RESPOSTAS MORFOFISIOLÓGICAS in vitro DE
Alternanthera tenella Colla (Amaranthaceae)
FRENTE AO ESTRESSE INDUZIDO PELO CÁDMIO E
AÇÃO ATENUANTE DO SILÍCIO
Name: FRANCIELE PEREIRA ROSSINI
Publication date: 26/04/2021
Advisor:
Name |
Role |
|---|---|
| ANDREIA BARCELOS PASSOS LIMA GONTIJO | Advisor * |
Examining board:
| Name |
Role |
|---|---|
| ANDREIA BARCELOS PASSOS LIMA GONTIJO | Advisor * |
Summary: Rossini Franciele Pereira; M.Sc .; Federal University of Espirito Santo; April 2021;
Morphophysiological responses in vitro Alternanthera tenella Colla
(Amaranthaceae) compared to the stress induced by cadmium and silicon
mitigating action; Advisor: Profa and Dra. Andreia Barcelos Passos Lima Gontijo;
Co-advisor: Dr. João Paulo Rodrigues Martins and Prof. Dr Antelmo Falqueto.
Among the techniques used to decrease the level of heavy metal contamination in the
soil is the use of phytoremediation plant species. Although the ability to bioaccumulate
heavy metals, such as Cd in the aerial part, is ensured, many plants have
morphophysiological disorders that can reduce their use as phytoremediation due to
changes in the accumulation of biomass. Thus, the understanding of the relationships
between plant and heavy metals, as well as the interaction of these two factors with
stress-mitigating elements such as silicon (Si), are fundamental for the recovery of
ecosystems. Thus, this study aimed to analyze the anatomical and physiological
modulations induced by the synergy between Cd and Si in A. tenella plants, in addition
to elucidating whether Si can mitigate the deleterious effects induced by Cd. The
environmental cultivation conditions chosen for this work was in vitro. Nodal segments
of A. tenella were grown in MS medium supplemented with a gradient of Cd
concentration (0, 50, 100 or 200 μM) combined with two levels of Si (0 and 40 μM),
constituting eight treatments. After 34 days, leaf anatomy, pigment content, chlorophyll
a fluorescence, growth characteristics and tolerance index were analyzed. The
existence of interaction between Si and Cd during the in vitro cultivation of A. tenella
was clearly proven. The addition of Si in the culture medium resulted in a better
anatomical and photosynthetic joint, improving the growth rate and decreasing the
level of physiological stress and successively increasing the Cd tolerance index,
especially at the highest concentrations of this element. It is concluded that the synergy
exists between these two elements, improving the capacity of bioaccumulation and,
consequently, the remediation of this metal by this species.
Keywords: heavy metal, phytoremediation, plant anatomy, plant physiology,
beneficial element.
