The word "Burbank" can refer to a few different things, but in the context you're asking about, it primarily refers to an important person in agriculture: Luther Burbank. Here's a simple explanation:
Burbank (noun) refers to Luther Burbank, an American horticulturist who lived from 1849 to 1926. He is famous for developing many new types of fruits, vegetables, and flowers. His work helped improve agriculture and made it possible to grow better plants.
In summary, "Burbank" refers to the famous horticulturist Luther Burbank, whose work greatly influenced the development of new plant varieties.