The intensified use of glyphosate in Cerrado areas has caused several socio environmental damages. The use of this herbicide can result in drift to areas adjacent to
crops, affecting non-target communities. The objective of this study was to analyze the
physiological and morphoanatomical effects on Hymenaea courbaril Lindl (Fabaceae)
(jatobá-da-mata) exposed to glyphosate, providing subsidies for the use of the species
in the field, in order to indicate possible bioindicative characteristics of the presence of
this herbicide. Seedlings were produced from seeds and acclimated in a nursery. The
experiment consisted of 8 treatments, with 4 repetitions each, including 7 different doses
of glyphosate: 25, 50, 100, 200, 400, 800, 1200 g a.i. ha-1 and the control (0g).
Physiological analyzes were performed on the same leaflets of the leaves evaluated for:
concentration of chloroplast pigments, evaluation of membrane permeability and
morphoanatomical analyzes. The H. courbaril seedlings tended to decrease the values
of physiological parameters in A, Gs, E, EUA and EiC, and an increase in Ci and Ci/Ca
indicating an increase in the concentration of CO2 in the leaf mesophyll. Glyphosate did
not cause significant damage to the content of chloroplast pigments or to membrane
degradation. Visible damages were found 5 DAA from the dose 50g i.a ha-1, indicating
leaf chlorosis, and at 9 DAA, the buds of the apical meristem were necrotic in these
plants. These effects were more pronounced in plants exposed to 1200g a.i. ha-1.
There was a significant reduction in the thickness of the abaxial epidermis in plants
exposed to a higher dose of glyphosate. Anatomical changes were observed in the
plant's mesophyll, among which the membrane retraction, change in the shape of the
chloroplasts and the increase of intercellular spaces are highlighted. Thus, Hymenaea
courbaril presented parameters that can be used as bioindicator characters to assist in
the monitoring of glyphosate drift, in non-target plants, present in the Cerrado plant
fragments.
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