Genetic Mixing in Grass Still a Surprising Mystery in Plant Genetics

Grass is still grass, right? Well, for some scientists its widespread presence belies one of the biggest mysteries in plant genetics.

Because in order for it to spread, it needs to wildly adapt to all facets of an ecosystem. Now, how can a single species of plant accomplish this with every fiber of its own genetic makeup?

The answer: It doesn't. It takes genes from others.

To date, there are about 10,000 species of grass in the world (including bamboo, as well as grains like wheat and rice). And across that wide variety, scientists have found that some independent grass species have inherited as many as 59 genes from others (including some very distant relatives)!

This was made possible by something called lateral gene transfer, which is simply a scientific term for getting the same DNA sequence without necessarily being born from the same organism. This is also subtler than creating full-on hybrids because the transferred genes are still a minority compared to the rest of the genes making up a species' genomes. On the other hand, it actually takes just one gene to make a massive difference in any organism's survival.

For a long time, this type of genetic transfer was believed to only occur in microbes such as bacteria. However, studies into the genetic makeup of grasses have proven this is possible even in larger, more complex organisms.

Still, scientists have not reached a consensus on exactly how this happens. Some suspect that it could simply be from contact with fragments of outside genetic material. Others hypothesize that it is more a combination of that as well as deliberate adaptation to improve survival.

Implications for plant genetics and genetic modification

Another highlight of all this recent research is that it greatly demonstrates the flexibility of plants to rapidly integrate traits from other species (at least, this has been the case for grass). Likewise, it has even been shown occurring the other way around with reports of some insects who have integrated a plant gene in order to become more resistant to plant toxins.

This phenomenon is not merely the result of human intervention but also the product of pure, natural evolution. Because in the midst of a grass' wild proliferation, it is also weeding out what transferred genes are not necessary for thriving.

Therefore, it begs the question: Just how many of the currently existing grass species have actually been born as a result of this constant mixing?

Mixed-gene grass goes beyond modern agriculture

Contrary to popular belief, the genetically modified organisms (GMO) have been produced in agriculture long before the term itself was coined. And with these recent discoveries on grass genomes, it is clear that modification predates farming itself.

Regardless of how the genes are transferred, it shows that grasses are surprisingly resilient when it comes to incorporating any traits that will allow them to enhance their spread, deter consumption and survive in hostile environments.

This adaptability can really go a long way for more applications in sustainable farming and even undoing the damage of human activity on local ecosystems.