The agricultural advance over the Cerrado has caused countless environmental
issues. The native vegetation has been replaced by large monocultures which make
intensive use of pesticides. These chemical substances cause undesirable changes
in ecosystems, highlighting the contamination of non target native forest species,
through drift. Among the various fruit species of the Cerrado, Eugenia dysenterica
DC, popularly known as cagaita, excels for its multiple use by local communities. Due
to the deleterious potential of pesticides on human health and the environment, it is
essential to seek mechanisms to monitor environmental conditions. Thus, the
objective of this study was to evaluate the effects of glyphosate and fipronil on
Eugenia dysenterica DC. and its potential usage as a bioindicator of the presence of
these substances in the environment. The experiments was conducted in the
greenhouse of the Universidade Federal do Tocantins - UFT, Palmas campus, and
the visual toxicity, physiological and morphoanatomical characteristics of E.
dysenterica were analyzed, exposing it to concentrations of 0, 550, 1110 and 2220
g.e.a.ha-1 of glyphosate and 0, 260, 520 and 1040 g.i.a.ha-1 of fipronil, respectively.
The results indicate that glyphosate caused toxicity in leaves in all treatments.
Gradual reductions in photosynthesis (A), stomatal conductance (gs) and
transpiration (E), in response to increasing doses, over the course of days, were also
identified. Glyphosate caused damage to the anatomical structures of E. dysenterica
leaves in all doses. Regarding fipronil, the individuals presented symptoms toxicity at
the highest dose and decrease in photosynthetic, stomatal conductance, and
transpiration that varied as a function of dose and exposure time. Anatomical
changes were also identified in the tissues in all treatments. Given the data analyzed,
it can be stated that E. dysenterica plants are sensitive to the action of glyphosate
and fipronil. Negative effects of these agrochemicals were identified in morphological,
physiological and anatomical parameters that were strengthened by the dose and
exposure time. However, we emphasize the need for more detailed research,
seeking to ratify in the field the effectiveness of the bioindicator parameters identified
in this research.
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