This isn’t the referent of “knowledge systems.” The knowledge systems refer to indigenous knowledge concerning heirloom crops. It doesn’t refer to techniques of researchers.

Although the author does mention that heirloom seeds have been passed through families, this is distinct from the “knowledge of the required development and cultivation methods” for heirloom crops. This is the knowledge that has been maintained through regional exchange networks, and this is the referent of “knowledge systems.”

Hybridization techniques brought from outside North America are not the indigenous knowledge that “knowledge systems” refers to.

The author describes “knowledge” of development and cultivation methods for heirloom crops and how this knowledge has been preserved through community and regional exchange networks. The “knowledge systems” that must be preserved are those systems that pass on knowledge of these development and cultivation methods.

We have no reason to think the “knowledge systems” refer to “fail-safe techniques” for farming operations. The phrase refers to indigenous knowledge of cultivating heirloom crops.