Agriculture Reference
In-Depth Information
DIAGRAM OF SELECTION OF MONOECIOUS HEMP
Recurrent Phenotypic Selection - Individual
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year 1
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year 2
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year
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Registration in the
official catalogue of varieties
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year
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year
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Fig. 4.13.
The selection model based on recurrent individual phenotypes.
•
The best lines are crossed in order to
Selection using molecular markers
arrive at a hybridized result. The choice of
the number of parents is influenced by
various factors, but generally lies between
4 and 10.
This technique (or techniques) relies on a molec-
ular study of the genome and seeks specifically
to identify particular genes within certain plant
varieties. The genome of the plant species must
therefore be known, together with the identity of
any desirable genes. This technique may there-
fore complement larger programmes working
on the polygenic factors that affect yield.
These techniques are now widely prac-
tised and have been used on almost all species,
including, of course, hemp.
Certain research projects of varying ambi-
tion have been undertaken on hemp:
Subsequently, the seed is increased to produce
the seed stock required for industrial production.
This technique is best suited to alloga-
mous species of little economic importance.
Such species are unlikely to be the subject of
programmes seeking to create controlled
hybrid varieties (in the case of hemp, true
hybrids pose technical and economic
difficulties).
The use of this technique to improve
both hurds and grain is a relatively recent
development in France.
•
Molecular markers for male plants have
been identified. They have been used in
the production of seed stock but have not
