Arthur Barroso

Universidade Federal do Paraná | UFPR · Departamento de Fitotecnia e Fitossanitarismo

Mapping resistant populations makes it possible to identify the evolution and dispersal of resistance cases, providing important information for control-related decision making. This study aimed to identify and map herbicide-resistant sourgrass (Digitaria insularis) populations in Brazilian regions. The results showed no glufosinate resistance, wit...

With the increasing reports of decreased effectiveness of herbicides in controlling Digitaria insularis, Bidens subalternans, Chloris elata and Amaranthus hybridus, as well as officially reported cases of resistance, it is believed that there may be biotypes of these species with herbicide resistance in Paraguay. This study aimed to monitor D. insu...

The objective of this work was to evaluate the effectiveness of herbicides when applied alone and in combinations at sourgrass (Digitaria insularis) post-emergence, as well as to identify a substitute to paraquat in sequential application. Field and greenhouse experiments were conducted during the 2019/2020 and 2020/2021 crop seasons. The herbicide...

O sulfentrazone é comumente aplicado em pré-emergência da soja. Inclusive estudos mais recentes também observaram a sua seletividade para a soja, quando aplicado em pré-mistura formulada com diuron. Objetivou-se avaliar a seletividade de sulfentrazone + diuron (Stone®) na dessecação pré-semeadura da soja em solo argiloso ou arenoso. Foi aplicado su...

A dessecação pré-colheita da soja é uma prática que pode ser adotada com o objetivo de controlar as plantas daninhas ou uniformizar as plantas com problemas de haste verde/retenção foliar, bem como antecipar e/ou otimizar a colheita, e redução dos danos oriundos de pragas e fungos que possam atacar a cultura no final do ciclo. Objetivou-se com este...

Estudos caracterizam o uso do clomazone em pré-emergencia para o manejo de plantas daninhas em soja. Alguns poucos estudos indicam a seletividade do mesmo na aplicação em pós-emergencia. Objetivou-se avaliar a eficácia no controle de plantas daninhas e seletividade de clomazone em formulação inovadora (Reator ® 360 CS), para a aplicação em pré e/ou...

O clomazone é seletivo em pré-emergência da soja, mas em pós-emergência os resultados são menos consolidados. Portanto apresenta-se a necessidade de estudos com aplicação de clomazone em pós-emergência da soja. Objetivou-se avaliar a eficácia e seletividade de clomazone em formulação inovadora (Reator), e outros herbicidas, isolados e em misturas p...

A investigação de carfentrazone em misturas, na primeira ou segunda aplicação da dessecação pré-semeadura da soja, é importante. Objetivou-se avaliar a eficácia de carfentrazone na primeira aplicação em associação com glyphosate + triclopyr, e na segunda aplicação em associações com diquat ou glufosinate. Os tratamentos foram compostos pela primeir...

A utilização de herbicidas de diferentes mecanismos de ação, misturas e adoção de outras ferramentas além do controle químico são fundamentais na prevenção da seleção de biótipos de plantas daninhas resistentes, assim como no manejo delas. Objetivou-se avaliar a eficácia de herbicidas, isolados e em misturas, no controle de trapoeraba e buva, no pe...

Eleusine indica é uma planta daninha de difícil controle com herbicidas pós-emergentes devido ao curto intervalo entre a emergência e o perfilhamento, em que o controle é mais limitado. Ademais, o surgimento de biótipos resistentes motiva realizar trabalhos desta natureza para encontrar mais opções de controle químico. O objetivo desta investigação...

The Sumatran fleabane (Conyza sumatrensis [Retz.] E. Walker) and Benghal dayflower (Commelina benghalensis L.) are among the most challenging weeds to control in agricultural crops. However, synthetic auxins present a potential solution. This study aimed to assess the efficacy of auxin herbicides in controlling C. sumatrensis and C. benghalensis us...

Monitoring herbicide-resistant weeds makes it possible to study the evolution and spread of resistance, which provides important information for their management. The objective of this study was to map fleabane accessions in the states of Paraná (PR) and Mato Grosso do Sul (MS), Brazil, to identify herbicide-resistant accessions and their response...

Second-generation glyphosate-tolerant maize (Roundup Ready 2, RR2) is characterised by the expression of the cp4epsps gene. Despite some studies suggesting possible undesirable effects from the application of glyphosate in RR2 maize, other reports have demonstrated glyphosate selectivity for RR2 plants, with minor damage symptoms, if any, and with...

Pre-emergence herbicides can be effective in controlling Sumatran fleabane (Conyza sumatrensis [Retz.] E.Walker) at soybean and other crops. The goal was to evaluate the effectiveness of sulfentrazone/diuron, imazethapyr/flumioxazin, flumioxazin, diclosulam, s-metolachlor, imazethapyr, clomazone and imazapic/imazapyr in controlling Sumatran fleaban...

