If an economically important crop such as the potato as highlighted in the illustration can only be produced by cloning, it is normal for scientists to be concerned because a single even of disease attack might end up wiping the entire crop away.
Cloning is more or less mitosis - a division of vegetative cells. In other words, there is no form of genetic recombination in clones. All clones have exactly the same genes as themselves and their parents.
The implication of an entire population of an organism having the same genetic composition is that they will be resistant and susceptible to the same limiting factors - be it biotic or abiotic. Just an event of a disease outbreak might end up wiping all the population away because there will not be any resilience.
More on the demerits of cloning can be found here: https://brainly.com/question/15364184