Also found in: Thesaurus, Medical, Wikipedia.
Related to testcross: incomplete dominance


 (tĕst′krôs′, -krŏs′)
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·cross·ing, test·cross·es
To subject to a testcross.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(ˈtɛstˌkrɒs) genetics
(Genetics) a genetic test for ascertaining whether an individual is homozygous or heterozygous
vb (tr)
(Genetics) to subject to a testcross
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈtɛstˌkrɔs, -ˌkrɒs)

a genetic test for heterozygosity in which an organism of dominant phenotype, but unknown genotype, is crossed with an organism recessive for all markers in question.
test′-cross`, v.t.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.testcross - a cross between an organism whose genotype for a certain trait is unknown and an organism that is homozygous recessive for that trait so the unknown genotype can be determined from that of the offspring
hybridisation, hybridization, hybridizing, interbreeding, crossbreeding, crossing, cross - (genetics) the act of mixing different species or varieties of animals or plants and thus to produce hybrids
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
Number of families in maize testcross populations with different numbers of parents.
Each of the 12 accessions was hybridized with NC1125-2 and [F.sub.1] individuals were subsequently crossed as females to TMV-susceptible (TM[V.sup.S]) cultivar 'K326' to produce 12 testcross families.
To overcome this problem, Melchinger (1987) proposed the testcross generation means analysis.
Genotype by environment interactions and agronomic performance of doubled haploids testcross maize (Zea mays L.) hybrids.
In the pseudo-testcross configuration, Mendelian segregation was tested for all markers at a 5% signification level by performing a chi square (X2) goodness-of-fit test to testcross (1:1) and intercross (3:1) marker ratios.
In addition, different types of segregating populations derived from the same cross have been applied, for example, the F2:3 families [2] and immortalized F2 populations [8] derived from Zhenshan 97/Minghui 63 and recombinant inbred lines (RILs) derived from Lemont/Teqing and its backcross and testcross populations [11].
Bernardo, "Correlation between testcross performance of lines at early and late selfing generations," Theoretical and Applied Genetics, vol.
The objective of this study was to evaluate four testers with different genetic structures (single cross hybrids, with narrow genetic basis, and open pollinated varieties, with broad genetic basis) and different types of grains (flint and dent) for identification of superior inbreed lines in testcross.
Four possible exercises are presented: two versions of a dihybrid testcross and two versions of a three-point testcross.
In this situation, there is a way to determine the genotype for a plant with a dominant phenotype (in this case yellow seed)--a testcross is performed.
Sprague and Eberhart (1977) reviewed results from 50 yr of published studies and concluded that "selection practiced during inbreeding has less effect on combining ability for yield than was once thought;" however, selection "is highly effective in modifying lines with respect to general vigor, maturity, and insect or disease resistance." This conclusion is at the heart of common maize breeding practices (Bauman, 1981, as cited by Hallauer, 1990): Most breeders rely on visual selection (including for disease resistance, inbred vigor, and producibility), followed by testing combining ability for grain yield; 60% of breeders in USA delay first testcross evaluation of grain yield to [S.sub.3] (33%) or [S.sub.4] (27%) generations.