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The resistance of a weed to a herbicide may be accompanied by an ecological disadvantage, which can hinder the establishment of resistant biotypes when the herbicide is not used. Th e aim of this study, therefore, was to evaluate the growth and phenology of two biotypes of Raphanus raphanistrum, one susceptible and the other resistant to ALS inhibitors. The research was carried out from August to December 2020, conducting two simultaneous experiments, with the susceptible and resistant biotypes grown as single crops or together with wheat. The parameters under evaluation were plant height, number of leaves, leaf area, shoot dry weight, growth rate, leaf area ratio, net assimilation rate, and phenology -- determined using the BBCH scale. The results showed not only that development and growth in the sensitive biotype was greater compared to the resistant biotype, but also the precocity of the biotype. The only variable for which the resistant biotype was superior was root dry weight. Cross-resistance to ALS inhibitors resulted in a difference in the growth and phenology of the resistant biotype that should be better evaluated, as the populations present large genetic differences. [ABSTRACT FROM AUTHOR]

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The metsulfuron-methyl is a soil persistent herbicide and can affect the development and yield of sensitive crops grown in succession. The objective this study was evaluate the effect of the application of metsulfuron-methyl at different intervals before sowing on corn development and yield and determine a safe period between the application of the metsulfuron-methyl and corn sowing. The assay was conducted in the 2017/18 and 2018/19 seasons. The experimental design was of randomized blocks, with thirteen treatments and four replicates. The treatments were arranged in factorial scheme (2 x 6) + 1. The first factor consisted in doses of metsulfuron-methyl (1.98 and 3.96 g ha-1). The second factor in intervals between the application of the herbicide and corn sowing (0, 15, 30, 45, 60, and 75 days), plus a control with no herbicide application. The phytotoxicity, yield, and yield components of corn were assessed. The highest phytotoxicity occurred at 3.96 g ha-1, when the herbicide was applied on the day of sowing. Metsulfuron-methyl caused phytotoxicity and reduced corn yield. The safe interval between metsulfuronmethyl application and corn sowing was 15 and 30 days for the doses of 1.98 and 3.96 g ha-1, respectively. [ABSTRACT FROM AUTHOR]

Chemical control is the main weed control method in garlic crops; however, this crop is sensitive to herbicides, which can cause injuries and decrease yield depending on the products used, application timing, rate, and cultivar. In this context, the objective of this study was to evaluate the selectivity of herbicides for garlic plants (cultivar Chonan), using different application timings. A greenhouse experiment was conducted in a completely randomized design with four replications. An 8×2 factorial arrangement was used, in which the first factor consisted of a control without herbicide and seven herbicides (linuron, diuron, pendimethalin, s-metolachlor, oxyfluorfen, flumioxazin, and oxadiazon) applied according to the second factor, application timings (preemergence or post-emergence). Phytotoxicity, photosynthetic rate, stomata morphometry, bulb diameter, and crop yield of garlic were evaluated. Pre-emergence applications were more selective than post-emergence applications. The herbicides linuron, diuron, s-metolachlor, and oxadiazon applied at pre-emergence, and s-metolachlor, oxyfluorfen, flumioxazin, and oxadiazon applied at post-emergence were not selective for the Chonan garlic cultivar. Pendimethalin presented the highest selectivity, regardless of the application timing. Oxyfluorfen and flumioxazin applied at pre-emergence and linuron and diuron applied at post-emergence were selective for the cultivar Chonan. [ABSTRACT FROM AUTHOR]

