Sugarcane is the world's most harvested crop by tonnage and has shaped world history, trade, and geopolitics, now responsible for 80% of the world's sugar production. Traditional sugarcane breeding methods have been effective in producing varieties adapted to new environments and pathogens, but sugar yield improvements have recently plateaued. The cessation of yield increase may be due to limited genetic diversity within the breeding population, long breeding cycles, and the complexity of its genome. Now, an international research team has created a polyploid reference genome for R570, a typical modern sugarcane variety.
Domestication of sugarcane began about 10,000 years ago. The first “sweet” varieties (Saccharum officinarum) derived from robustum sugar.
However, all modern varieties are derived from several interspecific crosses made by breeders a century ago between “sweet varieties” and “sweet varieties.” Saccharum officinarum And that 'wild' natural sugar.
Sugarcane hybridization has led to major advances in disease resistance and adaptation to stressful environmental conditions. However, early generation hybrids also had much lower sugar yields due to the greater contribution of the wild genome.
The complexity of the hybrid sugarcane genome and phylogeny is R570 varietyproduced by a breeder on Reunion Island in 1980.
“The sugarcane genome is very complex because it is large and contains more copies of chromosomes than a typical plant, a feature called polyploidy,” said researchers at the Hudson Alpha Institute for Bioengineering. said Dr. Jeremy Schmutz and colleagues.
“Sugar cane has about 10 billion base pairs, the building blocks of DNA. By comparison, the human genome has about 3 billion genes.”
“Many parts of sugarcane DNA are identical within and between different chromosomes, which makes it difficult to correctly reconstruct all the small segments of DNA while reconstructing the complete genetic blueprint. Masu.”
“We solved the puzzle by combining multiple gene sequencing technologies, including a newly developed method known as PacBio HiFi sequencing that can precisely sequence longer sections of DNA.”
“This was the most complex genome sequence we have ever completed,” Dr. Schmutz added.
“It shows how far we have come. This is something that seemed impossible 10 years ago. We are now reaching goals that we thought were impossible with plant genomics. We have been able to achieve this.”
CSIRO researcher Dr Karen Aitken said: “This groundbreaking result addresses the critical challenge of stagnant sugar yields by harnessing previously inaccessible genetic information from the sugarcane genome. ” he said.
“This is a major step forward for sugarcane research and will improve our understanding of complex traits such as yield, adaptation to diverse environmental conditions, and disease resistance.”
“We are working to understand how specific genes in plants are related to the quality of the biomass obtained downstream, which can then be turned into biofuels and bioproducts.” said Dr. Blake Simmons, a researcher at the Joint BioEnergy Institute.
“A deeper understanding of sugarcane genetics will help us better understand the plant genotypes required for the production of sugar and bagasse-derived intermediates needed for sustainable sugarcane conversion technologies at scales relevant to the bioeconomy.” and be in control.”
of result appear in the diary Nature.
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Al Healy other. Complex polyploid genome structure of sugarcane. Nature, published online March 27, 2024. doi: 10.1038/s41586-024-07231-4
Source: www.sci.news
