Good soils, soil health, proper drainage, climate, etc. would be contributing factors to high value land for agricultural use. Some of these factors are easier to change than others!
I would not consider the choice of seed type to be a significant factor in determining land value, although a history of high yields could certainly help, and there are better/worse choices when it comes to pairing a piece of land with a seed variety if your goal is high yield. A good steward of the land knows how to profit from it sustainably by maintaining soil health and nutrient balance, and healthy and productive land is valuable.
Monsanto is one example of a handful of modern seed suppliers using the latest seed/trait technologies towards higher yielding crops. Aside from the buzz and controversy, farmers generally find their products to be favorable and profitable in modern agricultural systems.
Corn and soybeans (the two major cash-crops, at least in my area) have to be replanted every year, regardless of seed supplier.
