**6. Breeding improved varieties**

The early introduction of cassava to Africa and Asia presented a limited gene choice that limits the diversity available to farmers to select new varieties. For instance, a single clone was cultivated by majority of the farmers in Thailand until the 1990s [5]. As researchers across different institutes and several domestic breeding programs take advantage of the vast national breeding programs, they have excellent combinations of many useful traits. The availability of varieties has improved significantly in recent decades the genetic diversity available in gene banks. Breeding of high-yielding varieties with resistance or tolerance to biological and non-biological stress contributes to a significant increase in cassava yield and overall production.
