Fitness of Echinochloa crusgalli var. mitis biotypes susceptible and resistant to imazapyr + imazapic herbicide

The continuous use of herbicides with the same mechanism of action has caused the selection of resistant weed biotype that may present differences in fitness when compared with susceptible biotype. The objective of the present study was to identify and distinguish the fitness of barnyardgrass biotypes resistant and susceptible to imazapyr + imazapic herbicide under controlled and noncompetitive conditions. For that, there were used barnyardgrass biotype susceptible (ECH1 and ECH38) and resistant (ECH14 and ECH44) to ALS inhibitors, collected at Pelotas/RS and Rio Grande/RS cities, respectively, in experiment installed in a greenhouse in a completely randomized experimental design during the months from October to December 2015. The biotype were evaluated during the period of 15 to 120 days after the emergence related to plant height, foliar area, shoot dry matter mass and root dry matter mass. The results showed insignificant differences between the biotypes during the development of the plants. The susceptible biotype ECH44 showed a higher number of panicles per plant and seeds along with the resistant ECH1. There is variability among Echinochloa crusgalli var. mitis biotypes resistant and susceptible to ALS inhibitors, indicating an absence in fitness penalty caused by resistance when cultivated without the selection of pressure (herbicide).

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Geographic Distribution of Ryegrass Resistent to the Clethodim Herbicide in Rio Grande do Sul1

Planta Daninha ◽

10.1590/s0100-83582016340200018 ◽

2016 ◽

Vol 34 (2) ◽

pp. 365-376

Author(s):

L. VARGAS ◽

T. SCHNEIDER ◽

D. AGOSTINETTO ◽

M.A. BIANCHI

Keyword(s):

Geographic Distribution ◽

Annual Cycle ◽

Rio Grande ◽

Rio Grande Do Sul ◽

Action Mechanism ◽

The North ◽

Winter Crops ◽

Glyphosate Herbicide ◽

Continuous Use ◽

Selection Of

ABSTRACT Ryegrass is a weed of annual cycle that is present in winter crops, in orchards and vineyards of the South region of Brazil. The species is normally controlled by the glyphosate herbicide, but the continuous use of this product caused the selection of resistant biotypes. The use of ACCase inhibitor herbicides is the main alternative for the control of this species, but it has not been satisfactory in some places, thus causing suspicion of resistance to this action mechanism. Thus, the objective of this paper was to evaluate the occurrence and geographic distribution of ryegrass biotypes that are resistant to the clethodim herbicide in the state of Rio Grande do Sul. For that, seeds of ryegrass plants that survived the application of clethodim were collected in crops from the north region of RS, summing up to a total of 152 samples from 72 cities. The biotypes were submitted to the application of 120 g i.a. ha-1 (maximum registered dose) and 60 g i.a. ha-1 de clethodim (half the maximum registered dose). According to the results, among the samples of ryegrass seeds collected, there were no biotypes resistant to the clethodim herbicide when the maximum registered dose was applied and in the stage of three to four leaves. However, there were biotypes with lower susceptibility that survived half the maximum registered dose.

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Characterization of Ethoxysulfuron Herbicide Selectivity in Common Bean Cultivars

Planta Daninha ◽

10.1590/s0100-83582018360100113 ◽

2018 ◽

Vol 36 (0) ◽

Author(s):

F.B. PAGNONCELLI JR ◽

R.A. VIDAL ◽

M.M. TREZZI ◽

M. GALLON ◽

A.P. BRUSAMARELLO

Keyword(s):

