Nematodes and Their Impact on Soil Health | Crop Protection | Corteva Agriscience
 7/16/2021

Nematodes and Their Impact on Soil Health

Good and Bad Nematode graphic

Maintaining healthy soil is key to the success of your farm, as it helps sustain a productive environment for your crops, both today and in the future. Understanding and managing soil health is vital for successful growers.

Doran describes soil health as “The capacity of soil to function as a vital living system, within ecosystem and land-use boundaries, to sustain plant and animal productivity, maintain or enhance water and air quality, and promote plant and animal health” (Doran et al. 1996).

No matter the soil type, sound agricultural practices can help improve soil health. Some important farming fundamentals include conservation tillage, crop rotation, nutrient management and the use of cover crops.

It is important to understand that soil is a living and active part of the farm which lies beneath your feet. It contains a variety of beneficial organisms including bacteria, fungi, protozoa, macro- and micro-arthropods and nematodes, which contribute to nutrient cycling, natural disease and pest suppression, and improvement of your soils structure.

What Are Good Nematodes?

Nematodes are one of the most diverse and abundant groups of animals in the soil, and plants almost always interact with nematodes during their lifecycles.

Good nematodes, also known as beneficial nematodes, contribute to the soil in various ways and are involved in nutrient cycles that boost plant growth. Different types of nematodes feed on bacteria, fungi, insects, and even bad nematodes. These helpful organisms play an important role in keeping destructive plant pests and diseases at bay, thus promoting both soil biodiversity and health.

Nematodes are one of the most diverse and abundant groups of animals in the soil, and plants almost always interact with nematodes during their lifecycles.

Healthy soils are rich in beneficial soil organisms that help plants improve water and nutrient usage and suppress pests and diseases, which in turn enhances the tolerance of crops to other environmental stresses such as weather events. This ultimately results in better long-term productivity of your land and the profitability of your farm.

What Are Bad Nematodes?

Bad nematodes, also known as plant-parasitic nematodes, are microscopic and invisible to the naked eye, but may exist in extremely large numbers and have the power to ravage a crop and cause significant yield loss. While preserving good nematodes promotes soil biodiversity and health, controlling bad nematodes is essential to keeping your crops healthy and productive. 

There are many types of plant-parasitic nematodes, and they are identified based on morphology under a microscope, typically by a specialist. Often, they are called the “invisible enemy.”

Root-knot nematodes are one of the most important types of plant-parasitic nematodes. Once they enter the crop roots they cause knots, also known as galls. When these knots become visible on the roots this is the first sign of crop destruction.

 

 

The galls are feeding sites of the bad nematodes and significantly impair the ability of the plant to take up water and nutrients. Hundreds of nematode eggs come out of the galls and hatch in soil to reinfect the plant roots about every 30 days.

Root-knot nematodes occur widely around the world in numerous crops and cause estimated annual crop losses of more than $100 billion. Once in a field they will be there year after year.

Protecting the Good Nematodes and Reducing the Bad Nematodes

Understanding the role of beneficial nematodes in soil health is a key step toward optimizing crop production and sustaining your farm’s future. Conserving the good nematodes and controlling the bad ones can make a significant impact on your crops.

Root-knot nematodes occur widely around the world in numerous crops and cause estimated annual crop losses of more than $100 billion.

“You could spend a lot of money putting nutrients back into the soil with blended fertilizers, but it could be for nothing if nematode feeding has damaged those roots and the plant can’t access the nutrients,” independent crop consultant Joel Moor of Greenwood, Mississippi, says. “If that happens, you're more than likely not going to have a good yield.”

Using a nematicide that is gentle on the good nematodes while stopping the bad ones before they can find and infect the plant roots helps sustain the natural productivity of soil every agricultural cycle year after year.

Doing all you can to maintain the health of your soil supports your profitability today and the legacy of your farm for future generations.

Doran, John W. and Zeiss, Michael R. (2000). Soil health and sustainability: managing the biotic component of soil quality. Applied Soil Ecology 15, 3-11. https://digitalcommons.unl.edu/agronomyfacpub/15/