The world would be in a much worse situation hadn’t been for fertilizer-powered agriculture that helped us face the growing need for food of an ever-increasing population.
Although fertilizers are mostly inorganic chemical concoctions, the nutrients they provide to plants are natural, like nitrogen, which is one of the most potent greenhouse gasses, and phosphorus.
But, excessive soil fertilization is causing problems in the environment. Phosphorus usually finds its way through waterways underneath the ground, polluting ecosystems like water and air.
Fertilizer pollution, or nutrient pollution, is an environmental headache that’s only getting more challenging as more fertilizers are applied to the soil. Even organic soil additives, like manure, have their fair share of nitrogen and phosphorus, and other contaminants.
How Two Plant Genes Could Help Curb Fertilizer Pollution?
The adverse impact of fertilizer pollution doesn’t stop at air and water quality; it also indirectly affects human health.
It was recently found that fertilizers help some strains of superbugs spread their antibiotic resistance to other bacteria present in the soil. Talk of community support and generosity!
Because there’s an urgent need for a novel effective approach to reducing fertilizer pollution, a team of researchers has gotten to the genetic bottom of the problem.
A new study from Boyce Thompson Institute (BTI) uncovers the function of a pair of plant genes that could help farmers improve phosphate capture, thus reducing fertilizer pollution.
In their new research, the BTI team built on previous work of BTI Professor Maria Harrison on plants’ symbiotic relationships with a type of fungi called arbuscular mycorrhizal (AM).
This fungus develops in the roots of most vascular flowering plants where it creates a platform to exchange fatty acids for mineral nutrients, particularly phosphate, with the plant. AM fungi also help their host plants recover from environmental stresses like drought periods.
Harrison and Lena Müller, a postdoctoral scientist in Harrison’s lab, wanted to investigate the mechanisms of plants and AM fungi symbiosis and how plants control the fungi colonization. Specifically, they looked at genes that encode CLE peptides, small proteins in plants involved in cellular development and stress responses.
The team found that two of CLE genes, called CLE53 and CLE33, that play a key role as modulators of AM fungal symbiosis. The first gene reduces the AM fungi colonization rates at the roots level, while the other lower colonization rates when the plant decides there’s enough phosphate.
Harrison said:
“Being able to control fungal colonization levels in plant roots and maintain the symbiosis even in higher phosphate conditions might be useful to a farmer. For example, you may want the other beneficial effects of AM fungi, like nitrogen uptake and recovery from drought, as well as further uptake of phosphate… You might be able to achieve these benefits by altering the levels of these CLE peptides in the plants.”
As the researchers point out, it’s been known since the early 2000’s that plants can measure and then reduce fungi colonization, but this study reveals for the first time the molecular mechanism of this symbionts dynamic.
Next, the team plans to investigate more CLE genes and their functions, as well as additional CLE peptides. The study was published in Nature Plants journal.
But then why plant decides it had enough phosphate?