Experimental Design ◽

Common Bean ◽

Dry Matter ◽

Enzyme Inhibitors ◽

High Variability ◽

Randomized Experimental Design

ABSTRACT: In literature, there are few studies evaluating the response of different bean cultivars to herbicides, particularly the ALS enzyme inhibitors. The objective of this study was to evaluate the selectivity of common bean cultivars to the herbicide ethoxysulfuron and to select cultivars that are more tolerant to it. An experiment was conducted in a greenhouse, in a completely randomized experimental design with four replications. Factors consisted in 20 bean cultivars (IPR Eldorado, IPR Siriri, IPR Gralha, IPR 81, IPR Uirapuru, IPR Colibri, IPR Tuiuiú, BRS Esplendor, IPR Tangará, IPR Juriti, IPR Corujinha, IPR Andorinha, IPR Curió, BRS Campeiro, BRS Pérola, BRS Notável, BRS Estilo, UTF 3, UTF 5 e UTF 6), and four doses of ethoxysulfuron (0, 50, 100 and 200 g ha-1) were used. At the dose of 200 g ha-1, the reduction of the shoot dry matter of plants ranged from 30 to 80%, indicating that there was high variability in the response of bean cultivars to the herbicide. The bean cultivars classified as more tolerant to ethoxysulfuron are: IPR 81, IPR Uirapuru, BRS Estilo, IPR Gralha and BRS Pérola, while the less tolerant cultivars are: IPR Eldorado, IPR Tuiuiú, IPR Tangará, IPR Curió, UTF 3, UTF 5 and BRS Esplendor.

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Competitiveness of ALS inhibitors resistant and susceptible biotypes of Greater Beggarticks (Bidens subalternans)

Planta Daninha ◽

10.1590/s0100-83582011000200024 ◽

2011 ◽

Vol 29 (2) ◽

pp. 457-464 ◽

Cited By ~ 13

Author(s):

F.P. Lamego ◽

R.A. Vidal ◽

N.R. Burgos

Keyword(s):

Competitive Ability ◽

Germination Rate ◽

Rio Grande ◽

Rio Grande Do Sul ◽

Replacement Series ◽

Relative Growth Rates ◽

Temperature Conditions ◽

Als Inhibitors ◽

The University ◽

Continuous Use

The continuous use of ALS-inhibiting herbicides has led to the evolution of herbicide-resistant weeds worldwide. Greater beggarticks is one of the most troublesome weeds found in the soybean production system in Brazil. Recently, a greater beggarticks biotype that is resistant (R) to ALS inhibitors due to Trp574Leu mutation in the ALS gene was identified. Also, the adaptive traits between susceptible (S) and R to ALS inhibitors biotypes of greater beggarticks were compared. Specifically, we aimed to: (1) evaluate and compare the relative growth rates (RGR) between the biotypes; (2) analyze the seed germination characteristics of R and S biotypes under different temperature conditions; and (3) evaluate their competitive ability in a replacement series study. The experiments were conducted at the University of Arkansas, USA, in 2007 and at Universidade Federal do Rio Grande do Sul (Federal University of Rio Grande do Sul), Brazil, in 2008. Plant proportions for replacement series studies were respectively 100:0, 75:25, 50:50, 25:75 and 0:100, with a total population of 150 plants m-2. There was no difference in RGR between R and S biotypes. The R-biotype germination rate was lower than that of the S biotype. However, at low temperature conditions (15 ºC), the reverse was observed. In general, there is no difference in the competitive ability between R and S greater beggarticks biotypes.

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Uso de diferentes pontas de pulverização no controle de doenças no trigo

Ciência e Natura ◽

10.5902/2179460x35494 ◽

2019 ◽

Vol 40 ◽

pp. 11

Author(s):

Alicia Baumhardt Dorneles ◽

Eduardo Leonel Bottega ◽

Zanandra Boff de Oliveira ◽

Alberto Eduardo Knies ◽

Clarissa Moraes da Silva ◽

...

Keyword(s):

Experimental Design ◽

Environmental Factors ◽

Chemical Control ◽

Rio Grande ◽

Control Plot ◽

State University ◽

Rio Grande Do Sul ◽

Randomized Experimental Design ◽

Management Techniques ◽

Grain Contamination

Unstable environmental factors contribute to the incidence of diseases and pests, causing reduced yield and grain contamination, especially the attack by Giberela (Fusarium graminerum). In this scenario, appropriate management techniques are needed. Strategies such as choosing the suitability of the spray tip for chemical control are indispensable. The aim of this study was to use four spray tips: CVI 11002, ADI ISO 11002, TVI ISO 8002 and ATR 8002. The experiment was conducted in the experimental area of The State University of Rio Grande do Sul, in the district of Três Vendas, in Cachoeira do Sul-RS. The cultivar used was TBIO SELETO. The fungicide used was Nativo®. A completely randomized experimental design with 4 replicates and a control plot was adopted. The following parameters were evaluated: weight of one thousand grains (PMG, %), hectoliter weight (PH; kg hL-1) and yield (PRD; kg ha-1). The variance was tested by applying the Snedcor F test (p<0.05) and the means were compared by the Tukey's test (p<0.05). The weight of one thousand grains, hectoliter weight and yield were not influenced by the use of different spray tips adopted in the wheat phytosanitary control.

