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Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental 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 aim of this study was to evaluate the role of rock powder in the phytoremediation of Inceptisol (sandy loam) and Oxisol (clay) contaminated with diuron. Canavalia ensiformis plants were grown in pots containing 7.5 kg of both soils, with doses of 0, 4, and 8 t ha−1 of rock powder. Diuron was applied in doses ranging from 875 to 3500 g of a.i. ha−1. The injury level was assessed at 42 days after emergence (DAE), and the morphological characteristics were assessed at 120 DAE. After phytoremediation, the soil was analyzed using High Performance Liquid Chromatography (HPLC) and by bioassay with cucumber (Cucumis sativus) to detect diuron. In Oxisol, no injury was observed, and the rock powder (4 t ha−1) benefited the growth of C. ensiformis regardless of the dose of diuron. In Inceptisol, the greatest reduction in growth occurred with 3500 g a.i. ha−1 of diuron and 8 t ha−1 of rock powder. Diuron was detected after 120 days in Inceptisol with 2625 g a.i. ha−1 without rock powder and 3500 g a.i. ha−1 with and without rock powder. The cucumber bioindicator in Inceptisol showed an increase in the level of injury as the dose of diuron increased. The rock powder favored the growth of C. ensiformis and was able to phytoremediate high concentrations of diuron, which supports the safe use of this herbicide for weed control, minimizing environmental impacts. [ABSTRACT FROM AUTHOR]

Shading interferes with the weed's biology, which can change their sensitivity to post-emergence herbicides. The objective was to evaluate the control of Merremia cissoides with glyphosate in full sunlight and shade conditions in two plant growth stages (30 and 73 days after sowing (DAS)). At 30 and 73 DAS, treatments were established in a 2 × 5 and 2 × 6 factorial scheme, respectively. In both experiments, the growth environments constituted the first factor, and the glyphosate doses the second factor. Shading promoted 50 and 40% reductions in glyphosate doses at 30 and 73 DAS, respectively. At 73 DAS, M. cissoides is 177.77 and 131.48% more tolerant to glyphosate than 30 DAS in shading and full sunlight, respectively. Due to the increase in glyphosate tolerance as the plant grows, the management of M. cissoides should be carried out until the stage of six fully expanded leaves. Increasing glyphosate doses reduced the quantum yield of photosystem II and electron transport rate (ETR) in both growth environments, with ETR data showing a high negative correlation with the control. The doses reductions promoted by shading and glyphosate application in the initial growth stage of M. cissoides reduces costs and the negative environmental impacts of this herbicide use. [ABSTRACT FROM AUTHOR]

Copyright of Revista Agrotecnologia is the property of Universidade Estadual de Goias 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.)