The hidden helpers for plant and soil health.
Microbes, or microorganisms, are crops' hidden helpers. These tiny bacteria and fungi work behind the scenes to assist plants as they grow. In addition, they are vital to the overall health of the soil. Good soil health is paramount to providing enough food, fuel, and fiber for the world’s growing population. Farmers actively work to protect the soil in and around their farm and harnessing the power of microbes can be an important part of their soil management practices, as they protect the environment by using natural resources efficiently.
Microbes improve soil health in a variety of ways:
Microbes as Maximizers
Microbes act as maximizers, helping crops use the natural elements available in soil more efficiently.
Nitrogen is critical to plant growth; it is used to produce chlorophyll which is essential for photosynthesis. Generally, crops pull nitrogen from the soil around them. However, some agricultural processes as well as extreme weather allow for nitrogen to escape from the ground. Microbes can help.
When microbes are present where organic matter is decomposing, for example following the clearing of cover crops or after harvest, they can capture the nitrogen released during the process. The microbes then transfer that saved nitrogen to growing plants through their roots.
Phosphorous is another element essential to plant growth. It is not only a key component in photosynthesis, but it also stimulates root development, increases stalk and stem strength, and improves plants’ resistance to disease.
While there is plenty of phosphorus in soil, it cannot be dissolved by the plant directly for its benefit. Microbes help to break down the phosphorous present in soil, freeing it from the organic bonds keeping it there, so that plants can use it to grow.
Nitrogen and phosphorous are two of the most important nutrients a plant needs to grow to its full potential, but they are not the only components crops need. Microbes help by shepherding important elements like water, and nutrients like potassium to the plant’s roots.
Microbes as Protectors
Microbes also protect growing plants from insects and disease.
Some microbes work with plants to stop harmful fungi from crippling their growth. By creating a barrier around the crops’ roots, these microbes protect them from soil-bound, harmful fungi. Other microbes work their way up the plant to coat their leaves in a protective barrier against airborne pathogens.
There are some microbes that work as natural pesticides1, destroying unwanted insects before they can even reach the plant. For example, Bacillus thuringiensis (Bt), a commonly used, naturally occurring pesticide, produces crystal proteins that are completely safe for humans but disruptive to the digestive system of certain insects. These microbes are not harmful to humans but can be deadly to pests.
Microbe Partners in Soil Health
Nematodes are microscopic worms that eat other microorganisms within soil. While many microbes are beneficial to crops, many nematode species also have a beneficial and important role. When they eat other microbes, ammonium (NH4+) is released back into the soil. Plants can then break the ammonium down and use the beneficial nitrogen contained within. In addition, nematodes act as buses (or transportation vehicles) as they travel through the soil, picking up and dropping off microbes that attach to their exterior along the way.
Harnessing Microbial Powers for Good
Several factors—including erosion and temporary ponding or flooding—can lead to the depletion of microbes in a field’s soil. In addition to using modern agriculture practices like cover crops and reduced tillage, farmers can now also improve their crops’ chances for healthy growth by adding a microbial coating directly to seeds prior to planting. The coating ensures the right microbes are as close as possible to the plant as it grows, helping to maximize natural elements already present in the soil like water, nitrogen, and phosphorus and protecting against insects and disease. Farmers are constantly learning from the soil, improving their ability to sustainably harvest enough food, fuel, and fiber to satisfy the world’s growing demands.