How to effectively prevent and control banana bunchy top disease

Bananas grow in tropical regions, where the growing period is often hot and humid, so many diseases occur. Because pathogens like this kind of living environment, among the many diseases, what fruit growers fear most is bunchy top disease, because this disease is called the incurable disease of bananas, and you can imagine how serious the damage this disease can cause to bananas. Today I will introduce this disease to everyone, so that if you encounter this situation you will be able to deal with it.

I. Causes of the disease

This disease is caused by infection with banana bunchy top virus, and it is mainly spread by piercing-sucking pests such as aphids, which transmit the virus. Soil and farming operations do not carry the virus. A species of banana aphid, Pentalonia nigronervosa, is the main vector. After the aphid feeds on a diseased plant, the virus can survive for about 13 hours, and during this time if it pierces and feeds on a healthy plant, it can still cause infection. After infection, the virus remains parasitic in the plant body.

II. Symptoms of the disease

In the early stage, just after the disease appears, the leaves become hard and brittle and break easily, the leaves are upright and narrow and long, the lengths of the midrib and petiole are inconsistent, and green veins begin to appear, a kind of green stripe. If infection occurs after shooting, the symptoms are normal leaves, but the petioles are thin and curved and no flower buds are produced or it is difficult to produce flower buds, affecting banana formation, with few or no bananas set, and the fruit is very small, crisp, and without aroma.

III. Prevention and control methods

1. Seed selection and seedling raising

Choose and buy disease-free seedlings, do a good job of quarantine when purchasing, and only buy and plant them after passing quarantine; or select and cultivate your own virus-free, disease-free seedlings.

2. Dig out diseased plants and prevent aphids

Once a diseased plant is found and you are not confident you can cure it, dig out the diseased plant at once, take it out of the orchard and burn it; or inject 10-15 ml of glyphosate stock solution or a liquid preparation made at 80% to kill the infected banana plant, dig out the plant, and also dig out all the soil under the diseased plant, spread quicklime for disinfection, expose it to the sun for one month, then replace it with clean soil. Replace with clean, disease-free soil. In order to control the spread of the disease, you can use 10% imidacloprid wettable powder or 3% acetamiprid emulsifiable concentrate at 800-1000 times dilution for spraying in the early stage to control aphids and prevent aphids from further transmitting the virus.

3. Spraying

In the early stage of the disease, use Shudingzhi with white vinegar dissolved in water at 1000 times dilution, 300 grams of liquid per plant (about half a spoonful), slowly drip-irrigating from the top center downward and injecting it into the banana stem for treatment; you can also add 20% Haopu aqueous solution at 500 times dilution, or 3.95 Bingdubike wettable powder at 600 times dilution and other antiviral agents for combined control. It will improve after about ten days. Spray once every 10 days for three or four consecutive times, safe and effective. If the outbreak is severe, it can only be dug out and removed.

4. Control fertilizer and water

Fertilization should follow the most suitable NPK ratio for bananas of 1:0.22:3.28. Spray Shudingzhi once a month combined with root drenching of paclobutrazol to prevent the disease together. In March, apply a topdressing of compound fertilizer once combined with zinc and boron fertilizers by furrow application. Apply two jin per plant, and at other times supply water and fertilizer normally to meet needs and maintain good tree vigor.

Banana bunchy top disease is the most serious disease of bananas, said to be an incurable disease, but in the early stage of the disease, it can still be controlled and improved, so the key to this disease is prevention, and prevention can solve most of the problems, but if aphids cause damage and the disease occurs, in the early stage you must quickly control the aphids and spray, and then there will be no problem.