Abstract:
Turfgrasses are usually important groundcover plant
s in many landscapes. They
occupy the lowest surface of the landscape, close t
o pollutant particles. So, they can be an
attractive option for environmental remediation. To
day, high concentrations of hazardous
chemicals such as lead are among the most serious e
nvironmental problems.
In vitro
selection of turfgrass accumulator or tolerant of t
oxic ions may lead to production of
plants that have better adaption to polluted sites.
This study was undertaken to
investigate the tolerance or accumulation potential
in Bermuda grass to high
concentrations of lead under tissue culture conditi
on and identifying differences at the
molecular level among accumulators by RAPD markers.
Callus that were used for
in vitro
selection were exposed to different concentrations
of lead in the media. After the first
mowing, tolerant plantlets were evaluated for lead
accumulation potential. All plants of
Bermuda grass originating mainly from regeneration
pathways had undergone genetic
changes. The results revealed that occurrence of so
maclonal variation via somatic
embryogenesis and organogenesis of Bermuda grass cu
lture with a frequency of 33%.
Although some
in vitro
derived plants showed increase in uptake potential
of lead in their
shoots (2 times higher Pb extraction), there were s
ome regenerates with decreased lead
accumulation in shoot, and some varieties without a
ny changes in lead uptake properties
in comparison to the control. Molecular marker coul
d be efficient in determining the
genetic changes induced by somaclonal variation. Th
e improvement of lead accumulation
in lead extraction varieties indicated a successful
mutation in Bermuda grass for breeding
traits such as phytoremediation purpose.
Keywords
: Bermuda grass, Lead accumulation, Lead-RAPD.