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Repeatability estimates and minimum number of evaluations for selection of elephant-grass genotypes for herbage production

Bioscience Journal ◽

10.14393/bj-v36n1a2020-42075 ◽

2020 ◽

Vol 36 (1) ◽

Author(s):

Erina Vitório Rodrigues ◽

Rogério Figueiredo Daher ◽

Geraldo de Amaral Gravina ◽

Alexandre Pio Viana ◽

Maria do Socorro Bezerra de Araújo ◽

...

Keyword(s):

Plant Height ◽

Principal Components ◽

Dry Matter ◽

Block Design ◽

Phenotypic Selection ◽

Stem Diameter ◽

Dry Matter Yield ◽

Elephant Grass ◽

Minimum Number ◽

Selection Of

In forage-plants breeding, the selection of superior genotypes has been undertaken through successive harvests in previously established intervals. However, this process involves many steps, the evaluation of many traits, and a great spending with costs and labor. Thus the estimate of the repeatability is essential in improvement of perennials, it allows predicting genotypic value of the individual, the minimum number of evaluations in the selection of genotypes and minimizes resources and time in the selection of promising individuals. The objective of this study was to estimate the repeatability coefficient for morphological traits in elephant grass and determine the number of evaluations needed for phenotypic selection more efficient. The experimental randomized block design with 53 genotypes and two replications. The repeatability coefficients were estimated for variables plant height, number of tillers, stem diameter and dry matter yield, using the methods of Anova, Principal Components and Structural Analysis. We observed significant differences between genotypes (P <0.01) for all variables. The main components provide larger estimates of repeatability when compared to other methods. Estimates of the repeatability coefficients are of high magnitude average for the variables plant height (0.44) number of tillers (0.44) and stem diameter (0.63) and low magnitude for dry matter production (0.27). The Principal Components method requires five, five, two and eleven measurements for plant height, number of tillers, stem diameter and dry matter yield, respectively, with 80% reliability.

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Nitrogen fertilization in the growth phase of 'Chardonnay' and 'Pinot Noir' vines and nitrogen forms in sandy soil of the Pampa Biome

Revista CERES ◽

10.1590/0034-737x201764040013 ◽

2017 ◽

Vol 64 (4) ◽

pp. 433-440 ◽

Cited By ~ 1

Author(s):

Felipe Lorensini ◽

Carlos Alberto Ceretta ◽

Lessandro De Conti ◽

Paulo Ademar Avelar Ferreira ◽

Max Kleber Laurentino Dantas ◽

...

Keyword(s):

Plant Height ◽

Sandy Soil ◽

Nitrogen Fertilization ◽

Dry Matter ◽

Rio Grande ◽

Pinot Noir ◽

Rio Grande Do Sul ◽

Mineral N ◽

Total N ◽

Pampa Biome

ABSTRACT Information on nitrogen fertilization in growing vines is still a very limited subject, especially for crops on sandy soils in the Pampa Biome in Rio Grande do Sul, where viticulture has expanded considerably in the last decade. This study aimed to assess the impact of N doses on growth of young plants of Chardonnay and Pinot Noir vines and N forms present in sandy soil in the Pampa Biome. The experiment was conducted from October 2011 to December 2012 in a vineyard in Santana do Livramento, in Southern Rio Grande do Sul State, in soil with 82 g kg-1 clay in the 0-20 cm layer. Vines of Chardonnay and Pinot Noir varieties were subjected to applications of 0, 10, 20, 40, 60, and 80 kg N ha-1 year-1. Total N in leaves, SPAD readings, stem diameter, plant height, and dry matter of the pruned material were evaluated in two growth cycles and three times. Soil samples were collected at 0-10 and 10-20 cm depths at four crop growth stages, in which N-NH4 +, N-NO3 -, and total N were analyzed and the mineral N was calculated. The N levels applied to young vines, although they did not provide relevant changes in the N-NH4 +, N-NO3 -, and mineral N contents in the soil, were able to increase the N content in the leaves, increasing plant vigor. because the reason is that there was an increase in stem diameter, plant height, and dry matter of pruned material in most evaluation periods. These parameters suggest better growth patterns and uniformity of young grapevines with possible positive effects in anticipation of production, demonstrating the importance of nitrogen fertilization strategies to the growing vines in the sandy soil conditions of the Pampa Biome.

