by Sarah Miller, Sustainable Plant Systems major
Soybean Cyst Nematode disease is a large issue in agriculture today. It is a large unforeseen problem because only the soybean nematode cyst can be seen with the naked eye. Soybean cyst nematode damage is also costing American farmers over one billion dollars a year in crop losses. Many times the soybean cyst nematode can be blamed for other diagnostic problems such as a nutrient deficiency or it could be missed if another pathogen is present.
The soybean cyst nematode is also known by its pathogen name Heterodera glycines. It can infect soybeans and other plants in the legume family. It is found in soil and plants, and has a sedentary endoparasite lifestyle. The sedentary endoparasite lifestyle means that once it is inside the plant root it stays inside the root for the rest of its life cycle.
To know if you have the soybean cyst nematode you should be able to recognize the signs and symptoms. The signs of soybean cyst nematode are the female egg cyst that a very small but can be seen in the soil often by plant roots. The symptoms of soybean cyst nematode disease are stunting, yellowing and overall reduced yields in plants. Note that this is often similar to other problems.
Another great diagnostic tool to help you see if you have the pathogen in your soils is knowing the lifecycle of the soybean cyst nematode. The soybean cyst nematode overwinters in the soil and begins its life in a cyst, which is a remnant of the female’s body with unhatched eggs inside of it. After the eggs hatch from the cyst and the individual egg itself; it has the normal shape of the nematode and begins to infect a plant around it in the soil. After infecting the plant the soybean cyst nematode continues its lifecycle until till it reaches adulthood, then the males and females will exit the root to mate; the females with become a cyst after their lifecycle is complete.
To help the control the soybean cyst nematode there are a few useful management practices that can be used. Crop rotation can be used to disrupt lifecycles during different growing seasons. Planting resistant crop varieties and applying nematicides can also be helping in fighting the soybean cyst nematode.
This blog post was an assignment for Societal Issues: Pesticides, Alternatives and the Environment (PLNTPTH 4597). The views expressed are those of the author and do not necessarily reflect the views of the class, Department of Plant Pathology or the instructor.