Abstract:
Tomato ( Lycopersicon esculentum Mill.) seeds
were germinated in Petri dishes for 7-10 days.
Seedlings were transferred to pots, grown in
greenhouse and Cadmium (Cd) treatments
were applied at concentrations of 0.0, 10.0,
50.0, 70.0 and 100.0 µM for two weeks.
Genomic DNA from tomato leaves was used
for RAPD analysis using four random primers
(OPB05, OPB07, OPB08, and OPB09). RAPD
profiles showed great variations in banding
patterns, particularly in intensity, number,
thickness and mobility of the PCR generated
fragments. Appearance of new RAPD markers
may occur because some oligonucleotide
priming sites could become accessible to
primers due to changes in DNA sequence.
Disappearance of some DNA fragments might
be due to structural rearrangement in DNA
caused by different types of DNA damage
after exposure to cadmium pollution whi ch
can change the number of binding sites of
Taq polymerase. Structural rearrangements
may also result in an increase in the intensity
and thickness of some DNA fragments. The
change in the mobility of DNA fragments
might be the result of single strand
conformational polymorphism (SSCP) that
reveals differences in electrophoretic mobility
between normal and mutant single strands of
DNA. These results indicated that the
genomic DNA template stability was affected
by cadmium pollution. In other words,
cadmium pollution can cause genotoxic
effects on tomato plants that may be regarded
as a bioindicator of environmental pollution.
