ALTERNATIVAS DE CONTROLE QUÍMICO CONVENCIONAIS AINDA SÃO EFICAZES PARA O CAPIM AMARGOSO (Digitaria insularis)?

Abstract

Considering the importance of weed management as well as a research of Amargosograss (Digitria insularis) for Brazilian agriculture, this work was developed with the objective of verifying if the herbicide options for the control of Amargosograss are still efficient, due to the history of reports of reductions in the efficiency of control strategies over time, taking into account cost-effectiveness and future management perspectives. For this, an experiment was carried out in a greenhouse, with Capim-amargoso plants cultivated in pots. The design used was completely randomized, with six treatments Clethodim (0.5L / ha) + Glyphosate Potassium (2L / ha); Ethyl Quizalofop P (0.5L / ha) + Potassium Glyphosate (2L / ha); Clethodim (0.5L / ha) + Ethyl Quizalofop P (0.5L / ha) + Potassium Glyphosate (2L / ha); Clethodim-Oxime + Methyl Haloxyfop P (1.5L/ha); Cyclohexanedione + Haloxyfop P Methyl (1.0 L / ha) + Glyphosate Potassium (2L / ha) and control without herbicide application. The treatments were applied when bittergrass plants were in full reproductive stage, perennial, 40 days after planting. After the application of herbicides, control scores were assigned at 7, 14, 21 and 28 days. After 28 DAA, the plants were cut and the pots were potted under controlled periodic irrigation, in order to verify the regrowth capacity of the bittergrass plants up to 90 days after cutting (DAC). Green mass, dry mass and cost analysis were analyzed. All treatments were effective 28 days after application, with a control system greater than 80%. The treatment with Kennox provided 96% of control, at a cost of R$ 165.00 per hectare. With the exception of the T06 treatment, which had regrowth, the other conventional treatments for the control of amargoso grass in this study were still effective.