NANNING — A Chinese research team from Guangxi University has successfully decoded the genome of the modern cultivated sugarcane variety Xintaitang No 22 (XTT22), shedding light on the highly complex allopolyploid genome of sugarcane and its evolutionary mechanisms.

Sugarcane plays a vital role in the production of sugar, alcohol and bioenergy, offering substantial economic and agricultural value. XTT22 was once the leading sugarcane variety in terms of planting area in China for 15 years. More than 90 percent of the country's fourth and fifth-generation sugarcane varieties were developed using it as a parent.

According to Liu Yaoguang, an academician of the Chinese Academy of Sciences, the genome of XTT22 decoded in this study is the most complete and highest-quality genome assembly of modern cultivated sugarcane to date.

However, earlier genome drafts of sugarcane faced significant issues, including incomplete chromosomes and highly fragmented sequences. As a result, obtaining a complete and accurate genome of modern cultivated sugarcane has remained elusive.

"This study is like drawing a detailed map of the sugarcane genome. In the past, the map was so vague that we could only roughly navigate it," said Zhang Jisen, research team leader from Guangxi University.

"Now, however, every 'street' and even every 'room' on the map is clearly marked," Zhang added.

Previously, sugarcane breeding primarily relied on traditional hybridization methods, where parent plants were selected based on experience to observe the performance of their offspring. However, this approach proved to be both time-consuming and inefficient.

Leveraging advancements in genomics, scientists can now use the "genomic map" to precisely pinpoint genes closely associated with sugarcane yield and sugar content, enabling more targeted improvements and optimization.

"With the widespread application of genomics in sugarcane breeding, the yield, sugar content and disease resistance of sugarcane are expected to see further improvements," Zhang said.

The research was recently published in the journal Nature Genetics.

Xinhua