Control-pollination is a technique used in plant improvement to
produce progeny that receive genes from each of two known parent
plants. Control-pollination consists of transferring pollen from one
plant to the receptive female reproductive organs of another plant
while excluding all other pollen.
Control-pollination is necessary to:
- establish and maintain a pedigreed breeding population.
- control inbreeding in the breeding population and
- hybridize and back-cross among species.
Control-pollination techniques are specially designed and managed
to produce seed with greater genetic trait and more genetic
uniformity than spontaneously-pollinated plants and also eliminate
pollen contamination problems
To cross-make a controlled pollination of a flower and to make
sure it sets fruit hand-pollination is usually required, just use a
male flower like a paintbrush, and paint the stigma with pollen.
(How to hand-pollinate depends on the flower. Some are simple, some
are not. Depending on flower’ structure that may vary a lot in
different species).
In
self-fertile species it is also necessary
emasculation
of the flowers, while for
self-sterile
species you do not need to worry about self-contamination, therefore
no emasculation is necessary.
Hand-pollination also requires pollen to be available when the
flower is ready to be pollinated. That's not always easy, it may be
necessary collect pollen and store the pollen in advance.
Bagging is a fundamental requirement and of all the pollinating
operations. The female (receptive) flowers must be covered before
the anthesis in order to protect the stigma from being contaminated,
until the desired pollen can be applied. The bag used is usually
made of semi-transparent treated paper .The flowers may be covered
by placing the bag over the tip of the shoot. The bags must be
firmly fitted and fixed to make them more secure.
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