A Detailed Explanation of the Symptoms and Control Measures of Banana Fusarium Wilt

Banana is a common tropical fruit with many varieties, and it is also one of the fruits we eat more of in our daily lives. Bananas are suitable for all ages, rich in certain nutrients, and inexpensive. When growing bananas, you should choose suitable varieties according to local conditions. If management is improper, fusarium wilt is very likely to occur. Let us take a look at the introduction to the symptoms and control measures of banana fusarium wilt.

I. Symptoms of Banana Fusarium Wilt

Banana fusarium wilt is also called Panama disease of banana and Fusarium wilt of banana. It has long occurred in many countries in Latin America, and was also discovered early in Taiwan, China. This disease is listed as a quarantine object for both foreign and domestic quarantine in China. From 1985 to 1988, in Zhongshan, Panyu, and Huadu in Guangdong Province and in the suburbs of Guangzhou, Longyajiao (Guoshanxiang) and Fenjiao suffered relatively large-scale outbreaks, with incidence rates generally 3.7%-26%, and in severe cases reaching 60%, causing devastating losses. At the initial stage of the disease, yellowing is seen at the leaf margins, and the diseased leaves wither rapidly and droop, turning from yellow to brown and then drying up. When the corm and roots of a diseased plant are cut longitudinally, the vascular bundles can be seen to be necrotic and turned yellowish-brown or purplish-red. This disease is a vascular bundle disease caused by Fusarium, and the pathogen is Fusarium oxysporum f. sp. cubense. Four physiological races have been discovered, among which race 4 has already been found in Taiwan, China and can infect all banana and plantain varieties, posing the greatest danger. The primary source of infection of this disease comes from diseased plants and contaminated soil. The thick-walled chlamydospores of the pathogen can survive in soil for several years to more than ten years, but their survival period is greatly shortened under conditions of waterlogging and lack of oxygen. Long-distance spread of the disease occurs mainly through seedlings, contaminated soil, and flowing water. Banana plantations in low-lying areas are prone to the disease.

II. Control Measures for Banana Fusarium Wilt

1. Choose banana varieties with good disease resistance

At present, disease-resistant breeding is the only fundamental way to control banana fusarium wilt. When varieties with relatively high resistance are invaded by the pathogenic factors of banana fusarium wilt, they can automatically form a defense mechanism within the plant, and through reasonable regulation of pathogenic factors and cellular genes, they prevent the banana plant from being infected, further enhancing the disease resistance of the banana plant. Generally, after a banana plant is infected by pathogenic factors, the content and types of proteins, free amino acids, and other substances inside it will undergo great changes, and this is directly related to the banana variety.

2. Crop rotation must be reasonable

In diseased areas, practice paddy-upland rotation to reduce the soil pathogen population. The banana fusarium wilt pathogen is a soil inhabitant and can survive in soil for 8-10 years, but under submerged conditions its survival time is greatly shortened. Practicing paddy-upland rotation is the most effective method for controlling banana fusarium wilt. Severely affected banana plantations can be rotated with sugarcane.

3. Promptly clear away banana seedlings that have already become diseased

In banana plantations where fusarium wilt occurs, diseased plants should be promptly dug out, dried in place, and burned. Where conditions permit, glyphosate solution can first be injected into the diseased banana plants (inject at a height of 15 cm on the plant, 10 ml for large plants and 3 ml for small seedlings). After the plants die, take the diseased plants outside the plantation in a unified manner and burn them in a centralized way or bury them deeply.

In banana plantations with sporadic disease, other non-banana crops must be planted instead or the land must be used for other purposes. In banana plantations in severely affected areas, lime or carbendazim and other agents should be used to disinfect the soil around the diseased plants, supplemented by agricultural control; the control effect of doing so will be very good.

4. Pay attention to later-stage management

When planting bananas, pay attention to increasing the application of organic fertilizer and biological bacterial fertilizer. Generally, before planting, apply 2 kg of Zhijingnong compound microbial bacterial fertilizer per plant as base fertilizer. During flower bud differentiation, apply Zhijingnong Bacillus subtilis water-soluble fertilizer at 400 times dilution per plant, pouring 20-30 jin per plant. Use organic fertilizer to improve the soil, use beneficial bacteria in biological bacterial fertilizer to suppress pathogens, and supply sufficient phosphorus, potassium, calcium, and magnesium fertilizers, so that the tree vigor is strong, which can enhance disease resistance and reduce disease occurrence.

During the growth and development of bananas, attention should also be paid to controlling underground pests. Zuantilong (abamectin-phoxim) can be used for drenching to effectively control various underground pests.

In addition, during the planting period, soil standing water should be drained in a timely manner. For slightly acidic soil, mature lime powder can be spread to neutralize soil acidity and eliminate the conditions for the survival, reproduction, and infection of pathogens.