China has completed the genome sequencing of three varieties of cassava, the roots of which are used to produce ethanol, scientists said Monday.

The genome sequencing can shed light on the cassava plant as a source of biomass energy. It also lays the foundation for enhancing cassava's ability to grow on barren soil and resistance against drought, said Peng Ming, head of the Biology Institute of the Chinese Academy of Tropical Agricultural Sciences.

China is taking the lead in genetic research into the cassava. The sequencing has covered more than 95 percent of the three cassava varieties' genes. The United States has only covered 65 percent of one variety, Peng said.

No other country has published research of the cassava genome sequencing so far, Peng said.

The sequenced varieties are Ku50 (high starch content cassava), W14 (original cassava) and CAS36 (sweet cassava).

The three varieties' draft genome maps would be completed in March, Peng said.

Cassava is extensively grown in southern China for food and as a new source of biomass energy. "Genetic researches will enable cassava to grow in the colder and drier northern China," Peng said.

(Xinhua News Agency January 18, 2010)