Topic: Biology

Scientists have discovered a new way to understand how complex plant genomes form. They used this method to study strawberries and found that they evolved through multiple rounds of hybridization.

Many important crops, like strawberries, have very complex genomes. These genomes are made up of multiple sets of chromosomes inherited from different ancestral species. But figuring out exactly how these genomes were formed can be very difficult. A new study has introduced a method to untangle these complex genetic histories. This method looks at special DNA sequences called long terminal repeat retrotransposons. By comparing patterns of similarity among these elements across chromosomes, researchers can identify distinct subgenomes and estimate when major genome-merging events occurred. When applied to the cultivated octoploid strawberry, this technique revealed a step-by-step evolutionary history shaped by multiple rounds of allopolyploidization, providing new insight into how complex plant genomes form and diversify over millions of years.

The study also tested this method on well-studied allopolyploid crops like teff and cotton. In both cases, the method successfully distinguished known subgenomes and separated events that occurred before and after polyploidization.

This new approach can help scientists understand how complex plant genomes form and evolve without relying on known progenitor species.

Why It Matters

Understanding how strawberries evolved can help us improve crop breeding and develop more sustainable farming practices. This knowledge can also contribute to the development of new crops that can thrive in changing environmental conditions.

Key Facts

• The cultivated octoploid strawberry has a complex genome formed through multiple rounds of allopolyploidization.
• Long terminal repeat retrotransposons are special DNA sequences that accumulate in characteristic patterns within specific evolutionary lineages, preserving molecular evidence of past events.
• Scientists have developed a new method to reconstruct the evolutionary history of complex polyploid genomes without relying on known progenitor species.

Key Terms

Allopolyploidization

The process by which two different plant species combine their genetic material to form a new hybrid species.

Implications

Understanding how strawberries evolved can help us improve crop breeding and develop more sustainable farming practices. This knowledge can also contribute to the development of new crops that can thrive in changing environmental conditions.