ATIVIDADE RESIDUAL DE HERBICIDAS SOBRE ESPÉCIES BIOINDICADORAS

Abstract

The persistence of herbicides in the environment depends on factors such as soil properties and biological parameters that regulate microbial degradation rates. Knowledge of the residual effects of herbicides in different soils is essential to determine safe applications in sensitive crops, avoiding environmental problems and weed control, using the appropriate dosage for each soil. This study aimed to evaluate plant species that are bioindicators of the residual activity of the herbicides flumioxazina, trifluralin and diclosulam in sandy and clayey soils sown with lettuce and cucumber seeds. For this, two experiments were carried out in a greenhouse, evaluating two bioindicator species: Lactuca sativa (lettuce) and Cucumis sativus (cucumber), under a completely randomized experimental design, with 3 (herbicides x 2 (soil texture) , with four replications, in addition to a treatment without the addition of herbicides (control). Recommended doses of Flumioxazina, Trifluralin and Diclosulam were used in soils with clayey and sandy texture. Plant height (AP), dry mass of part (MSPA) and phytotoxicity of the species. The application of the herbicides diclosulam and flumioxazina in both types of soil caused a reduction in height, dry mass production and promoted greater phytotoxicity in the species Lactuca sativa and Cucumis sativus. The application of the herbicide trifluralin provided an increase in the height of the species and dry mass production for both species, both for clayey and sandy soils. with greater responses in clayey soil.