|Fertilizer pollution is a major problem due to its adverse effects on waterways like rivers and lakes / Photo by: ninamalyna via 123RF|
Fertilizer pollution is a major problem due to its adverse effects on waterways like rivers and lakes. So, researchers conducted studies on plants and found genes that could reduce excess phosphorus from fertilizer products.
The investigation was conducted by a research group at Boyce Thompson Institute. Their findings revealed a pair of plant genes that could control phosphate levels, which would decrease contamination to bodies of water. They published the results in the journal Nature Plants.
New Plant Genes to Fight Fertilizer Pollution
Farmers normally use fertilizers to boost the growth of their crops and meet the demands of the ever-growing population. However, the use of fertilizers can cause environmental problems like soil and water pollution. This is because fertilizer products typically contain high levels of nitrogen, phosphorus, and potassium compounds that can be flushed into waterways, such as ponds, reservoirs, rivers, and lakes, polluting them and rendering them unsafe for animal and human consumption.
At Boyce Thompson Institute, researchers discovered a potential key in reducing the levels of phosphate, a derivative of phosphoric acid, in fertilizers. A pair of plant genes exhibited a capability of regulating the chemical. Thus, application of the genes in biotechnology could mitigate the adverse effects of fertilizer use in farming.
|Farmers normally use fertilizers to boost the growth of their crops and meet the demands of the ever-growing population / Photo by: A. Singkham via 123RF|
The discovery of the plant genes was inspired by Maria Harrison, an adjunct professor at Cornell University. Harrison focused on the symbiotic relationship between plants and a type of fungus called arbuscular mycorrhiza or AM. AM fungi could colonize plant roots and create an interface where the plant trades its fatty acids for nitrogen and phosphate. As such, the two organisms could supply each other with essential nutrients, especially useful during dry spells and droughts. While the symbiotic relationship works for both sides, plants never let the fungi to go out of hand. Plants with AM use natural mechanisms to prevent excessive fungi colonization.
Researchers dug deeper on the biological processes that allowed plants to monitor the colonization of AM. In the lab, the team conducted gene testing and detected the short proteins called CLE peptides encoded within. The peptides were found in Medicago truncatula and Brachypodium distachyon plants.
|The discovery of the plant genes was inspired by Maria Harrison, an adjunct professor at Cornell University / Photo by: lightwise via 123RF|
Furthermore, the peptides were identified to be involved in cellular development and stress response. The team looked for these peptides in other plants and confirmed its presence throughout the plant kingdom, including green algae and flowering plants.
Additional tests were performed to learn more about the CLE genes. Results revealed that two of the genes acted as modulators of the AM fungi colonization in symbiosis. One of the genes called CLE53 could reduce the colonization rates to prevent the fungi from occupying beyond the roots. The other gene called CLE33 could decrease the colonization rates once the plant received enough supply of phosphate.
How the Plant Genes Can Fight Fertilizer Pollution
"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," explained Harrison, as quoted by Science Daily, an American website that distributes press releases about science.
Since AM trades its phosphate with plants to get fatty acids, modifications in the CLE peptides in plants could help lessen the phosphate levels in farmlands. Researchers pointed out that the peptides function through the SUNN receptor protein and modulate a compound called strigolactone used by plants in synthesis.
If modified, the peptides could stop additional phosphate production from AM once the roots are colonized or if the supply is adequate. As a result, the plant would immediately halt the strigolactone synthesis, which pauses the activity of the fungi until the phosphate has been consumed.
The research team is now looking into the molecules responsible for the CLE genes. They are also investigating how the genes will react to high levels of phosphate.
Data from the Environmental Protection Agency, a US organization for environmental protection, showed that fertilizer pollution is one of the major contributors of nutrient pollution in the world. Nitrogen and phosphorus have been known as substances that can pollute both air and water, destroy ecosystems, and kill aquatic life.
As of March 2012, an estimated 15,000 water bodies in the US have been impaired by the excessive amount of nutrients. That represented about 101,000 miles of rivers and streams in the country containing imbalanced levels of nutrients. Moreover, 3.5 million acres of lakes and water reservoirs were detected with nutrient imbalance due to nitrogen and phosphorus levels from different sources.
Waterways with nutrient pollution are prone to algal blooms, wherein harmful algae grow at an uncontrolled rate. Algal blooms block sunlight and consume resources that plants and marine life use. Thus, most areas with algal blooms are found with dead fishes and other aquatic animals. Nutrient pollution and algal blooms are detrimental to industries, commercial establishments, and even residential areas.