Tropical yellow leaf disease type 4, also known as banana AIDS, has recently spread from Southeast Asia to Mozambique and Jordan. Banana AIDS will make the central part of the banana tree shrink and turn black, and all bananas in the banana garden will wither completely within 2 to 3 years.

history

As early as 1950, another type of yellow leaf disease broke out, which made the main banana variety "GrosMichel" almost extinct. Finally, scientists cultivated "Hua Jiao" as a substitute, which now accounts for 95% of the global banana exports, but like other varieties of bananas, it has no resistance to yellow leaf disease.

By 1990, yellow leaf disease broke out again in Malaysia and Indonesia, and many bananas were destroyed by the industry to prevent its spread. On 20 13, workers in Mozambique banana plantation found that some banana leaves turned yellow, and a few weeks later, banana trees began to fall down. Scientists later confirmed that bananas were infected with yellow leaf disease, and the authorities immediately destroyed the infected bananas, hoping to stop the spread of the epidemic. Professor Svenman, a banana expert at the University of Leuven, described that if yellow leaf disease spreads to Latin America, it will cause serious disasters, and its spreading speed will be as fast as forest fires.

harm

As one of the incurable diseases of human beings, AIDS is often daunting. Bananas are also infected with AIDS, and bananas in the world will face extinction. It is said that this disease called "banana AIDS" is called "Yellow Leaf Disease Tropical Type 4". Yellow leaf disease has always been considered as the enemy of bananas. Its fungi can lurk in the soil for more than 30 years and spread through water droplets and a small amount of soil attached to machines or shoes. Once the banana is infected with yellow leaf disease, water and nutrients cannot be transported in the tree, which makes the central part of the banana tree shrink and turn black, and all bananas in the banana garden can wither in two to three years.

affect

However, many large banana producers insist that the situation is under control. Fyffes, an Irish fruit distributor, said that he would pay close attention to the situation and said that the banana supply in the UK was not seriously threatened at present.

It is understood that bananas and plantains are the fourth largest staple crops in the world, second only to rice, wheat and millet. In 20 14 years, about 4 10/00000 people in developing countries consume as many as13 calories a day, and bananas are also their main source of income. Experts say that this irresistible virus may have spread to Latin America, which may eventually destroy as much as 85% of the world's banana production, and 465.438 billion people whose main food is bananas may go hungry.

Latin America is an important producing area of the main banana variety "cavendish". Up to 70% of local bananas are exported to all parts of the world, and the trade volume is as high as 5.4 billion pounds (about 55.6 billion yuan). The Food and Agriculture Organization of the United Nations (FAO) warned that yellow leaf disease will threaten banana industry, which will hit food safety, income level, employment situation and even government revenue in many tropical countries.

Prevention and treatment

(1) Plant quarantine: Banana Fusarium wilt is a famous quarantine object in the world. It is necessary to strictly control the transportation of banana seedlings in the ward. If you find a diseased plant, burn it immediately.

(2) Agricultural control:

① Selecting and planting disease-resistant varieties and disease-free seedlings.

② Strictly control the location of banana nursery. It is forbidden to set up a banana nursery near the fruit farm where the epidemic occurred, and the secondary banana nursery must be thousands of meters away from the place where banana yellow leaf disease occurred; It is advisable to choose a site with high terrain, which is not affected by irrigation water flow, has no disease records such as yellow leaf disease in the past, and is surrounded by perfect epidemic prevention and isolation facilities; Advocate the establishment of banana nurseries in mountainous areas. The site must be strictly accepted by the factory inspection organization before it is finalized. Banana orchards with serious diseases can rotate with sugarcane for 1 ~ 2 years.

(3) Chemical control: After the diseased plants are removed, lime or formalin is applied to the diseased site and the surrounding soil for disinfection. Spray with 70% thiophanate-methyl superfine wettable powder 1 0,000 times solution, or 50% benomyl wettable powder 1 0,500 times solution, or 500 times solution of 50% mixed sulfur suspension.

Note: the utilization data of tropical type 4 of yellow leaf disease is similar to that of banana wilt in Panama, and the classification basis is not clear. Banana AIDS has been reported as banana cancer. Although yellow leaf disease is resistant to fungicides, it can be controlled biologically. There are many varieties of banana resistant to yellow leaf disease, so don't worry too much.