Abstract: Background: Eragrostis plana is an invasive plant in native grassland areas associated with degradation of the Pampa biome. Selective control of E. plana is difficult due to its similarity to other grassland species. There is a lack of information about E. plana control using selective herbicide application equipment. Objective: The present study aimed to evaluate the efficacy of a pressurize rope wick applicator for controlling the invasive plant E. plana as function of different salts of glyphosate, application volumes, and year seasons. Methods: The studies were carried out under field conditions and repeated. The first study evaluated glyphosate salts of isopropylamine, dimethylamine, monoammonium, diammonium, and potassium at doses of 720 and 1440 g ha-1 and clethodim at 60 and 120 g ha-1. The second study assessed application volumes of 8, 24, 40, and 56 L ha-1 using isopropylamine and potassium salts of glyphosate. Results: Glyphosate applied in summer was more effective at controlling E. plana, with less regrowth than glyphosate application in winter. The glyphosate diammonium was more effective at controlling E. plana than isopropylamine, dimethylamine, monoammonium, or potassium salt formulations at 1440 g ha-1. Application volume of glyphosate between 8 and 40 L ha-1 provided similar control of E. plana and pasture selectivity. Conclusions: Glyphosate applied with a rope wick selective applicator was effective in controlling E. plana clumps and was selective to grassland. The control efficacy varied as a function of glyphosate salts and year season, but not due to application volume of 8 and 40 L ha-1.

RESUMO O conhecimento específico sobre os padrões de dormência e germinação de plantas daninhas auxilia o desenvolvimento de estratégias integradas de manejo. Objetivou-se avaliar e selecionar métodos eficazes de superação de dormência de sementes da espécie B. latifolia, bem como determinar sua influência no processo germinativo. Foram conduzidos sete ensaios com tratamentos correspondentes: Ensaio 1 - escarificação mecânica, ácido sulfúrico, água quente e água corrente; Ensaio 2 - pré-esfriamento a 4 ºC e calor seco 60 ºC; Ensaio 3 - ácido giberélico nas concentrações de 0; 50; 100; 200 e 400 ppm; Ensaio 4 - ácido acético e nitrato de potássio 2% (3 e 6 h); Ensaio 5 - três associações duplas dos melhores tratamentos dos quatro primeiros ensaios; Ensaio 6 - estratificação em caixa de areia e pré-embebição em papel de germinação e; Ensaio 7 - curva de embebição. Utilizou-se o delineamento inteiramente casualizado, com quatro repetições de 20 sementes. As sementes foram submetidas ao teste de germinação em B.O.D. a 25 ºC e fotoperíodo de 12 h, em caixas de polipropileno transparente. Foram avaliados a porcentagem de germinação, tempo médio de germinação e a frequência relativa de germinação e mensurou-se o peso das sementes após embebição no ensaio 7. Os tratamentos mais eficientes em superar a dormência das sementes foram os de calor seco, ácido giberélico 283 ppm e nitrato de potássio 3 h. As associações de calor seco + nitrato de potássio e nitrato de potássio + ácido giberélico incrementaram em 25% a porcentagem de germinação em relação aos tratamentos isolados.

ABSTRACT Specific knowledge on dormancy and germination patterns of weed species aids the development of integrated management strategies. This study aimed to evaluate and select effective methods for overcoming dormancy in B. latifolia seeds, as well as determining their influence on the germination process. A completely randomized experimental design was used, with four replications and 20 seeds per repetition. Seven tests were conducted, with the corresponding B. latifolia seed treatments: Test 1 - mechanical scarification, sulfuric acid, hot water and running water; Test 2 - pre-cooling at 4 °C and dry heat at 60 °C. Test 3 - gibberellic acid at concentrations of 0, 50, 100, 200 and 400 ppm; Test 4 - acetic acid and potassium nitrate 2%; Test 5 - dual combinations of the three best treatments observed in the first four tests. Test 6 - pre-soaking in a sandbox and in germination paper and; Test 7 - imbibition curve. The seeds were submitted to the germination test in BOD at 25 °C with a photoperiod of 12h, in transparent polypropylene boxes. Germination percentage (GP), mean germination time and relative frequency of germination were determined and the weight of the seeds after soaking in Test 7 was measured. The best treatments for overcoming seed dormancy were dry heat, gibberellic acid 283 ppm and KNO3 3h. The association of dry heat + potassium nitrate 3 h and potassium nitrate 3 h +gibberellic acid increased germination percentage by 25% compared to isolated treatments.