What You Need To Know About Nematodes

Nematodes are responsible for injured root tips, galls, root knots, leaf galls, excessive branching of roots, dying tissue, and distorted leaves.


What comes to your mind when you think of a nematode? For many people, these are parasites that feed on living plants and carry disease-causing microbes capable of infecting animals and humans.

But did you know that there are beneficial nematodes too? Neither nematode should be confused for the other. In addition to this, there are dozens of ways in which you can prevent parasitic nematodes from infesting your garden.

The largest population of nematodes aren’t parasitic. The few parasitic nematodes have an unsegmented and translucent body measuring about 1/50 inches long. These worms are responsible for injured root tips, galls, root knots, leaf galls, excessive branching of roots, dying tissue, and distorted leaves. These parasites are known to attack the roots of peppers, potatoes, cherry tomatoes, corn, lettuce, and carrots. Some plants such as alfalfa, rye, chrysanthemums, and onions are however capable of withstanding stem and leaf damage from these parasites.

Understanding Nematodes

Although commonly referred to as roundworms, nematodes aren't exactly true worms. Nematodes are multicellular insects with unsegmented, smooth bodies. Parasitic nematodes have a long and slender, or pear-shaped body and can only be seen under a microscope. These shouldn’t also be confused with filarial nematodes known to spread disease or infect the human body causing a weak immune system.

Soil-dwelling nematodes are known to feed on plants by either burrowing into the tissue or the surface. Some of these may cause damage to plant stems, roots, flowers, and foliage.

Although tiny, parasitic worms cause severe damage to crops. They puncture cell wall to suck plant nutrients and the cell contents. Some of the visible signs of a parasitic attack on plants include distorted growth, swelling, and dead parts of the plant. These nematodes may inject bacteria and viruses in the plan inflicting more damage to your plant crops.

Beneficial nematodes, on the other hand, help enrich the soil by feeding on other nematodes, insects, and decaying material. This releases nutrients to the soil.

Signs Of Nematode Infestation

Parasitic nematodes do not produce any specific side effects to the plants. Most of the symptoms you see are caused by other factors, including bacteria and virus infections, nutrient deficiencies, and air pollution. Surface nematodes may cause discoloration or twisted stems, flowers, and leaves. These nematodes may also target the roots feeding on them. The most common signs of infested roots include stunted plant growth, wilting, yellowed leaves, and poor yields. Lifting one of the infected plants from the soil, then washing the roots carefully can help you see signs of infection. The common ones are root rot, injured root tips, small lesions, and excessive root branching.

How Nematodes Spread

Nematodes thrive well in moist soil. Although they might not be capable of getting far on their own, they can use other mediums such as moist soil or water to navigate. Ensuring your soil is well-drained might help prevent an infestation. Anything that comes into contact with infected soil may also help spread these parasitic insects. Boots, gardening tools, animals, and the infected plants are the most common mediums.

Beneficial Nematodes

Beneficial nematodes have a characteristic translucent, unsegmented, slender, and long body measuring around 1/25 inches. These organisms play various roles in the garden. They help break down organic matter in compost piles, e.g. ¼ inch long decomposers.

They also come in handy in fighting most garden pests including cutworms, chinch bugs, clearwing borers, weevils, and white grubs. These nematodes will either inject deadly bacterial to the pests, enter the host, and even feed on it from the inside. You however need to purchase the right species of nematodes for various needs. You can invest in decomposers or those that help fight other deadly pests from the garden. As mentioned earlier, all nematodes thrive well in humid and moist conditions. Apply them well on your garden and ensure it remains wet for the best results. Be sure to water the garden regularly to keep the beneficial nematodes alive. experts recommend watering early in the morning to allow water to seep deep into the soil.




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