Insect and Bug Guide: Beet Cyst Nematodes
- Old Oak Homestead
- Feb 2
- 5 min read
Updated: Mar 3
BEET CYST NEMATODE: attacks over 200 plants including beets (table and sugar), brassica plants, rhubarb, and spinach.
Beet cyst nematodes are microscopic parasitic worms that really threaten plant health and crop yields. They can infect plants of all ages at their roots. As many as five generations of beet cyst nematodes can occur especially when the weather is very warm. Management has traditionally been problematic as they can persist for years in soil without a host. Their remarkable persistence is due to their ability to produce a cyst, normally white-yellow in color, which is the hardened dead body of the female nematode that surrounds and protects the eggs from adverse environmental conditions. Each cyst contains several hundred dormant eggs which hatch slowly over years when stimulated by moisture and root exudates from growing host plants.
The beet cyst nematode can cause significant crop failure to the following plants
Spinach
Rhubarb
Beets (table and sugar)
Brussel Sprouts
Cabbages
Chinese cabbages
Cauliflowers
Broccoli
Turnip
Radish
Damaged Caused by Beet Cyst Nematodes
An entire crop can be affected and in young plants this can be devastating as it can result in severe stunting of growth and even death of the plant. Beet cyst nematodes feed on plant roots, reducing the plant’s ability to take up nutrients and water. Therefore above ground symptoms look like nutrient deficiency or drought — reduced stand, poor growth, stunting, yellowing and wilting.
Management of Beet Cyst Nematodes
There is probably not much that can be done for a crop that has been affected by the beet cyst nematode. The nematode invades the roots of the plant, leading to the formation of cysts that contain eggs, they can persist in the soil for many years without any host, making it a challenging pest to manage. Because of this resilience and the lasting impact of the beet cyst nematode on the soil ecosystem, it has been the traditional way of managing beet cyst nematodes to implement a strategic crop rotation. This involves alternating the types of crops grown in a specific field over a series of seasons. By not growing sugar beets or other susceptible crops for a couple of years other crops are planted that are non-hosts to the nematode, such as cereals or legumes, which do not provide a suitable environment for the nematodes to thrive. Chemicals have also been used to try and control beet cyst nematodes, but they become resilent to the chemical controls. All that ends up happening in the soil is that that good guys die and the bad guys live.
However, biological controls are another important way of control that are worthy of consideration.
Biological Controls
Research has shown that use of a soil fungus that is beneficial for stopping and preventing beet cyst nematodes from thriving in your garden. Microbes developed a wide array of strategies that help attack and kill cyst nematodes. Through specialized structures, such as constricting rings, three-dimensional hyphae networks, and adhesive spores, for example, predatory fungi can trap nematodes and prevent them from escaping. Opportunistic saprotrophic fungi attack nonmotile stages, like eggs, cysts, and Meloidogyne females. Endoparasitic fungi have specialized structures and strategies to feed on nematodes by luring them toward spores and forming a penetration peg upon contact, from which hyphae grow and colonize the pseudocoelom, resulting in the rupture of organs and tissues.
Many bacteria and fungi (some of which are endophytes), including arbuscular mycorrhizal fungi (AMF), have plant-promoting effects instead and can induce plant defense mechanisms.
It is for these reasons why maintaining a healthy soil food web is critical to the success of your garden.
Mechanical Controls
One of the primary ways nematodes are introduced to an area is through contaminated soil on boots, hands, crates, tools, and machinery. This means that any equipment or items that come into contact with infested soil can inadvertently transport beet cyst nematodes to uninfected areas, creating new problems in previously healthy gardens.
It is crucial to implement strict hygiene practices, such as thoroughly cleaning tools and equipment after use, avoiding the transfer of soil from one location to another, and ensuring that footwear is free of dirt and debris before entering clean areas. By being vigilant and adopting these practices, gardeners can significantly reduce the risk of nematode infestation and promote a healthier growing environment for their plants.
Cultural Controls
Beet cyst nematodes slow down in colder weather. Seeing as the majority of crops affected are cold weather crops, planting them in cooler weather may help with dealing with the rate of infection.
Weeds can provide a really great source of food for beet cyst nematodes. These nematodes thrive in environments where there is an abundance of host plants, including various types of weeds that may be present in your garden. Therefore, it is essential to maintain a weed-free garden to effectively manage and mitigate the risk of nematode infestations. By regularly removing weeds, you not only eliminate their potential as a food source for these pests but also disrupt their life cycle, which can significantly help in reducing the buildup of nematode populations. This proactive approach can lead to healthier soil and better crop yields, as fewer nematodes mean less root damage and improved nutrient uptake for your plants.
Enhancing Root Resilience Through Soil Health
Microorganisms like bacteria and fungi form a protective barrier around plant roots, creating a layer that combats harmful pests such as cyst nematodes while strengthening the plants' natural defenses. Prioritizing soil health is crucial for cultivating a resilient garden that can resist pest challenges. Healthy soil is rich in organic matter and teeming with beneficial microorganisms, which boost plant vitality. By enhancing your soil with beneficial biology, you support nature's defense force in protecting your plants and reducing their vulnerability to pest damage.
Ultimately, by prioritizing soil health and fostering a diverse ecosystem filled with natural predators, you can create an environment where beet cyst nematodes are kept under control if not eliminated.
On top of that, keeping your soil in good shape by testing it regularly and making adjustments can help keep nutrient levels just right, so your plants have good microorganisms so they get what they need to grow. Using the right compost, compost teas, and compost extracts feeds the soil and boosts microbial activity, all of which are key for nutrient cycling. This all-around gardening approach not only helps tackle the issues with cyst nematodes but also creates a sustainable setup that can lead to bigger harvests and better quality food.
At Old Oak Homestead, we like to create an environment where our soil is full of beneficial bacteria and fungi to tackle those pesky bugs in what ever form they come in. Just remember, nature knows how to keep things balanced, and with a bit of effort and care, you can grow a flourishing garden that keeps pests at bay and makes gardening more enjoyable.
Happy Gardening!
References:
Pires, D.; Vicente, C.S.L.; Menéndez, E.; Faria, J.M.S.; Rusinque, L.; Camacho, M.J.; Inácio, M.L. The Fight against Plant-Parasitic Nematodes: Current Status of Bacterial and Fungal
Biocontrol Agents. Pathogens 2022, 11, 1178. https://doi.org/10.3390/pathogens11101178
Fungal species naturally suppresses cyst nematodes responsible for major sugar beet
losses (2020, October 29) retrieved 17 February 2025 from
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