I expect that by the time you finish the best specialization will still be genetics. Texas, did you mean A&M should be as good as anything you will find east of Davis.

Some blogger reports - I've made no attempt to check this - Humboldt State University, home to the largest undergraduate botany program in the country.

Hello Beroan,
Just what really interests you at the moment? List everything that you enjoy. And why are you interested in botany?
What kind of lifestyle choices are you used to living under?
Before deciding upon a major of Botany you need to ascertain if there is a particular field that might be of interest to you. Are you into chemistry or geology?
Texas A & M is an excellent school but you need to look closely at what in their majors listing is in the general area of interest to you. Check the link below.

Here is a link that might be useful: College of Ag & Life Science Texas A & M

With population growth and a continuing decrease in arable acreage, there is an urgency to increase the yield per acre. The most efficient way to do this is by improved varieties. Plant geneticists will be in demand and Brazil seems to have set up an infrastructure to attract them.
Now if only I were 30 years younger, I would learn to speak Portuguese.

Portuguese? Really?
Isn't this about a young person making up their own mind
based upon their own interests and lifestyle needs.
There are many ways to increase productivity besides
introducing engineered plants that can be easily exploited
by the few to rip off farmers and vis a vis consumers.

Here is a link that might be useful: The controversy

Very much has been said and very little has been gained to assuage the hunger pangs of a large section of the world's population. It seems to me that every bit of scientific, progress has been countered by emotional roadblocks. The intersection of population growth and diminishing arable land needs to be converted to something more like a "roundabout".
This can be the challenge to "a young person making up their own mind" about how their own interest(s) can be channeled to provide an income to themselves and a benefit to others in need.
In an era of "outsourcing" the answer might well be "Outsource yourself".

As a current graduate student, I would recommend the following fields pertaining to Botany (dont rule out Horticulture...)
-Molecular Ecology
-Conservation Biology
-Plant Breeding, does not need to be transgenic
-And yes, genetics. This last field might not satisfy you if you prefer working in the soil or checking out wild flowers, but you will get a job upon graduation (as you should with the other concentrations)

As for hunger pangs. How about steadily decreasing population to attain a sustainable level. How about reducing poverty so that people can farm food rather than cash crops for export? This is not emotion. This is logic.