Embryo rescue is a technique in plant tissue culture that
involves the isolation and culture of embryos from hybrid or cross-pollinated
seeds to produce viable plants. This technique is particularly useful for
rescuing embryos that are unable to germinate or develop due to genetic
incompatibilities between the parent plants.
The process of embryo rescue can be divided into several
stages, which include:
- Collection:
The first stage involves the collection of hybrid or cross-pollinated
seeds from the parent plants. These seeds are often sterile or unable to
develop due to genetic incompatibilities between the parent plants.
- Isolation:
The embryos are then isolated from the seeds using aseptic techniques to
prevent contamination. The embryos are removed from the seeds using
forceps or a scalpel and transferred to a suitable culture medium that
contains all the necessary nutrients and growth regulators for their
development.
- Culture:
The embryos are then cultured in vitro under controlled conditions, such
as temperature, light, and humidity. The culture medium is usually
supplemented with plant hormones, such as auxins and cytokinins, to
promote the development of the embryos.
- Development:
The embryos begin to develop into viable plantlets after a period of
culture. This can be achieved by manipulating the growth regulators in the
culture medium, such as increasing the concentration of auxins or reducing
the concentration of cytokinins.
- Regeneration:
The final stage of embryo rescue involves the regeneration of the rescued
plantlets into mature plants. This can be achieved by transferring the
plantlets to a fresh culture medium that contains lower levels of growth
regulators and promoting the formation of shoots and roots. The
regenerated plants can then be transferred to soil and grown into mature
plants.
The benefits of embryo rescue include the ability to produce
viable plants from hybrid or cross-pollinated seeds that are unable to develop
due to genetic incompatibilities between the parent plants. This technique can
also be used for the production of new plant varieties and for the study of
plant genetics. However, embryo rescue can be technically challenging and
requires a high level of expertise in sterile technique and tissue culture. It
can also be time-consuming and expensive, as large numbers of embryos may need
to be rescued to produce a viable plant.