Answer:
Parent with big yellow apple= AArr
Parent with small red apple= aaRr
Explanation:
According to the given information, all the progeny has big apples and the trait "small size" is not expressed in any of them. This means that the parent plant with "big" apples was homozygous dominant and had an "AA" genotype. This is why there was no segregation of alleles and all the progeny had "big" apples.
On the other hand, both "red" and "yellow" colored apples were obtained in the progeny. This means that the parent plant with "red" apples was heterozygous for the trait "Rr". Segregation of "R" and "r" alleles during gamete formation led to the production of two types of gametes. Half of the gametes from this parent plant have an "R" allele while the rest half have an "r" allele.
Therefore, the genotype of parent plants are as follows"
Parent with big yellow apple= AArr
Parent with small red apple= aaRr