Identification and Control of Tomato Fusarium Wilt and bacterial Wilt

Tomato wilt and bacterial wilt are very important diseases restricting tomato production in summer and autumn in our region, causing great losses to growers. In general, the identification of these two diseases is easy to confuse, the common symptom is wilting, but the two are different, so there are similarities and differences in prevention and control. The identification and control techniques of these two diseases are described as follows.

I. Distinction

1. Bacterial wilt disease is all-plant, seedlings do not show symptoms, but wilt disease can occur in seedlings. Bacterial wilt is the first wilting of the top leaves, while blight occurs: the leaves develop gradually from bottom to top.

2. The diseased leaves of bacterial wilt showed wilting and drooping, not fading green, while the diseased leaves of blight changed from green to yellow, and half of them died, while the other half was still alive.

3. Disease development speed is different, bacterial wilt development speed is faster only a few days will die. However, the slow development of blight takes about 15 to 30 days to die.

4. Bacterial wilt in wet weather, the disease will be cross-section of the stem extrusion, there is milky mucus overflow. In wet weather, pink mold grows at the base of the stem of Fusarium wilt, but not bacterial wilt.

5. Bacterial wilt is a bacterial disease while fusarium wilt is a fungal disease.

II. Prevention

1. Agricultural control measures for tomato bacterial wilt and fusarium wilt were basically the same.

(1) Selection of resistant varieties suitable for local planting is conducive to controlling the occurrence, development and spread of diseases. The tomato varieties Kangqing 19, Danfen 1, Fengbao, Hongkang 1, Xiaxing and L402 had better resistance to bacterial wilt. At present, there is no good resistant variety to Fusarium wilt, but grafting cultivation can be used to control the occurrence of this disease, grafting wild tomato CH-Z-26 as rootstock.

(2) It is necessary to strengthen the management of fields and greenhouses, plant in deep grooves and high ridges, avoid root injury and uneven dryness and wetness in the field; timely remove the residues in the field to avoid greater spread of pathogens.

(3) Applying enough basal fertilizer, preferably dry chicken manure compound fertilizer treated by high temperature, increasing phosphorus and potassium fertilizer, spraying foliar fertilizer such as Nonglebao and Opur for 2~3 times in growing period, is beneficial to improving plant resistance. Pay attention to underground pests and nematodes.

(4) The seriously diseased fields can be rotated with onions, garlic and cruciferous vegetables for 4~5 years.

2. pharmaceutical prophylaxis

(1) The seedlings of bacterial wilt are grown in soilless and new soil; root irrigation or root soaking is carried out when planting; root irrigation is carried out with 500 times solution of 77% can be killed before transplanting, or root soaking is carried out with 3000~4000 times solution of agricultural streptomycin sulfate for 1~2 hours.

(2) Fusarium wilt seedlings without soil, new soil or bed soil disinfection, each square meter of bed surface with 50% carbendazim wettable powder 8~10 grams, add 4~5 kilograms of fine soil mix well, first 1/3 of the soil on the bed surface, and then sow, and then cover the rest of the soil on the seeds; planting when the root irrigation or root soaking. 1~2 days before transplanting, root irrigation with 500 times of 50% carbendazim or root soaking with 500 times of 50% carbendazim for 1~2 hours.

3. chemical control

(1) Bacterial wilt When diseased plants are found in the field, they should be immediately removed and burned, and the surrounding soil should be disinfected; Disinfect with 2% formalin solution or 20% lime water; In the early stage of disease, use 77% to kill 400 times solution or agricultural streptomycin sulfate 3000~4000 times, 25% ammonia copper 500 times for root irrigation, 300~500 grams per plant; Destroy seeds for more than 80% of diseased plants in the field and have no production and management value.

(2) Fusarium wilt When the diseased plants are found in the field, immediately pull them out and burn them, disinfect the surrounding soil; irrigate with 50% carbendazim 500 times or 70% thiophanate-methyl 500 times solution; irrigate the roots with 50% carbendazim 500 times or 70% thiophanate-methyl 500 times solution at the initial stage of disease, and irrigate each plant with 250 grams of solution; destroy the seeds of more than 80% diseased plants in the field and have no production value.