The process by which food substances are moved to different parts of the plant by the phloem tissues is known as
translocation
Translocation is the movement of materials from leaves to other tissues throughout the plant. Plants produce glucose (sugars) in their leaves by photosynthesis, and carries it to the other nonphotosynthetic parts that require carbohydrates and other organic and nonorganic materials for their survival and growth.
This generally happens through the phloem tissues.