Bamboo plants are beautiful and interesting. They provide us with many benefits such as food, shelter, medicine, and beauty. However, they are susceptible to various types of damage caused by insects and fungi. For example, white fungus is one of the most common bamboo diseases affecting bamboo plants. White fungus causes the death of the leaves of affected trees and shrubs; it may cause death or severe injury to young shoots if not treated promptly.
White fungus is caused by several species of fungi, but the most prevalent ones are the white rust fungus (Fusarium oxysporum) and the white pine bark spot (Pseudotsuga menziesii). These two fungi infect different parts of the plant. Fungi grow on infected wood and produce spores which fall off when they die. Spores then germinate in soil where they develop into new fungal growths called mycelia. Mycelia can grow anywhere on the plant, but are usually found near dead areas.
When these mycelia become large enough, they reach out and touch healthy tissue. If this contact occurs frequently over time, the fungus will eventually kill the healthy tissue.
The fungus grows best at temperatures between 60° and 80°F (16–26°C), but it is able to survive even lower temperatures. White fungus does not usually kill healthy plants, but it can severely weaken them. If the plant is already in a weakened condition, such as from drought, it may succumb to the infection.
Cultural Controls for Bamboo Plant Diseases
To prevent or reduce white fungal growth on your plants, try any or all of these cultural controls:
Give the plant adequate water. This helps minimize stress and reduces the chances of disease.
When pruning remove all diseased branches and dispose of them. Do not place them near other plants.
Soil should be well drained to prevent disease. Always keep the surrounding soil free of debris that may harbor disease organisms and water.
Avoid wounding the plants since wounds are susceptible to infection.
If possible, keep plant free of insects which may vector fungal infection. If they are present on your plants, keep insect population under control with recommended pesticides.
Always buy disease-free plants and plant only in well-drained soil.
Apply a fungicide approved for use on the type of plant you are treating. Follow all label directions for the proper amount of times to apply it.
Of course, if you’ve been following everything listed above, chances are you won’t have to worry about any fungal diseases anyway!
Bacterial Leaf Blight of Bamboo
Green and purple bacterial leaf blight (Pseudomonas sp.) is a common disease of running bamboo in the Southeast. This bacterium attacks the leaves and spreads to other parts of the plant when conditions are favorable. These favorable conditions are lots of moisture, warm days, and cool nights. Favorable conditions are common in early spring when many bamboo growers apply water after a dry winter.
Control of Bacterial Leaf Blight
Once this disease infects your plants, it can be very difficult to stop. Some fungicides may give limited control if applied repeatedly when conditions are favorable. However, removal and replacement with different stock is the best approach since once your plants are infected they likely will always be infected.
Whiptail (MAM 2007) is a disease that is fungal-like in nature and attacks the rhizome of your plants. This disease has been found in only a few states, including Arkansas, Kansas, Missouri, Oklahoma, and Tennessee. It has not been determined how this disease is spread but it is probably either through infected planting material or through the soil.
Whiptail is a little harder to detect since it slowly kills the plant over an extended period of time. Weak plants are probably most susceptible to this disease. The leaves will yellow and begin to die. The plant itself will also begin to deteriorate and lose its firmness. If you gently pull on the culm, it will be soft in some areas.
If you cut the culm, a black discoloration may be visible at the center of the plant.
Control of Whiptail
Unfortunately, this is a disease that cannot be controlled. All you can do once your plants become infected is to remove and replace them. Since whiptail has only been found in a few states and since there are so many species and varieties of running bamboos, it is unlikely you will ever have this disease. However, if you do suspect your plants are infected, have them tested since there are other diseases that will cause the same symptoms.
Rust (MAM 2007) is a fungal disease that attacks the leaves of your running bamboos. It is usually spread from plant to plant by wind or rain. This disease is more of a problem in warmer climates but it can also become a problem in the Southeast if the conditions are right. This disease is more of a problem on Clidemia, Hibanobambusa, and Thamnocalamus than it is on some of the larger timber bamboos.
Control of Rust
Once your plants become infected with rust it is too late for control. Your best defense against this disease is to buy resistant stock and plant in areas that have good air flow. Also, avoid damp, shaded areas since these are most favorable to the spread of this disease.
White Root Rot (MAM 2007) has been found in Arkansas, Kansas, Missouri, and Oklahoma. This disease is most common in clay soils but will occur in any type of soil if the conditions are right. It is a fungal disease that attacks the vascular system of your plants and cuts off the flow of water and nutrients. This results in a slow wilting of the leaves followed by wilting of the entire plant.
Control of White Root Rot
This disease is very difficult to control once it becomes established in your planting area. The best you can do is to try and reduce the amount of inoculum (infected material) available by removing and destroying all dead or dying plants, removing all plant debris, and avoiding planting in recently cultivated ground. If your plants show any signs of this disease, you should immediately remove and destroy them. Your best defense is to buy resistant stock.
Crown Rot (MAM 2007) is a serious problem only in Arkansas, Missouri, and Oklahoma. This disease is caused by a type of fungus that attacks the base of the culm or the root of the plant. Crown rot will initially cause a darkening and softening of the tissue at the base of the stem. As the disease progresses this area will turn black and may become mushy to the touch.
Sources & references used in this article:
The book of bamboo: a comprehensive guide to this remarkable plant, its uses, and its history. by D Farrelly – 1996 – cabdirect.org
Bamboo: A rich source of natural antioxidants and its applications in the food and pharmaceutical industry by C Nirmala, MS Bisht, HK Bajwa, O Santosh – Trends in Food Science & …, 2018 – Elsevier
Effects of ethylene and 1-methylcyclopropene (1-MCP) on lignification of postharvest bamboo shoot by Z Luo, X Xu, Z Cai, B Yan – Food Chemistry, 2007 – Elsevier