The growth index of the explant increased significantly when
the strength of POME media was reduced by half of its initial value
(P < 0.05). This could be due to the decrease in concentration of
toxic materials in POME media, which had reduced the inhibitory
effect on plant growth as compared to full strength POME media. In
addition, the nutrients presented in half strength POME media
were capable of sustaining the survival and growth of the explants.
However, as the strength of POME media were reduced to a quarter
of its initial value, the growth index of explant after
fifteen days had
the same effect as those in 1/2 POME media (P > 0.05). When the
POME medium was further diluted to one eighth of its initial
strength, the growth index of the explant decreased accordingly.
This might be due to insufficient nutrients such as ammonia,
nitrate and phosphate in POME media to sustain photosynthesis
process for the growth of the explants as shown in Table 3.
The root formation had been observed in POME media, but not
in MS media. This might be due to the low nutrient level as
reported in POME characterization as compared to those in control
medium (MS medium) which served as the driving force for the
development of roots. The growth of the explant was restricted and
retarded because the nutrients in POME media were used up for
the development of roots. The development of roots in 1/8 strength
POME media was maximum followed by 1/4 POME media, 1/
2 POME media and minimum at full strength POME media. This
might be due to the inhibition effect caused by high concentration
of toxic phenolic substances as compared to other growth media