Glycerine associated molecules with herbicide for controlling Adenocalymma peregrinum in cultivated pastures

Abstract

The weed Adenocalymma peregrinum that is popularly known in Brazil as “ciganinha”, belongs to the family Bignoniaceae. The only way to control this plant species in crop fields is by the application of herbicides on the stump or directly on the stem. The present study aimed to analyze the effect of glycerine in controlling A. peregrinum (MIERS) L.G.Lohmann when applied on the stem. The glycerin used as a spray application of herbicide, underwent pre-purification processes with different concentrations of phosphoric acid (85%) and was characterized for water content, sulphated ash, total glycerol, matter organic non-glycerol (MONG), methanol and pH. For the analysis of the chemical composition of the stem lignin, holocellulose, extractives, calorific value and elementary quantitative determination of C, N, H, S were determined, as well as the total content of oxygen from the stem. The field work was installed at the town of Alvorada-TO, following the randomized complete block design with six treatments and four replications. Results show that the stem of A. peregrinum contains a significant amount of nitrogen, compared to other species, and high lignin content which makes it the most resistant species. The use of glycerin combined to the herbicide (picloram and triclopyr), was not efficient when compared to diesel oil. It was observed that the glycerin has potential as a vehicle for applying herbicides, leaving much to the development of new studies to make changes in its physicalchemical characteristics.

Key words: Weeds, pastures, management, Adenocalymma peregrinum.