Ameliorative Approaches for Management of Chromium Phytotoxicity: Current Promises and Future Directions - Applied Environmental Biotechnology: Present Scenario and Future Trends - page 89

ing agents can also cause groundwater pollution
by uncontrolled metal dissolution and leaching.
Therefore, the risk assessment must be carried out
thoroughly in the use of EDTA or other chelators
for phytoextraction before taking further steps
towards development and commercialization of
this remediation technology. There is a need for
further experimental validation of such promises
under different soil and environmental conditions
with major crops. Further, complications due to
soil and water contamination by multiple heavy
metals demands integrative approaches and tri-
als to get conclusive results. This would lead to
development of more generalized and effective
strategies for amelioration of phytotoxic effects.
Another important aspect that must be considered
during the study of any approach is “maintenance
of natural beneficial microbial population” under
such experimental conditions. This would be im-
portant in case of bioremediation using microbial
inoculants. There are no doubts about symbiotic
and beneficial relationship between plants and
microbes. Therefore, use of microbes with dual
characteristics of Cr tolerance and plant growth
promotion will be of high significance for ame-
lioration as well as increased crop productivity
for increased population. Apart from bioreme-
diation and metal chelation, PGRs are also being
studied extensively for amelioration of differ-
ent heavy metals, and SA has been shown to be
highly effective in several such studies. BRs are
again of high importance considering the sup-
porting relevant studies for Cr. Integrative use
of such growth regulators and inclusion of major
crops under further experiments with multifield
and multisite trials will lead to development of
consensus among outcomes and final recommen-
dations. Again, combined effect of heavy metals
and their effective amelioration will require in-
depth research on molecular mechanisms behind
such effects. Current research trends toward un-
derstanding of key genes under different abiotic
stresses and transcriptomics studies would be a
benchmark for development of these strategies.
The actual success of any of the above strategies
will be governed by a thorough understanding of
the molecular basis of their action by extensive

research, its cost effectiveness, user-friendliness,
and environmental impact of course.

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