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Back cross is a cross between F 1 hybrid and one of the two parents ( either homozygous dominant or homozygous recessive). It is done to increase the desired trait whereas Test cross is a cross between an individual of unknown genotype and its homozygous recessive parent. It is done to test whether the unknown genotype is homozygous or heterozygous. So, the main difference between test cross and the backcross is that test cross is used to discriminate the genotype of an individual which is phenotypically dominant whereas a backcross is used to recover an elite genotype from a parent which bears an elite genotype.
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