backcross


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backcross

 [bak´cros″]
in experimental genetics, union between a heterozygote of the first generation and one of its parents or an organism genetically identical to one of its parents.
double backcross the mating between a double heterozygote and a homozygote.

back·cross

(bak'kros),
1. The mating between an animal that is homozygous at a locus of interest and an animal that is heterozygous, commonly from the same ancestral stock.
2. Synonym(s): testcross

backcross

(băk′krôs′, -krŏs′)
tr.v. back·crossed, back·crossing, back·crosses
To cross (a hybrid) with one of its parents or with an individual genetically identical to one of its parents.
n.
1. The act of making such a cross.
2. An individual resulting from such a cross.

back·cross

(bak'kraws)
Mating of an individual heterozygous at one or more loci to an individual homozygous at the same loci.
Backcrossclick for a larger image
Fig. 59 Backcross . Results from different parental types.

backcross

a genetical term describing a mating between a HYBRID organism and one of the original parental types. The results of a backcross depend upon the parental type.

A backcross to the recessive parental is diagnostic (since it reveals the genotype of the hybrid) and is called a TESTCROSS.

References in periodicals archive ?
Both markers were utilized at each backcrossed generation to identify plants possessing heterozygous alleles for the target gene.
Frequency of favourable allele for background QTLs under different ratios of QTL variance:MBLUP was background selection method, the result show in figure 4: during backcross phase, frequency of favourable allele for two background QTLs differ greatly among different ratios of QTL variance, backcrossing two generations, frequency of favourable allele for two background QTLs were 0.88 and 0.92 with the ratios of QTL variance, being 10% and 30% respectively, backcrossing five generations, the frequency rise to 0.98 and 1.00 under the same corresponding ratios of QTL variance.
The hierarchical methodologies and graphic projections were efficient in clustering populations according to the expected clustering standard based on the genetic parents, hybrid generation and backcross derivatives from both parents.
There are currently 74 backcross orchards, two seed orchards, four Phytophthora resistance screening programs, three Phytophthora resistance breeding orchards, 13 progeny test orchards, six special research plantings, several Germplasm Conservation Orchards (GCOs), and hundreds of ceremonial and demo plantings.
Throughout the experiment, except day 1, the SLs recorded in the backcross hybrid groups (BCP2, BPC2) were significantly greater than those of the CC2 control groups (P < 0.05), and an average growth advantage of 18% was detected during the second cycle of backcrossing.
In fact, with the exception of two individuals, marker numbers were more consistent with pedigrees involving three to seven backcross generations rather than the two generations of backcrossing actually employed.
Top half of table reflects backcross analysis in which backcross females carry an X chromosome from LUG; bottom half of table reflects backcross analysis in which backcross females carry an X chromosome from the multiple marker stock.
Chi-Squared values and probabilities of goodness of fit of segregation ratios of F2 and backcross generations in a study of inheritance of leaf trichomes trait in three cross combinations are shown in Table 4.
Erkul and Unay (2009b), the backcross generation with Cumhuriyet 75 was identified to have higher mean values for plant height and peduncle length.
Idaho 587 was derived from the third backcross of Stephens (Kronstad et al., 1978) to the imidazolinone-resistant line 'FS4' (synonym cv.
TACF's backcrossing method used Chinese-American hybrids produced at its research farms and backcrossed those to an entirely American parent.