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Copyright of Cientifica is the property of Fundacao de Apoio a Pesquisa e Extensao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Colloquium Agrariae is the property of Asociacao Prudentina de Educacao e Cultura (APEC) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The development of aryloxyphenoxypropionate-tolerant rice cultivars made possible the selective use of these herbicides tank mixed with others. Thus, this research aimed to evaluate the applications of aryloxyphenoxypropionates associated with latifolicides for controlling weedy rice and barnyardgrass. In a greenhouse, the weedy rice and barnyardgrass control were evaluated with treatments composed of doses from the graminicides quizalofop-p-ethyl (0; 37.5; and 75 g ha-1) or haloxyfop-pmethyl (0; 45; and 60 g ha-1), either isolated or with addition of bentazon, saflufenacil, carfentrazone and with no herbicide. In the field, the effect from doses of quizalofop-p-ethyl (37.5 and 75 g ha-1) was tested, either isolated or associated with penoxsulam, bispiribac-sodium, quinclorac, propanil, bentazon, saflufenacil, carfentrazone and penoxsulam + bentazon for controlling weedy rice. When using a tank mix of herbicides from the aryloxyphenoxypropionates group with bentazon, saflufenacil or carfentrazone, there was a predominance of antagonistic interactions for weedy-rice, and additives interactions for barnyardgrass. In the field, the mixtures of quizalofop-p-methyl (75 g ha-1) with penoxsulam, bispiribac, quinclorac, propanil, bentazon, saflufenacil, carfentrazone or penoxsulam + bentazon resulted in excellent control of the weedy-rice. [ABSTRACT FROM AUTHOR]

Copyright of Revista Ciência Agronômica is the property of Revista Ciencia Agronomica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de Ciencias Agroveterinarias is the property of Revista de Ciencias Agroveterinarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista de Ciencias Agroveterinarias is the property of Revista de Ciencias Agroveterinarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Agricultural Sciences / Revista Brasileira de Ciências Agrárias is the property of Universidade Federal Rural de Pernambuco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Metsulfuron-methyl is one of the most used sulfonylurea herbicides, being applied alone in pre-emergence and with a mineral oil (as adjuvant) in post-emergence. In risk assessment of pesticides, ecotoxicity tests have been applied to assess the effects of products and mixtures under laboratory conditions, but they are limited in their ecological relevance when compared to field assessments. Considering the differences between laboratory and field exposure, and the lack of data on the effects of metsulfuron-methyl in natural soils, this study consisted in a set of tests to assess the ecotoxicity of this herbicide applied alone, combined with an adjuvant (mineral oil) and the adjuvant applied alone, both under laboratory and field exposure, with artificial and natural soil respectively. Reproduction tests with four non-target soil invertebrates species were performed in laboratory, while two experiments were performed in field evaluating avoidance behaviour, feeding activity, mesofauna abundance and pesticide residual. Laboratory results showed that metsulfuron-methyl alone is not a threat to soil fauna on the recommended doses. However, the presence of mineral oil as adjuvant showed ecotoxicity to Eisenia andrei, Enchytraeus crypticus and Proisotoma minuta on laboratory tests. Field evaluations indicated that metsulfuron-methyl and the adjuvant do not impaired the feeding activity of the soil fauna. The low abundance of native communities could be related to soil management. Results showed that laboratory and field evaluations are necessary to better understanding of the effects of pesticides to soil fauna and adjuvant addition should be considered on pesticides risk assessment. Graphical abstract Image 1 Highlights • Effects of metsulfuron-methyl (sulfonylurea herbicide) were evaluated to soil invertebrates. • Laboratory tests showed that metsulfuron-methyl alone is not a threat to soil fauna. • Adjuvant addition (mineral oil) caused ecotoxicity to soil invertebrates on reproduction tests. • Non-effects were observed to soil fauna feeding activity in field. • Adjuvants should be considered on pesticides risk assessment. [ABSTRACT FROM AUTHOR]

Sumatran fleabane is an important weed in Brazilian crop production systems due to glyphosate resistance and broad adaptation to no-till environments, mainly in the crop succession with soybean sowed in first-season (September to February) followed by maize in second-season (February to June). The fallow period between maize harvest and the next soybean sowing allows Sumatran fleabane to emerge and grow. On the other side, fallow is a suitable moment for Sumatran fleabane control because plants are more susceptible to herbicide in initial stages of growth. In this study, the aim was to evaluate the effectiveness on combined burndown + residual herbicide treatments to control Sumatran fleabane during fallow, after maize harvest. Two experiments were carried out in Campina da Lagoa (PR) and Floresta (PR) and treatments consisted of combinations of herbicides to provide control of emerged plants of Sumatran fleabane (glyphosate + 2,4-D, MSMA and glufosinate), applied isolated or in tank mixes with residual herbicides (metsulfuron, chlorimuron, diclosulam, imazethapyr, imazaquin, flumioxazin, metribuzin, amicarbazone and isoxaflutole) which were expected to prevent the emergence and growth of new weed fluxes. At the time of herbicides application, Sumatran fleabane plants were no taller than 12 cm. Assessments on both efficacy and residual control were performed until soybean crop sowing (45 days after treatment). Glyphosate + 2,4-D mixture was efficient for burndown of Sumatran fleabane. For fallow periods of 45 days, all glyphosate + 2,4-D mixtures with residual herbicides were efficient for Sumatran fleabane control, providing less than 10 plants m-2 and a maximum plant height of 16 cm at soybean sowing date. [ABSTRACT FROM AUTHOR]