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Character Association Study Among Components of Green Fodder Yield in Ricebean

Indian Journal of Agricultural Research ◽

10.18805/ijare.v51i04.8425 ◽

2017 ◽

Vol 51 (04) ◽

Author(s):

Monica Jyoti Kujur ◽

S. K. Bilaiya ◽

A.K. Mehta

Keyword(s):

Plant Height ◽

Crude Protein ◽

Dry Matter ◽

Protein Yield ◽

Direct Selection ◽

Path Coefficient ◽

Dry Matter Yield ◽

Green Fodder ◽

Fodder Yield ◽

Selection Of

Ricebean has been categorized as underutilized crop despite its nutritive quality and fodder yielding ability benign higher than other legumes of Vigna family. In addition to its nutritive value, this crop is fairly resistant to drought and flood conditions. The purpose of this paper is to provide important traits for direct selection of fodder yielding ricebean genotypes through analysis of phenotypic and genotypic association and path coefficient. In the present study, the degree of association between yield and yield contributing attributes were estimated in 85 germplasm lines for nineteen quantitative traits so that direct selection of the promising traits may be effective for the improvement of yield potential of future genotypes of ricebean. Correlation studies indicated that green fodder yield per plant was significantly and positively associated with green fodder yield per day, number of leaves per plant, number of branches per plant, crude protein yield per plant, crude protein yield per plant per day, dry matter yield per plant, dry matter yield per plant per day, leaf stem ratio and plant height at both genotypic and phenotypic levels. Path coefficient revealed that green fodder yield per plant per day has highest direct effect and significant positive correlation towards yield. Other traits, crude protein yield per plant, dry matter yield per plant per day, days to 50% flowering, days to flower initiation and plant height were also found to be important fodder yield indicators in ricebean.

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Germination and tolerance of cowpea (Vigna unguiculata) cultivars to water stress

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v22n6p407-411 ◽

2018 ◽

Vol 22 (6) ◽

pp. 407-411 ◽

Cited By ~ 1

Author(s):

Emanoela P. de Paiva ◽

Francisco V. da S. Sá ◽

Salvador B. Torres ◽

Marcos E. B. Brito ◽

Romulo C. L. Moreira ◽

...

Keyword(s):

Water Stress ◽

Experimental Design ◽

Seed Germination ◽

Dry Matter ◽

Euclidean Distance ◽

Development Stage ◽

Dry Matter Accumulation ◽

Initial Development ◽

Cowpea Cultivars ◽

Randomized Experimental Design

ABSTRACT The objective of this study was to evaluate the tolerance of cowpea cultivars to water stress, during seed germination and seedling establishment. For this, a completely randomized experimental design was used in a factorial scheme consisting of nine cultivars of cowpea (BRS Guariba, BRS Potengi, BRS Itaim, BRS 17 Gurguéia, BRS Aracê, Paulistinha, Maratanã, Costela-de-Vaca and Canapu-Branco) and two levels of osmotic potential induced by PEG 6000 (0.0 MPa (control) and -0.4 MPa) in four replicates of 50 seeds. The variables analysed were germination, germination first count, root and shoot lengths, and dry matter accumulation of shoots and roots. The dissimilarity between the genotypes was also determined by Euclidean distance. Germination and initial development of cowpea cultivars are impaired by the reduction in the potential to -0.4 MPa. The cultivars BRS Guariba, BRS Aracê, Paulistinha and Canapu-Branco are the most tolerant to water stress, while BRS Potengi, BRS Itaim, BRS 17 Gurguéia, BRS Maratanã and Costela-de-Vaca are the most sensitive in the early development stage.

