Do all cloned plants have the same genetic material? why or why not?

A new study of plants that are reproduced by 'cloning' has shown why cloned plants are not identical. Scientists have known for some time that 'clonal' (regenerant) organisms are not always identical. Now researchers believe they have found out why this is the case in plants: the genomes of regenerant plants carry relatively high frequencies of new DNA sequence mutations that were not present in the genome of the donor plant.