麻豆淫院

Monash researchers have made a breakthrough discovery about the invasion success of plants, with the revelation that large-scale genetic changes are the common ragweed's secret to rapidly adapting to new environments.

The research discovered 37 large-scale genetic changes, including "supergenes," that have enabled the noxious weed to rapidly invade diverse environments worldwide. The paper is in the journal Molecular Biology and Evolution.

Supergenes are clusters of mutations that have a strong chance of being passed down through successive generations because they are inherited as a unit, as opposed to normal mutations which are inherited individually.

They can maintain favorable trait combinations, giving invasive species an evolutionary edge to survive and thrive in a wide range of environments.

Led by Monash School of Biological Sciences research fellow Paul Battlay and Associate Professor Kathryn Hodgins, the study analyzed more than 400 whole-genome sequences of ragweed from its native range in North America and its invasive populations in Europe and Australia.

Dr. Battlay said while ragweed populations in Europe and Australia originated from distinct North American sources, they underwent parallel adaptation to new climates.

"This repeatability in genetic changes highlights the predictability of evolution when facing similar environmental challenges," Dr. Battlay said.

"Ragweed's ability to adapt so quickly and effectively to new environments is truly remarkable.

"What's even more surprising is that, despite completely different invasion histories in Europe and Australia, we found strikingly similar genetic changes driving adaptation in both regions."

Ragweed has aggressively spread to Europe, Australia and other regions, thriving in environments disturbed by humans, like roadsides and agricultural areas.

Its airborne pollen is a primary trigger for seasonal allergies, affecting millions worldwide. It also has significant implications for biodiversity and agriculture.

Despite undergoing a severe population reduction, also referred to as a "population bottleneck," the Australian ragweed population displayed strong genomic signatures of adaptation.

Associate Professor Hodgins said this demonstrates that bottlenecks do not necessarily limit rapid evolution, adding to the understanding of how invasive species can overcome genetic challenges.

"Structural variants, particularly these supergenes, allow plants like ragweed to keep crucial genetic combinations intact as they spread to new regions," Associate Professor Hodgins said.

"This genetic toolkit helps them adapt rapidly and repeatedly鈥攁 phenomenon that is not only fascinating scientifically but also critical to understanding how to manage invasive species."

Ragweed's ability to rapidly adapt has significant implications for public health and agriculture. As a leading cause of hay fever and major agricultural weed, its spread presents challenges that demand innovative management strategies.

"Understanding the genetic mechanisms behind ragweed's rapid adaptation can inform efforts to control its spread," Dr. Battlay said.

"This is a vital step in mitigating its impact on agriculture and human health."