The objective of this review is to bring information about innovations and technologies that, through genetic improvement, are being used to improve the sustainability and productivity of agricultural crops, improve human nutrition, as well as conservation and decontamination of soils. Bioremediation consists of using microorganisms that have the a...

BACKGROUND Transgenic event DAS44406‐6 (E3) makes soybeans that are herbicide [glyphosate (Gly), 2,4‐dichlorophenoxyacetic acid (2,4‐D) and glufosinate] and caterpillar resistant. The E3 soybean was commercially released for the 2021/2022 harvest in Brazil. We conducted this study to test whether Gly and 2,4‐D applied alone and in a commercial mixt...

2,4-D or dicamba can cause injuries and other deleterious effects on non-tolerant soybeans. Thus, the objective was to evaluate the potential for injury of subdoses of 2,4-D or dicamba, in drift simulation, for application in non-tolerant soybeans. Two experiments were carried out, one with 2,4-D and the other with dicamba. The treatments consisted...

The silvopastoral system presents benefits in comparison to the pastoral system, being considered an alternative for livestock production. However, little is known about the occurrence of spontaneous plants in these systems, which can be either weeds or plants desirable for grazing. This study monitored, for eight years (2014–2021), the dynamics of...

The intensive global use of glyphosate has led to the evolution of glyphosate resistant (GR) weed species, including the economically damaging horseweed (Conyza sumatrensis). We evaluated the glyphosate resistance mechanisms of C. sumatrensis. While 5-enolpyruvylshikimate-3-phosphate synthase activity was similar between the glyphosate resistant (G...

The intensive global use of glyphosate has led to the evolution of glyphosate resistant (GR) weed species, including the economically damaging horseweed (Conyza sumatrensis). We evaluated the glyphosate resistance mechanisms of C. sumatrensis. While 5-enolpyruvylshikimate-3-phosphate synthase activity was similar between the glyphosate resistant (G...

Introdução: A planta daninha Spermacoce verticillata pode ser problemática para o milho, sobretudo quando este for cultivado em primeira safra. Neste contexto é importante investigar a seletividade de herbicidas, bem como sua eficácia. Objetivo: Avaliar a eficácia de atrazina, saflufenacil, flumioxazina, carfentrazona e bentazona no controle de S....

BACKGROUND Eleusine indica (L.) Gaertn. (goosegrass) is a major weed in global cropping systems. It has evolved resistance to glyphosate due to single Pro‐106‐Ser (P106S) or double Thr‐102‐Ile + Pro‐106‐Ser (TIPS) EPSPS target site mutations. Here, experiments were conducted to evaluate the single effect of soybean competition and its combined effe...

Residual herbicides and cover crops are important tools inside an integrated weed management program. The straw produced in crop rotation can interacts with herbicides. The aim of this study was to evaluate the interaction of diclosulam, sulfentrazone, imazethapyr, flumioxazin, s-metolachlor and pyroxasulfone with black oat, cereal rye, common vetc...

O uso de associações de herbicidas, entre outras práticas são fundamentais no manejo de buva (Conyza spp.). Acredita-se que utilização, na entressafra, de atrazine/mesotrione em associação com auxinas sintéticas, com aplicação sequencial seja eficaz no manejo da buva. Objetivou-se avaliar a eficácia de atrazine/mesotrione em associação com auxinas...

ABSTRACT Weed competition is a challenge to rice monocropping growers in the context of herbicide resistant weeds and difficult weeds to manage using chemical control. Diversifying crop rotations through integrated crop-livestock systems (ICLS) can be an alternative to face this challenge. As weed seedbank reflects management practices, this study...

Even though glyphosate resistance in tall windmill grass (Chloris elata Desv.) was initially reported in 2014, the resistance mechanisms have not yet been completely elucidated. Previous research found evidence of a non‐target site mechanism limiting the herbicide from reaching its enzyme target. We investigated the foliar morphology of tall windmi...

O objetivo da aplicação de um herbicida é atingir o alvo com quantidades determinadas de calda e ingrediente ativo, tendo a menor quantidade de produto perdido possível. Contudo, por vários fatores, têm-se perdas para o ambiente, uma delas é a deriva, que é todo volume de calda que não atinge o alvo ou é perdido para o ambiente, onde, além de danos...

Os herbicidas do grupo das auxinas sintéticas, como o 2,4-D, afetam as plantas de maneira semelhante a auxina ácido indolacético. O objetivo da aplicação de um herbicida é atingir o alvo com quantidades determinadas de calda e ingrediente ativo, tendo a menor quantidade de produto perdido possível. Contudo, por vários fatores, têm-se perdas para o...

A falta de informações e resultados mais pontuais sobre o manejo e condução dos sistemas de integração milho-braquiária, causam pouco interesse por parte dos produtores. Problema esse que pode ser revertido partindo da divulgação de dados sobre o ganho de produtividade e o retorno financeiro ocasionado pela diminuição de insumos nas áreas de cultiv...

