In a particular plant species majority of the plants bear purple flowers. Very few plants bear white flowers. No intermediate colours are observed. If you are given a plant bearing purple flowers, how would you ascertain that it is a pure breed for that trait? Explain.

Explanation

Test cross,Cross purple flower plant with a (homozygous) recessive plant white flower,if all the flowers of the progeny of the above are purple,the plant is homozygous dominant