de avaliação. Os herbicidas acetochlor, alachlor a 3.600 g ha-1 e s-metolachlor + protetor a 2.400 g ha-1 foram mais eficientes no controle destas plantas, em relação aos demais herbicidas e formulações. A produção de matéria seca e a população das plantas daninhas foram menores no preparo convencional.Soil management systems can affect chloroacetamide herbicide bioactivity and its soil persistence, crop selectivity and weed control. An experiment was carried out at the University of Rio Grande do Sul, Brazil, during the growing season 2000/2001, to evaluate the weed control efficacy of the chloroacetamide Herbicides, in a Paleudult soil, under conventional tillage and notillage systems. The following treatments were tested: acetochlor and alachlor, each at the rate of 3.360 g ha-1, metolachlor at 2.400 g ha-1, s-metolachlor at 1.440 g ha-1, and s-metolachlor + protector at 1.440 and 1.800 g ha-1, respectively, besides a check plot without herbicide, applied under conventional and no-tillage systems. Assessments included weed population, weed dry matter and weed control at 30 and 50 days after herbicide application. The chloroacetamides Herbicides were more effective in controlling weeds under conventional tillage, compared to no tillage, in both evaluation times. The Herbicides acetochlor, alachlor at 3,600 g ha-1 and metolachlor + protector at 2,400 g ha-1 were more efficient in controlling these plants when compared to the other Herbicides and formulations. Dry biomass production and weed populations were lower under conventional tillage