I think mitosis if I’m wrong correct me. But we also have other answers so idk.
Answer:
If there is low genetic diversity, she needs to introduce something into the system to increase the variation. I would suggest breeding the orange trees with other new orange trees to change the allele frequencies, which is called gene flow.
Likely the fungi are attacking them somewhere that they have decreased resistance, and if more alleles were introduced, there would probably be evolution towards a genotype that promotes defense against these fungi.
Answer:
Adaptive radiation
Explanation:
Adaptive radiation occurs when an ancestral species move to a new environment that has various resources that are necessary for survival and also has environmental conditions that would ensure its offspring adapt well over time. In this new environment, the ancestral species would produce offspring with different traits and behaviors that will allow them to survive in this new environment while occupying their various niches. Over a relatively short time, different species arising from the common ancestor would occupy the new environment.