I really want to go to Cornell but I need to expand my search

Look at the course offerings and tracks within the closest majors, and also research you could potentially participate in as an undergrad while majoring in biology, ecology, botany, etc.

Also, I don’t know how far from home you want to go (sounds like you’re on the east coast) and/or how much $ you want to spend, but UC Davis is a tippy-top school in this field as well, and has a Plant Biology major with a Plant Breeding and Genetics option within the major. OOS tuition is pricey though.