The herbicide fomesafen is one of the few broadleaf herbicides for the post-emergence application in common bean. However, this application can cause phytointoxication to this crop, therefore the objective was to evaluate the application of the fungicide pyraclostrobin for reducing herbicide phytotoxification in common bean. The experimental design was a randomized block design, with ten treatments and four replicates. The treatments resulted from the combination of isolated or associated applications of fomesafen and pyraclostrobin at different stages of common bean development (V2, V3 and V4). We evaluated herbicide phytotoxicity, photosynthetic rate, weight of pods per plant, weight of 1,000 grams and grain yield. The injuries caused by fomesafen were low. The treatments did not affect both the photosynthetic rates and the yield components of bean. In general, the treatments that pyraclostrobin were applied had higher production. The application of pyraclostrobin favored the selectivity of herbicide fomesafen to common bean cultivar IPR Tangará. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Ciencias Agroveterinarias is the property of Revista de Ciencias Agroveterinarias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Two experiments were conducted in order to evaluate the influence of straws of different cultures subjected to two methods of irrigation in suppressing the development of weeds Ipomoea triloba and Euphorbia heterophylla. The tests were conducted on the campus of the Integrated College of Campo Mourão - PR during the months of September and October 2014. The treatments were arranged in a factorial design 2x6, the first factor was represented by two irrigation methods, which are superficial and subsurface and the second for five types of straw (sunflower, turnip, oats, beans and wheat) and a control without the presence of straw. Plant number evaluations were performed and number of leaves of I. triloba and E. heterophylla at 7, 14, 21, and 28 DAA, and in the last evaluation collecting area of the plant to obtain the dry weight was carried out. Overall, it was found that the turnip, oats, beans, and wheat, when they receive surface irrigation, promote smaller development of morningglory plants and lower dry mass accumulation of poinsettia plants. [ABSTRACT FROM AUTHOR]

Copyright of Comunicata Scientiae is the property of Comunicata Scientiae and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Agricultural Sciences / Revista Brasileira de Ciências Agrárias is the property of Universidade Federal Rural de Pernambuco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Despite glyphosate-based herbicides are widely used in agriculture, forestry and gardens, little is known about its effects on non-target organisms. The present work evaluated the ecotoxicity of four formulated products (Roundup ® Original, Trop ® , Zapp ® Qi 620 and Crucial ® ) on soil invertebrates. Screening ecotoxicity tests were carried out with soil and oat straw collected in a field experiment, besides laboratory-spiked soils. Screening tests included avoidance behaviour of earthworms ( Eisenia andrei ), collembolans ( Folsomia candida ) and isopods ( Porcellio dilatatus ) in single and multispecies tests; reproduction of collembolans ( F. candida ), and bait lamina in field. Non-avoidance behaviour was observed in standard tests (earthworms) in soil, neither in multispecies tests (earthworm + isopods) using oat straw, while for collembolans it occurred for the product Zapp ® Qi 620 even at the recommended dose. Reproduction of F. candida was not impaired even at high doses in laboratory-spiked soils. Feeding activity on bait lamina test was impaired in treatment corresponding to the red label product, Crucial ® . Results showed the relevance of bait lamina test on screening the impact of herbicides in the field. The findings highlight the importance of considering different formulations for the same active ingredient in risk assessment of pesticides. [ABSTRACT FROM AUTHOR]