plant tissue culture

2. Heavy metals
 Heavy metals are defined as that causes environmental problems
such as toxicity, stress etc which cannot be biologically degraded.
The most common heavy metal contaminants are Cd, Cr, Cu, Hg, Pb,
and Zn.
 Some of these metals are micronutrients necessary for plant growth,
such as Zn, Cu, Mn, Ni, and Co.
 while others have unknown biological function, such as Cd, Pb, and
Hg.

3.  The HMs are known to induce
 “oxidative stress” in plant cells disrupting plant
metabolism and growth
 Therefore, another important strategy is activation of
“anti-oxidative enzymes” counteracting reactive
oxygen species and thereby minimizing the adverse
impacts of oxidative stress on the plant cells.

5. Plants in tissue culture
Producing plants via tissue culture has several
advantages:
 Plants are genetically identical, as the parent material.
 They can be very site-specific, propagated from parent
plants present on the exact location, if desired.
 Multiplication can be rapid. Plants may be quicker to
mature, flower and set seed.
 Many thousands of plants can be cultured in a very small
space.

6. Remediation of HMs
 There are many proposed strategies for remediation of
soil heavy metal:
 phytoremediation(removal, degradation, of
containment in soils).
 phytoextraction (to reduce soil HM levels).
 phytostabilization (to reduce soil erosion, leaching
and runoff.
 phytovolatilization (uptake by plant roots from soil).

8. Factors affecting in plant tissue culture:
 Plants species are screened, and those with superior
remediation properties are selected.
 Agar is developed to enhance remediation (pH
adjustment, addition of chelators, fertilizers.
 For example, the amount of lead absorbed by plants
is affected by the pH. To reduce lead uptake by plants,
the pH of the soil is adjusted with lime to a level of
6.5 to 7.0

9.  Since the bioavailability of heavy metals in soils
decreases above pH 5.5–6, the use of a chelating agent is
warranted, and may be required, in alkaline soils.
 The Root Zone is of special interest in phytoremediation.
It can absorb contaminants and store or metabolize it
inside the plant tissue.