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The aims of this study were to evaluate the effectiveness of diquat, copper hydroxide, copper oxychloride and their associations diquat + 0.1% copper oxychloride and diquat + 0.1% copper hydroxide to control Cerathophyllum demersum. Therefore, the concentrations used were 0.1, 0.3, 0.5, 0.7, 1.0 and 1.5 mg L-1 oxychloride and copper hydroxide and 0.2, 0.4, 0.8 and 1.2 mg L-1 diquat and their associations with 0.1% copper oxychloride and 0.1% copper and a control hydroxide. The experimental design was completely randomized with ten replications for 45 days. For evaluation we used a scale of 0-100% control of notes and rated the weight (g) and length (cm) of pointers at the end of the trial period. Diquat showed 100% efficacy at 30 DAA, associations in 21 DAA and copper sources promoted regrowth of C. demersum. Diquat and its associations were more effective in controlling C. demersum. The use of herbicide in combination with a copper source is more efficient for the control of submerged weeds because it potentiates the effect of the herbicide in weed control O objetivo deste estudo foi avaliar a eficácia do diquat, hidróxido de cobre, oxicloreto de cobre e suas associações (diquat + 0,1% de oxicloreto de cobre e diquat + 0,1% de hidróxido de cobre) para o controle de Cerathophyllum demersum em condições de laboratório. Para isso, foram utilizadas as concentrações de 0,1, 0,3, 0,5, 0,7, 1,0 e 1,5 mg L-1 do oxicloreto e hidróxido de cobre e de 0,2, 0,4, 0,8 e 1,2 mg L-1 do diquat e suas associações com 0,1% de oxicloreto de cobre e 0,1% de hidróxido de cobre e um controle. O delineamento experimental utilizado foi o inteiramente casualizado com dez repetições, ao longo de 45 dias de avaliação. Na avaliação foi empregada uma escala de notas de controle (0-100%) e avaliado o peso (g) e o comprimento (cm) dos ponteiros ao final do período experimental. O diquat apresentou 100% de eficácia aos 30 DAA, e as associações em 21 DAA; as fontes de cobre promoveram a rebrota de C. demersum. O diquat e suas associações foram mais eficazes no controle de C. demersum. A utilização de herbicida em associação com uma fonte de cobre é mais eficiente para controle de macrófitas submersas, pois potencializa o efeito do herbicida no controle das plantas.

the aims of this study were to determine imazapyr efficacy for floating macrophyte control and ecotoxicology for non-target organisms. For the floating macrophyte control efficacy tests were used the doses of 0,5; 1,0; 2,0; 2,5; 3,0; 3,5 and 4,0 L ha-1 and a control with 10 replicates. The acute toxicology for non-target organisms was estimated by lethal concentration 50% (LC50 and EC50). The floating macrophyte control efficacy was over 90%. Imazapyr was classified as moderately toxic for the following biomarkers: L. minor, H. eques, B. rerio, P. caudimaculatus, P. canaliculata, and P. mesopotamicus and lightly toxic for A. caroliniana. Thus, imazapyr herbicide is a tool with great potential to be used on floating macrophyte control (E. crassipes, P. stratiotes e S. molesta) in Brazil and this practice can be evaluated by the use of application biomarkers. O objetivo deste estudo foi determinar a eficácia do imazapyr no controle de macrófitas flutuantes e a ecotoxicidade para organismos não alvos. Para os ensaios de eficácia de controle das macrófitas flutuantes, foram utilizadas as doses de 0,5; 1,0; 2,0; 2,5; 3,0; 3,5 e 4,0 L ha-1 e um controle com 10 réplicas. A toxicidade aguda para organismos não alvos foi estimada pela concentração letal de 50% (CL50 e CE50). A eficácia de controle para as macrófitas flutuantes foi acima de 90%. O imazapyr foi classificado como moderadamente tóxico para os bioindicadores L. minor, H. eques, B. rerio, P. caudimaculatus, P. canaliculata e P.mesopotamicus e ligeiramente tóxico para A. caroliniana. Assim, o herbicida imazapyr é uma ferramenta com grande potencial para ser usada no controle de macrófitas flutuantes (E. crassipes, P. stratiotes e S. molesta) no Brasil, e a sua utilização pode ser avaliada por meio de bioindicadores de aplicação.

Made available in DSpace on 2018-12-11T17:26:00Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-01-01. Added 1 bitstream(s) on 2019-10-09T18:32:13Z : No. of bitstreams: 1 S0100-83582015000300433.pdf: 289008 bytes, checksum: 98ba8171591116b5c4264d342be4e730 (MD5) The objective of this study was to evaluate the consumption potential, food preference and use of snail Pomacea canaliculata as a biocontrol agent of four submerged aquatic macrophytes (Ceratophyllum demersum, Egeria densa, Egeria najas and Hydrilla verticillata). Two experiments were performed. In the first experiment, the introduction of a snail took place and 10 grams of each macrophyte in plastic containers with 1 liter of water. The assessments of consumption by the snail were performed at each 48 hours, during 12 days. The second experiment was performed in 600 liters microcosms containing five snails in each experimental unit. Fifty grams of each macrophyte were offered the snails at the same time, adding the same amounts after seven, 14, 21 and 30 days. On both trials, the most consumed macrophyte by the P. canaliculata was H. verticillata (7.64 ± 1.0 g 48 h and 50 ± 0.18 g) respectively, significantly differing from the others. However, in the absence of H. verticilata, E. najas and E. densa were consumed. The preference of P. canaliculata for H. verticillata is very interesting, because this plant is exotic and problematic in Brazil, and the snail is one more tool for biological management of submerged aquatic macrophyte H. verticillata. UNIFEB NEPEAM/FCAV/UNESP NEPEAM/FCAV/UNESP

Made available in DSpace on 2018-12-11T17:25:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-01-01. Added 1 bitstream(s) on 2019-10-09T18:32:08Z : No. of bitstreams: 1 S0100-83582015000200241.pdf: 1153865 bytes, checksum: 00dafa23697d634a04f9cc34275b1df5 (MD5) The aim of this study was to assess the effectiveness of glyphosate, as Rodeo® formulation, to control Eichhornia crassipes, Pistia stratiotes, Salvinia molesta, Salvinia herzogii and Urochloa subquadripara, under greenhouse conditions. The doses assessed were (480, 960, 1440, 1920, 2400, 2880, 3360 and 3840 g ha-1 of glyphosate) with 0.5% of the Aterbane® BR surfactant and a control, with no herbicide application. All experiments were conducted in a completely randomized experimental design with ten replications. Applications were carried out by precision backpack sprayer at a CO2 constant pressure of 25 psi and spray solution consumption of 200 L ha-1. Product effectiveness was determined by assessing the growth inhibitions and phytotoxicity signals during the periods of 3, 7, 15, 21, 30 and 45 days after application (DAA). At 45 DAA, the highest glyphosate dose (3840 g ha-1) displayed 100% effectiveness for all four macrophyte species. Under greenhouse conditions, the glyphosate in formulation Rodeo® with 0.5% of Aterbarne® BR surfactant showed excellent effectiveness, inhibiting the growth of the floating aquatic macrophytes. This procedure can be included on the tillage plans for these species. Centro Universitário da Fundação Educacional de Barretos, UNIFEB Núcleo de Estudos e Pesquisas Ambientais em Matologia, UNESP UNESP Núcleo de Estudos e Pesquisas Ambientais em Matologia, UNESP UNESP