A interferência de plantas daninhas na cultura do amendoim é um dos principais fatores limitantes do crescimento, desenvolvimento e produtividade da cultura. Em virtude disso, a busca por alternativas para o controle de plantas daninhas é necessária para realização do manejo da cultura. Desta forma, objetivou-se avaliar os efeitos fitotóxicos de di...

Weeds are a concern to farmers mainly by reducing crop yield, especially in organic farming where herbicides are not an option. Additionally, reducing reliance on herbicides is among the goals to achieve sustainable crop production. By investigating alternatives for weed control, several studies have shown that grassland is more competitive with we...

Chloris elata is an important weed for grain and sugarcane crops. In addition to its aggressiveness, it may show resistance to glyphosate herbicide. In this context, the aim of this study was to assess the effectiveness of glyphosate formulations, isolated or in association with ACCase inhibitors, in controlling C. elata (putatively resistant to gl...

Weed densities, species, costs of control, crop value and interference periods should be considered for weed management. With this regard, three experiments were carried out to evaluate weed control periods and weed density in a new soybean cultivar. In ths first trial, control efficacy was measured by visual phytotoxicity of four weed species I. h...

Sourgrass (Digitaria insularis) is one of the main weeds in the soybean crop. In order to control its growth, an increase of herbicide rates is required to simplify its management as it a plant with high vegetative capacity and seed production. It implies to select the herbicide-resistent Digitaria insularis biotypes. Nevertheless, some information...

Together, Conyza bonariensis, C. canadensis and C. sumatrensis show 105 reported cases of biotypes resistant to herbicides like glyphosate, paraquat, and acetolactate synthase (ALS) inhibi-tors. The application of pre-emergent herbicides combined with burndown herbicides is believed to be effective in controlling Conyza spp. during soybean pre-sowi...

Crop rotation is critical in the management of herbicideresistant weed species. This study aimed to evaluate the effect of intercropping systems of maize with brachiaria or crotalaria on qualitative and quantitative parameters of the weed seedbank, along the succession of pearl millet, maize and common bean. Moreover, the effect of these crop rotat...

Herbicide mixtures, use of multiple sites of action, and other weed management practices are necessary to avoid cases of biotype resistance. The aim of this study was to evaluate the efficiency of imazapic/imazapyr and other herbicides in mixtures to control Digitaria insularis at burndown before soybean sowing. This field research was conducted in...

This study characterized the germination of seeds of Chloris polydactyla (synonymy Chloris elata) and Chloris barbata at varying temperature, luminosity, soil texture and cover. The first experiment was conducted in laboratory to determine the temperature and light effects on germination of these species. The experimental design was a 2x7 factorial...

The seed germination and the early plant growth of corn (Zea mays) and soybean (Glycine max) sowed after cropping and under straw residues (simulating crop rotations) of oat (Avena sativa), ryegrass (Lolium multiflorum) and wheat (Triticum aestivum) were investigated in pot experiments carried out under controlled conditions. The germination rates...

Sugarcane is one of the main agricultural cultivations of Brazil, and one of the crops in which herbicides are most applied. In the 2017/2018 season, the estimated sugarcane production was 694.54 million tons, with an estimated increase of 0.9% in yield for this season. In order to evaluate the use of herbicides in this crop in the São Paulo State...

Weeds reduce the productive potential of crops. Plants of the Ipomoea genus, besides competing for water, light, space and nutrients, create problems in crop harvests due to their volatile stems. The objective of this work was to evaluate the growth and development of five Ipomoea species. For such, Ipomoea grandifolia, Ipomoea hederifolia, Ipomoea...

Herbicide resistant is associated with morphological, physiological and metabolic alterations in weeds. These alterations may reflect changes in the nutritional status of resistant plants and their growth it can be inferred in greater adaptability and competitive ability of the resistant biotypes. Thus, the objective of this research was to determi...

Abstract The new technology of sugarcane planting, known as one-eye-set seedlings, offer a high standard of plant health and vegetative vigor. However, there are no reports in the literature that evaluate the weed competition with one-eye-set sugarcane seedlings, and the periods in which weed communities need to be controlled in this system. Two in...

Glyphosate is the most used herbicide worldwide and glyphosate-tolerant soybean planted in almost all cultivated areas. In Brazil, the area cultivated with transgenic soybean reaches more than 90%. Recently, the application of glyphosate in tolerant soybean has assumed the possibility to injury the crop under certain conditions and herbicides formu...

The repetitive use of herbicides with the same mechanism of action causes the selection of resistant weeds, such as ryegrass. Considering the occurrence of ryegrass (Lolium multiflorum) in eucalyptus, a crop on which glyphosate is used, it is necessary to study its interference. The objective of this study was to evaluate the effect of densities (0...

