Open Access
ARTICLE
2,4-D Hyper Accumulation Induced Cellular Responses of Azolla pinnata R. Br. to Sustain Herbicidal Stress
Arnab Kumar De, Arijit Ghosh, Debabrata Dolui, Indraneel Saha, Malay Kumar Adak*
Plant Physiology and Plant Molecular Biology Research Unit, Department of Botany, University of Kalyani, West Bengal, India
* Corresponding Author: Malay Kumar Adak. Email:
Phyton-International Journal of Experimental Botany 2020, 89(4), 999-1017. https://doi.org/10.32604/phyton.2020.010828
Received 31 March 2020; Accepted 25 May 2020; Issue published 09 November 2020
Abstract
In the present experiment with ongoing concentration (0 µM, 100 µM,
250 µM, 500 µM and 1000 µM) of 2,4-D, the responses of
Azolla pinnata R.Br.
was evaluated based on cellular functions. Initially, plants were significantly tolerated
up to 1000 µM of 2,4-D with its survival. This was accompanied by a steady decline
of indole acetic acid (IAA) concentration in tissues with 78.8% over the control.
Membrane bound H
+
-ATPase activity was over expressed within a range of 1.14
to 1.25 folds with activator (KCl) and decreased within a range of 57.3 to 74.6%
in response to inhibitor (Vanadate) application. With regards to IAA metabolism,
plants recorded a linear increase with wall bound oxidase activity up to maximum
concentration of 2,4-D. The variations were more moderated when wall bound
IAA-oxidase recorded a linear increase proportionate to the 2,4-D concentrations.
This was more extended with the presence of different isoforms of IAA-oxidase
which was much more pronounced with distinct polymorphisms of expressed proteins, however, not independent to the 2,4-D concentrations. Polyamines like spermine, spermidine and putrescine (spm, spd and put) were not consistent in
concentration with the dosages of 2,4-D. Besides these, plants were induced to apoplastic NAD(P)H oxidase activity maximally by 1.6 folds under 500 µM 2,4-D over
control. Still, putrescine responded more or less consistently and recorded maximally
11.9 folds at 500 µM 2,4-D as compared to the control. NAD(P)H oxidase activity
recorded maximally 1.6 folds against control and remain consistent throughout the
concentrations of 2,4-D. GPX along with APX were more linear in responses
through the concentration of 2,4-D except CAT as compared to control. On enzymatic antioxidative activity, peroxidases (GPX and APX) were overexpresed in a
similar manner except for catalase with a non-significant rise. In stabilization of cellular redox, glutathione reductase attended maximum value by 2.45 folds at 1000 µM
evidenced with significant variations in protein polymorphism. The sensitivity of 2,4-
D also appeared in
Azolla with a maximum loss of nucleic acids as documented by
the comet assay. Moreover, the
Azolla might have some DNA damage protective
activity as evident using frond extract with plasmid nick assay. Therefore,
Azolla
plants with its cellular responses is evident to sustain against the 2,4-D herbicidal
stress and may be granted in bio remediation process for the contaminated soil.
Keywords
Cite This Article
De, A. K., Ghosh, A., Dolui, D., Saha, I., Adak, M. K. (2020). 2,4-D Hyper Accumulation Induced Cellular Responses of
Azolla pinnata R. Br. to Sustain Herbicidal Stress.
Phyton-International Journal of Experimental Botany, 89(4), 999–1017. https://doi.org/10.32604/phyton.2020.010828