testcross


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Related to testcross: incomplete dominance

test·cross

(test'kros),
Crossing of an unknown genotype to a recessive homozygote so that the phenotype of the progeny corresponds directly to the chromosomes carried by the parents of unknown genotype.
Synonym(s): backcross (2)

testcross

(tĕst′krôs′, -krŏs′)
n.
A cross between an individual exhibiting the dominant phenotype of a trait and an individual that is homozygous recessive for that trait in order to determine the genotype of the dominant individual.
tr.v. test·crossed, test·crossing, test·crosses
To subject to a testcross.

testcross

Etymology: L, testum + crux, cross
1 a cross between a dominant and a recessive phenotype to determine either the degree of genetic linkage or whether the dominant phenotype is a result of a homozygous or a heterozygous genotype.
2 a subject undergoing such a test. See also backcross.
Testcrossclick for a larger image
Fig. 295 Testcross. A testcross to find the genotype of the unknown parent.

testcross

a cross in which one partner is homozygous (see HOMOZYGOTE for the recessive alleles of the genes being investigated. The testcross progeny will indicate the GENOTYPE of the unknown parent. See Fig. 295 . Test crosses are used extensively in experiments to establish GENETIC LINKAGE. See also BACKCROSS.
References in periodicals archive ?
A total of 441 treatments, comprising the 426 testcross hybrids and 15 checks, were evaluated in nine trials in 7x7 lattices with two replications.
A mating scheme for the in cis dihybrid testcross is shown in Figure 3; the equivalent scheme for the in trans dihybrid testcross is shown in Figure 4.
Thus, a testcross would be a green-seeded plant (yy) x a yellow-seeded plant (either YY or Yy).
We have no explanation why the testcross of Pamela Marshall's Fls gave such a low recombination frequency.
I have used this calculation method successfully in a sophomore-level Fundamentals of Genetics Lab when the students were not able to generate testcross data.
Random nongenetic effects were added to the genotypic values to obtain testcross phenotypic values.
If this was correct, then some of the testcross progeny with 7DL should have acquired Dn5 through crossover and would have segregated for resistance.
Per se and testcross BLUP estimates were used to calculate phenotypic correlations and their standard errors (Lynch and Walsh, 1998; Kendall and Stuart, 1977).
Testcross grain yields of the midaltitude inbred lines under Striga infestation (Table 3) varied from 2210.
Sclerotinia tolerance of this line was selected by evaluating testcross hybrids that were artificially inoculated under mist irrigation.
de Bary] of RHA 447 testcross hybrids was evaluated by artificial inoculation under mist irrigation at the North Dakota Agricultural Experiment Station, Carrington Research and Extension Center, Carrington, ND.
Ears were harvested separately for each So plant to form testcross families.