The use of pre-emergent herbicides offers a promising alternative for proper management of difficult-to-control weed species in soybeans, such as white-eye (Richardia brasiliensis Gomes), a glyphosate-tolerant species, and weeds in the Amaranthus genus (commonly referred to as pigweeds). Here, we aimed at determining whether weed control efficacy and crop selectivity are altered when pre-emergent herbicide applications take place either prior to, or right after crop sowing. To this end, field trials were conducted employing 10 preemergent herbicide treatments (plus an […]

The occurrence of Cyperus difformis L. biotypes with characteristics of resistance to herbicide application in the rice sector is a worldwide concern. In this sense, the objective was to evaluate the efficiency of the control of C. difformis by acetolactate synthase (ALS) inhibitors and auxin mimic. The experimental design was completely randomized, with four replications, totaling 252 experimental units composed of pots with 12 kilograms of soil and the treatments arranged in a 3x7x2x2 factorial scheme: three herbicides (two ALS […]

The good establishment of agricultural crops depends on several factors related to the way weeds are managed. Morning glory (Ipomoea sp.) Is one of the most problematic weeds in agricultural crops in Brazil, causing a reduction in production and making harvesting operations more difficult. In this sense, the objective was to evaluate the effectiveness of different herbicides applied in post-emergence of viola string. The experiment was conducted from July to September 2018 in a greenhouse. The experimental design used was […]

In the soybean crop, weed resistant to glyphosate, such as horseweed and ryegrass, are difficult to control, making it necessary to associate other herbicides with different mechanisms of action. The objective of the study was to evaluate the influence of the association of herbicides to control glyphosate resistant weed in the soybean pre-planting desiccation and crop development and yield. The experiment was carried out in the 2018/2019 crop year, in an agricultural area that spent the winter fallow. The experiment […]

Tank mixing between herbicides and foliar fertilizers can promote adverse effects on crops due to antagonism between products. Thus, the objective of this study was to evaluate the effects of the application of molybdenum (Mo) in a tank mixture with herbicides on cowpea crop yield and weed control. The randomized block design was adoted, with four replications in a 6×2 factorial scheme. The first factor consisted of the control with weeding and control without weeding and the application of the […]

For decision making on which strategy is improve for weed management, statistical tools such as multivariate analysis. Especially with a large amount of data, can be used. The objective of this study was to evaluate the feasibility of the use of multivariate analysis for studies on the selection of weed flora as a result of the application of different herbicides. The experiment was in field, in randomized blocks, with four repetition, the area was divided into 32 plots with 3 […]

This work was conducted with the objective of evaluating alternatives for chemical control of soybean and cotton volunteer plants, comparing glyphosate-resistant commercial cultivars to new transgenic cultivars resistant to dicamba, in two growth stages. Four independent trials were designed in the greenhouse, repeated for two consecutive years. Infestation of cotton and soybean volunteer plants was simulated in plastic pots with two distinct genetic materials. For cotton, a glyphosate-resistant (Roundup Ready Flex®) and a dicamba and glufosinate-ammonium tolerant (DGT) cultivars were […]

Integrated weed management practices to control fleabane (Conyza spp.) have been essential in integrated crop production systems, such as corn (Zea mays) associated with Congo signal grass (Uruchloa ruziziensis). The objectives of these studies were to evaluate the efficacy of Congo signal grass covering on fleabane suppression and to evaluate different chemical control options to control fleabane during the production of Congo signal grass. The first experiment was conducted after the corn harvest integrated with Congo signal grass by evaluating […]

The continuous use of glyphosate in soybean has led to the appearance of resistant weeds. Thus, alternatives to manage resistant plants are needed, such as the use of products with different mechanisms of action. In this study, the efficacy of the post-emergence application of herbicides with different mechanisms of action in the control of weeds in soybean crop was tested. The experiment was conducted in the 2016/2017 season, in Cambé-PR, using randomized blocks, with four replications. We evaluated the following […]

The selection of Spermacoceae densiflora specie has been verified in areas with the continuous use of glyphosate herbicide. The objective of this work was to evaluate the effect of glyphosate-isolated or associated with herbicides applied in post-emergence of S. densiflora in seed and sprouting plants at different phenological stages. In both cases, a completely randomized design with 5 replications in a 2 x 17 + 1 factorial scheme was used, being two weed phenological stages (4 and 8 fully expanded […]