Glossary Plant Breeding

Intervening Sequence. An Intron; a segment (comprising several nucleotide pairs) of
largely unknown function within a gene. The segment is initially transcribed, but it
gets eliminated from the functional mRNA transcript.
Intrachromosomal Recombination. Recombination resulting from crossing-over
between two gene pairs.
Introgression. The transfer of desirable genes from the wild species into the cultivated
ones.
Introgressive Hybridisation (Anderson 1949). A kind of interspecific hybridisation. It
consists of recrossing of interspecific hybrids with the parental species in such a way
that both the species are enriched with desired features of each other without loosing
their taxonomic identity. It aims at broadening the genetic base of different species.
Sometimes, introgression is difficult to detect because genetic contamination is very
slight.
Intron. A sequence of a gene that is transcribed into nuclear RNA but is removed from
functional transcript before translation of the message. After removal from mRNA, it
is rapidly degraded.
Intuitive Approach. An approach of choosing parents for crossing programme on the
basis of phenotypic assessment of agronomic, pathological and quality traits in
contrast to predictive approach that is based on genetic analysis. Breeders most
frequently use it.
Inversion. A rearrangement of a chromosome segment so that its genes are in reversed
linear order. It is a kind of chromosome mutation consisting of the removal of a
segment, its rotation through 180° and its reinsertion in the same location.
Inverted Repeat Sequence. A sequence found in identical but inverted form (for
example, at the opposite ends of a transposon).
Ionizing Radiations. Very high-energy radiations that can remove electrons from atoms
and attach them to other atoms, thereby producing positive and negative ion pairs (α,
β, γ, χ-rays, for example).
IPRs. Intellectual Property Rights. It is a monopolistic right, granted under law to
inventions for a fixed period to exclude others from imitating, manufacturing, using
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