In a study from the University of Washington, scientists have successfully introduced microbes into soil to make phosphorus more available to the roots of agricultural crops. The researchers collected the microbes from wild trees growing along the Snoqualmie River.
When phosphorus is applied in a fertilizer, chemical reactions with other minerals cause it to get locked up in the soil as phosphate, which makes it inaccessible to plants. To overcome this issue, farmers often use excessive fertilizer applications, leading to a buildup of chemicals that can pollute nearby waterways in agricultural runoff.
Phosphorus is one of the primary nutrients that is essential for plant growth, and it is needed for plants to complete their normal production cycle.
“Crop productivity is constrained by the bioavailability of water-soluble nutrients, especially phosphorus in the form of phosphate,” wrote the study authors. “The efficiency of phosphorus acquisition, in which fine roots play a critical role, is important in addressing global food and bioenergy security issues that arise from increasing world population and climate change. In nutrient-limiting environments, plants are known to form associations with microorganisms capable of increasing the bioavailability of nutrients.”
Endophytes, which are bacteria or fungi that live inside a plant for at least some of their lifecycle, can be thought of as “probiotics” for plants, explained study senior author Professor Sharon Doty. Previously, her team demonstrated that microbes can help plants survive and even thrive in nutrient-poor environments.
In the current study, the researchers found that endophytic microbes collected from wild trees can unlock valuable phosphorus from the environment. The microbes simply break apart the chemical complexes that form phosphate.