Herbicide resistant plants may present changes in their physiology and aggressiveness. In order to evaluate the competitive differences of glyphosate resistant ryegrass, in a first experiment, resistant and susceptible biotypes grew in intra and interbiotypic competition in different environmental conditions (check, irradiance and water deficit). I...

Weed interference reduces the productive potential of crops. Among the control methods used, chemical ones occupy a major position. The repeated application of the same mechanism of action selects tolerant plants. Among the species that affect sugarcane, crabgrass is one of them. This study has aimed to know the tolerance of different populations o...

Glyphosate has been associated with control failures for Spermacoce verticillata in some Brazilian States. The objective of this work was to evaluate and determine the possible causes of this and propose alternative herbicides to use. Glyphosate was applied at three plant stages of development (2–4 leaves, 4–6 leaves and full bloom) where foliar ab...

The benefits of glyphosate tolerant crops technology are well-known, and its acceptance by farmers is undeniable. However, results of recent research indicate that, in some situations, glyphosate applied to herbicide-tolerant soybean crops may have phytotoxic effects affecting nutritional balance, photosynthesis and others biochemical process in pl...

Background: Weeds reduce crop yields, and among the methods used to control these plants, chemical use is preferred. However, the repeated application of herbicides with the same mechanism of action selects for resistant populations. The aim of this study was to evaluate glyphosate resistance in Lolium multiflorum (Lam.) and relate the resistance...

This research was carried out to evaluate the interference periods and phytosociological indexes of the weed community on sweet sorghum, hybrid CVSW 80007, cultivated for two seasons in a year. The treatments were based on an increased duration of weed presence and weed absence after sowing (0, 4, 7, 14, 21, 28, 35, 42, 56 and 68 days after crop em...

Sourgrass is one of the most problematic weeds of Brazil. It is an aggressive species in the allocation of resources from the environment and reported to be glyphosate resistant in several states of the country. This work has aimed to verify environmental effects on seed germination and seedling emergence of sourgrass. Laboratory and field trials w...

Allelochemicals are important and innovative tools for weed control as they neither harm the environment nor increase weed management costs. The secondary metabolites can be extracted by water or soaking and later applied in soil or leaves. This study evaluated the leaf extracts of Cymbopogon citratus, affecting germination of Bidens pilosa and B....

The objective was to determine whether a change occurs in the critical period of weed interference prevention in narrow row corn with the use of atrazine and whether there is influence of the herbicide on crop yield components. The treatments consisted of periods without or with an initial weed control (0, 21, 35, 49, 63, 77, and 91 days after emer...

Weed herbicide resistance has been a challenge in agriculture. The objective of this study was to detect sourgrass (Digitaria insularis (L.) Fedde) glyphosate-resistant plants and to evaluate the growth and polymorphism rate between the resistant and susceptible biotypes, as a subsidy for the integrated management of species. An experiment was cond...

The interference of weeds in maize production may be reflected in grain yield losses that vary as a function of the density, stage and degree of aggressiveness of the species present. In the agricultural ecosystem, crops and weeds demand light, water, nutrients and space, which are frequently not available in sufficient quantities, leading to compe...

O surgimento de plantas daninhas resistentes tem aumentado os custos e prejudicado a produção dos cultivos pela interferência de plantas daninhas com o cultivo e perda de efetividade dos herbicidas de ampla utilização com amplo espectro de controle e baixo custo, como o glyphosate. Deste modo, o trabalho objetivou identificar populações de C. polyd...

Weed resistance to herbicides is a natural phenomenon that exerts selection on individuals in a population. In Brazil, glyphosate resistance was recently detected in Digitaria insularis. The objective of this study was to elucidate mechanisms of weed resistance in this plant, including genetic variability, allelism, amino acid substitutions, gene e...

Sourgrass(Digitaria insularis, L. Mez ex Ekman)is a weed that requires high rates of glyphosate ((N-[phosphonomethyl]-glycine) forcontrol, verylittle of the herbicide applied isabsorbed by theleaves. Morphological and histological differences in leaves of glyphosate-resistant and glyphosate-susceptible plantsshould explain the contrast of variance...

To gain a better understanding of the physiology of the herbicide aminocyclopyrachlor in young plants of trumpet flower, the uptake and translocation were evaluated after the application of herbicide. This was determined by treating individual leaves with formulated herbicides plus (14)C-aminocyclopyrachlor after the application of the formulated h...

A luz, a temperatura e a dormência são fatores que influenciam a germinação das sementes e estão estritamente ligados à emergência de plantas daninhas. Objetivou-se com este trabalho avaliar a germinação de Sorghum arundinaceum e Sorghum halepense submetidas a diferentes condições de temperatura e luminosidade, bem como avaliar mecanismos de quebra...