Be Careful - Similar Diseases Can Confuse the Diagnosis
Confused? Do Not Rush to Diagnosis - Avoid Confusion With Other Diseases or the Natural Growth Habit of Native Hawaiian Bananas
Cucumber Mosaic Cucumovirus (CMV) Native Plants may have morphology or growth habit resembling symptoms of BBTD. Please do not destroy these plants.
Disease name: mosaic

Pathogen: virus (CMV) transmitted by aphid or through cuttings

Symptoms: mottling and mosaic of leaves and flowers.

CMV has a very wide host range and is commonly found in weeds at farms. Damage to banana in Hawaii is considered not significant. It does not spread very rapidly in banana plantations in Hawaii and does not cause extensive damage to banana. However, diseased plants should be removed. This disease can also be detected by ELISA.

CMV Flower mottling and streaking (below). The symptom resembles BBTD mottling .

Below is polapola, a native Hawaiian banana variety with an unusual fruiting habit. The fruit stalk does not bend over toward the grouid. Fruits are borne sticking straight up in the air. This should not be confused with unusual fruit symptoms of BBTD.

Banana leaves with CMV have green streaks and leaves are wavy, but there is no "Morse code"
CMV on banana

The disease name, banana mosaic, derived from this symptom
Nutrient deficiencies in banana plants can mimic virus disease (below)

Banana plant with a probable calcium or boron deficiency
Left : a severe calcium or boron deficiency can occur when plants outgrow their calcium or boron supply. This can result in deformed, bunchy and yellow leaves at the center/top of the plant and may resmeble bunchy top.

The plant at left does not have BBTD, it probably has a calcium or boron deficiency that can be corrected by adding a caclium or boron fertilizer.

To confirm that this plant does not have BBTD, one would check closely for other symptoms such as Morse code, green J-hooks, and petiole streaking to confirm whether or not this plant has bunchy top disease.
Photographs are courtesy of the University of Hawaii and the Hawaii Department of Agriculture

Maintained by Scot Nelson:
Last Revised on September 12, 2006