Fusarium wilt is a widespread plant disease caused by the fungus known as fusarium oxysporum which inhabits the soil.
This type of fungal infestation is not specific to any one type of plant. Indeed, it affects hundreds of different plant species.
Fusarium wilt disease is a threat to a number of economically important food products such as solanaceous crops (nightshade family) and more. Some of these include:
- Sweet Potatoes
- Crisphead lettuce
- Jerusalem cherry (Solanum pseudocapsicum)
- Watermelons and other crops under melon family
- Banana trees
The fusarium wilt of bananas is commonly known as Panama disease. It also affects some palm tree cultivars such as:
- Canary island date palm (Phoenix canariensis)
- Queen palm or cocos palm (Syagrus romanzoffianna)
- Date palm (Phoenix dactylifera)
Fusarium Wilt Causes General Plant Distress
This type of fungus thrives at warm temperatures (75° degrees Fahrenheit). It is a long-lived fungus that can stay in the soil indefinitely (see chlamydospores) even when no host plants are present.
When plants become infected, they generally experience stunted growth.
Plants may start out with healthy dark green leaves, but as the infection progresses the leaves become pale, wilt, wither, and die.
As they die, the lower leaves of the diseased plants begin to drop off and the symptoms move progressively to the upper leaves.
This fungal infection affects the vascular tissue of the roots and stems, and creates dark streaks in both.
This causes lower stem vascular tissue decay and root rot, which can kill seedlings rapidly.
Avoid Spreading Fusarium Wilt
Because of the prevalence of this pathogen, it is very important to practice good garden hygiene to prevent its spread. Begin by keeping your gardening tools clean between uses.
Additionally, when you plant seed be certain that it is clean and has not been taken from plants that have been infected. Make it a point to always look for resistant varieties to this ubiquitous infection.
It is also possible to gain some measure of control of the fungus through the use of soil fungicides.
It’s important to understand that most types of fungus are very handy at developing resistance against these fungicides, though. For this reason, it is best to be very diligent in use of preventative measures.
Fusarium species can remain dormant in old soil and plant debris indefinitely, so it is very important to sterilize all plant equipment between uses. Use a bleach solution to clean pots and gardening implements. Always use new soil when potting plants.
You should also remember to wash off your gardening shoes to prevent tracking the fungus from place to place.
Gather all plant debris at the end of every growing season and dispose of it properly.
If you believe that the debris is infected with the fusarium fungi, you should burn it. Be especially careful not to compost any infected plant waste.
Practice crop rotation in your flowerbeds and garden to continue challenging the fungus with new types of plants.
In an area that is especially infested, you may want to try soil solarization by covering the area with black plastic to superheat and raise the soil temperatures to kill off the fungus. It is important that this area be exposed to full sun for maximum heat.
It is essential that you control this fungus in greenhouse and crop settings. If left unchecked, it can definitely overtake great swaths of land and affect most types of plants.
Tomatoes & Their Kin Are Especially Susceptible
This fungal disease is particularly threatening to plants belonging to the nightshade family. Among these are peppers and tomatoes. Fusarium does its dirty work by entering the plant’s roots.
It blocks vessels found within the cells and prevents the plant from being able to transport nutrients and water throughout.
These symptoms seem to be worse during the day when the sun is out, and plants can give their caregivers some false hope by seeming to recover overnight; however with the rising of the sun, the symptoms will also rise.
Eliminate Affected Plants In Your Yard & Garden
Fusarium wilt does not always kill plants. Sometimes it simply causes an ongoing, chronic failure to thrive. Plants that are experiencing the symptoms should be eliminated rather than treated.
Fusarium wilt is incredibly tenacious and extremely contagious, so it does not pay to take chances with it. When you suspect that your plants have been infected by this fungus, you should simply pull them out, treat the soil and start over.
While treating plants in your yard and garden is not advisable or desirable, you may wish to treat individual houseplants that have been infected by the fungus.
To do this, you will need to purchase a professional fumigant. You can find this at your local garden center or online. Be sure to read all instructions carefully and follow them closely.
These types of fungicides work by soaking the bulbs or roots of your potted plants. Generally speaking, to use this sort of solution you would remove the affected plant from its pot and gently clean the infected soil from the roots, tuber, corm, or bowl. Dispose of the soil properly and rinse the plant thoroughly.
Next, you would place the plant in a bucket of the fungicidal solution prepared according to package directions. Once treatment is finished, repot using entirely new and clean soil and container.
Fighting Fusarium is an ongoing battle. You must never let your guard down.
Keep a close eye out for plants that have been infected and deal with them quickly and ruthlessly.
Keep your garden and gardening implements clean and dispose of infected plant debris promptly and properly.