Why is mango susceptible to anthracnose when it encounters low temperature and rainy weather? How to prevent it?

Anthracnose is one of the most common diseases of mango, which occurs in mango producing areas and the whole growth period.

In addition, anthrax spreads very fast. Continuous high humidity weather such as rain and fog is especially suitable for the outbreak and spread of anthrax.

Even orchards with high humidity, poor ventilation and small spacing between plants are more susceptible to infection.

Harm of anthrax

Anthracnose occurs at the flowering and fruit-setting stage, and the yield is reduced by 30-50% in severe cases; During storage and transportation, the rate of diseased fruits reaches 30-50%, and even serious cases will not occur! Anthracnose mainly harms young leaves, branches, inflorescences and fruits of mango.

1 Blade damaged

At the beginning of the disease, young leaves will appear discrete dark brown spots, which will gradually expand and merge, and finally form a large area of dead spots, and the leaves will shrink and deform, and then wither and fall off. In severe cases, the leaves will completely fall off and become bald branches.

2 harmful branches

When the lesion spread on the branches for a week, all the branches above the lesion died, and the spots grew out of small black particles.

Three. Harmful inflorescence

Infected inflorescences and flowers will gradually turn black, wither and fall off, and even cause flower diseases in severe cases!

4 Harm to fruits

Young fruits are prone to anthracnose, and the black spots on the peel will gradually expand as the fruit matures!

Black spots appear on the surface of mature fruit, and the center is sunken. After a large number of diseased spots heal, a large area of rough and cracked anthracnose spots often form on the fruit shoulder, or is it notorious along the fruit shoulder? Black tears? .

Preventive and control measures

1 Agriculture and Forestry Control

Anthrax is famous for its rapid spread. Timely treatment of disease residues in the park, centralized destruction; At the same time, pruning fruit trees properly, keeping ventilation and reducing the humidity of orchards can greatly reduce the probability of large-scale infection of anthracnose.

2 chemical control

In the above critical period, attention should be paid to prevention and drug selection to avoid invasive wounds caused by anthrax as bacterial keratosis.

If the average temperature at flowering, fruiting and young leaf stage is above 14℃, it is predicted that there will be continuous rainfall for more than 3 days in the future, that is, spraying pesticides before precipitation;

In mango orchards with high temperature and humidity, protective fungicides such as mancozeb 1 ~ 2 should be sprayed two days before flowering, after 80% flowers wither, in bud stage and young fruit stage. The film is attached to leaves or fruits, which protects plant tissues and is not easy to produce resistance;

If a disease center is found, early prevention and treatment can be carried out. At an appropriate time, you can use the correct dose and spray it twice to the serious illness center.

Precautions: Try to avoid taking medicine at noon to avoid damaging young leaves and peels. Alternate use of drugs to reduce drug resistance.

Other recommended drugs: tebuconazole, prochloraz, phenoxy methyl ester, tebuconazole? Azoxystrobin propiconazole? Azoxystrobin and others (note: prochloraz is very effective in the treatment of mango anthracnose, but some varieties (Taiya, Guifei, etc.) are very sensitive to fungicides and should be mixed with other pesticides to avoid phytotoxicity. It is recommended to try it out in a small area before spraying. )