of Molecular Genetics
Raupp et al.,
for Genetic Stocks
of Chromosome Variations
- Additive gene
One of a group of non-allelic genes affecting the same phenotypic
characteristics and each enhancing the effect of the other.
Alien addition A genome that contains one or more chromosomes
from another species in addition to the normal complement of
Anastomosis The joining of two or more cell processes
to form a branching system.
Basic population A population established through multiple-parent
crossing, which has wide genetic diversity and genetic variation.
It is the base of recurrent selection to improve the population.
Booting stage The wheat growth stage at which the head
has formed but has not emerged from the leaf sheath.
Bridge parent A parent that is sexually compatible with
two reproductively isolated species and can be used to transfer
genes between them.
Callus The cluster of cells that results from tissue culturing
a single plant cell.
Carbendazim 2-(methoxycarbonylamino)-benzimidazole, a
C-banding A method for producing stained regions around
Chlorogenic acid 1,3,4,5-tetrahydroxycyclohexanecarboxylic
acid 3-(3,4-dihydroxycinnamte), a plant metabolite.
Combining ability Average performance of a strain in a
series of crosses.
one of a large family of sesquiterpene epoxide toxins known as
a systemic fungicide.
Disomic Having one or more chromosomes duplicated but
not an entire genome duplicated.
Dominance Referring to alleles that fully manifest their
phenotype when present in the heterozygous state.
Epidermis An outer layer of primary plant tissue that
is usually one cell thick and provides protection to underlying
Gametocidal gene A gene encoding a product that destroys
cells that divide to produce the gametes.
Glume One of the two empty bracts at the base of the spikelet
Hypha A filament of a fungal thallus.
Jointing stage Wheat growth stage at which the first stem
node is visible above ground.
Land race A locally developed line of wheat.
Long-term Gene Pool A population established for long-term
breeding goals, with wide genetic variability. Lower selection
pressure is applied when it is improved through recurrent selection.
It can provide genetic variability to other gene pools.
Monosomic The condition in which one chromosome of one
pair is missing.
Necrosis Localized death of plant tissue often characterized
Ovary The ovule-containing region of the pistil of a flower.
Ph gene A chromosome pairing controlling gene. When dominant,
it inhibits pairing of homoeologous chromosomes; when recessive,
the control of homoeologous chromosome pairing is relaxed.
Polymorphism The existence of two or more genetically
different classes in the same interbreeding population.
Rachis The elongated axis of an inflorescence.
Random amplified polymorphic DNA Randomly generated oligodeoxyribonucleotides
that serve as primers in reactions involving reverse transcriptase
and annealing to complementary sequences in the template nucleic
Recurrent selection Crossing an offspring and one of its
parents or an individual genetically identical to one of its
Resistance Resource Gene Pool A population rich in genetic
variability of head scab resistance. The pool is kept to improve
the resistance with a stronger selection and accumulate the resistance
genes through recurrent selection.
Sclerenchyma A supporting tissue in higher plants composed
of cells with walls that are thickened, lignified, or mineralized.
Sector A part of a fungal culture with a visibly changed form
Short-Term Gene Pool A population established for short-term
breeding goals, with better agronomic performance and lower genetic
variability. Stronger selection is adopted, simultaneously, for
head scab resistance and agronomic traits, such as yield potential
characters, plant height, maturity and so on.
Somaclonal variation The appearance of new traits in plants
that regenerate from a callus in tissue culture.
Spikelet One of the small bracteate spikes that make up
the compound inflorescence of grasses.
Substitution line A line in which one or more chromosomes
have been replaced by chromosomes from a different species.
Thiophanate methyl Dimethyl4,4-O-phenylenebis (30thioallophanate),
a systemic fungicide.
Thiram Tetramethylthiuram disulfide, a protective foliar
Transgressive segregation Progeny phenotypes outside the range
that occurs in the parents, usually attributed to polygene segregation.
a systemic fungicide.
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