Why in news?
A global team of researchers recently announced the sequencing of sugarcane genome.
Why is it so significant?
- Sugarcane produces 80% of the world’s sugar.
- It has also emerged as the primary crop for biofuel production.
- The sugarcane genome is nearly 20 times bigger than that of rice.
- Its complex genetic makeup has so far posed challenges to classical sequencing approaches.
- So significantly, sugarcane is one of the last crop plants to be genome-mapped.
- In comparison, the rice genome was cracked nearly 14 years ago.
How was it done?
- Each of the 10 basic sugarcane chromosomes is duplicated in 8-10 copies with a total of more than 100 chromosomes.
- In comparison, the human genome has just 23 pairs of chromosomes.
- An earlier discovery that the genomic structures of sugarcane and sorghum being very similar helped here.
- Sugarcane and sorghum share large fragments with numerous genes in the same order.
- So scientists used the sorghum genome (which was sequenced years ago) as a template.
- The template was used to assemble and select the sugarcane chromosome fragments to sequence.
What are the benefits?
- Until now, breeding programmes were restricted to hybridisation and was followed by cumbersome field assessments.
- With the recent finding, sugarcane breeding will be able to enter the age of molecular biology.
- The finding will help scientists create a reference genome of sugarcane.
- The reference sequence can help in effectively analysing and comparing variations between various sugarcane varieties.
- It can also help develop new molecular screening techniques to supplement conventional breeding methods.
- Characteristics that contribute to improving a variety rely on the combination of several genes inherited.
- The traits may include yield, drought resistance and ability to withstand pest attacks.
- So if scientists can identify genes associated with these agronomic traits, they can easily be transferred to commercial varieties.
- This in turn could shorten the time required for getting a new variety to the field.
- Varieties - Theoretically, the maximum sucrose content that sugarcane can have is around 25%.
- This could be breached with the knowledge of molecular mechanisms involved in sucrose storage in the plant.
- Very significantly, sugarcane is a known water-consuming crop.
- Genetic sequences linked to enduring water stress can help develop varieties that require lesser water.
What lies ahead for India?
- The cracking of the sugarcane genome can transform the sector.
- But India needs to clarify its stance on GM foods as India does not currently allow GM food crops.
- This is essential to reap the benefit of the advances in sugar genome sequencing.
- Notably, Brazil (with largest area in the world under sugarcane) recently allowed commercial cultivation of the world’s first GM sugarcane.
Source: BusinessLine