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Resistance of Echinochloa crusgalli var. mitis to Imazapyr+Imazapic Herbicide and Alternative Control in Irrigated Rice

Planta Daninha ◽

10.1590/s0100-83582018360100028 ◽

2018 ◽

Vol 36 (0) ◽

Cited By ~ 1

Author(s):

J.F.L. BONOW ◽

F.P. LAMEGO ◽

A. ANDRES ◽

L.A. AVILA ◽

G.M. TELÓ ◽

...

Keyword(s):

Weed Management ◽

Integrated Management ◽

Rio Grande ◽

Integrated Weed Management ◽

Rio Grande Do Sul ◽

Resistance Level ◽

Irrigated Rice ◽

Plant Seeds ◽

Als Inhibitors ◽

Continuous Use

ABSTRACT: The introduction of Clearfield® system for irrigated rice production provided an effective management strategy in the selective control of weeds. However, the selection pressure caused by the continuous use of herbicides such as imazapyr+imazapic belonging to the imidazolinone chemical group, without the proper integrated management of weeds, has favored the selection of resistant accessions. The goals of this work were to confirm the resistance to ALS inhibitors in accessions of E. crusgalli var. mitis collected in rice fields of the state of Rio Grande do Sul and to evaluate the control with alternative herbicides registered for weed control. Three experiments were conducted in a greenhouse using plant seeds that survived the application of the herbicide imazapyr+imazapic, collected in irrigated rice producing regions with suspected resistance escapes. For dose-response curve study, three resistant accessions (ECH1 - Pelotas/Rio Grande do Sul, ECH27 - Arroio Grande/Rio Grande do Sul and ECH38 - Rio Grande/Rio Grande do Sul) and two susceptible accessions (ECH14 - Pelotas/Rio Grande do Sul and ECH44 - Rio Grande / Rio Grande do Sul) (factor A) and 11 doses of the herbicide imazapyr+imazapic (factor B) were selected. The results indicate that barnyardgrass resistant accessions present a high resistance level to imazapyr+imazapic. ALS inhibiting herbicides such as imazethapyr+imazapic, bispyribac-sodium and penoxsulam did not control the resistant accessions either. Integrated weed management should be adopted and alternative mechanisms of action as ACCAse (cyhalofop-butyl, profoxydim and clethodim) and EPSPS (glyphosate) inhibitors are still eficients controlling barnyardgrass ALS resistant accessions.

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Effect of different double-sided plastic films on chemical and fermentation characteristics of corn silage

Ciência Animal Brasileira ◽

10.1590/1809-6891v22e-66770 ◽

2021 ◽

Vol 22 ◽

Author(s):

Fernando Braga Cristo ◽

Mikael Neumann ◽

Fernando de Souza Sidor ◽

Maria Eduarda Cozechen Seller ◽

Daniel Corrêa Plodoviski ◽

...

Keyword(s):

Experimental Design ◽

Dry Matter ◽

Corn Silage ◽

Plastic Films ◽

Dry Matter Digestibility ◽

Aerobic Stability ◽

Randomized Experimental Design ◽

Polyamide Film

Abstract The objective of this study was to evaluate the efficiency of different double-sided plastic films on chemical and fermentation characteristics, dry matter digestibility, aerobic stability, physical and dry matter losses in corn silages stored in bunker silos. This was a completely randomized experimental design consisting of three treatments: DF110µm - double-sided polyethylene with 110 µm thickness; DF200µm - double-sided polyethylene with 200 µm thickness; and DFBO - oxygen-impermeable film consisted of double-sided polyethylene with 80 µm thickness overlaid with a translucent vacuum polyamide film with 20 µm thickness. The use of DF200µm film increased the ruminal dry matter digestibility by 4.58% and reduced the silage temperature by 3.1 °C, as well as the physical losses of the corn silage were reduced by 118.9 g kg-1 DM using DFBO and 95 g kg-1 DM with DF200µm; DFBO resulted in the highest aerobic stability (127 hours) of corn silage. The use of DF200µm and DFBO is recommended for preserving corn silage in bunker silos.

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