Avocado pests and diseases and their control methods

Avocado Anthracnose

The dangers of anthrax

It will harm mature avocados, and will also attack leaves, twigs, flowers and young fruits, causing fruit drop and fruit rot. The disease usually occurs after the fruit is ripe. The initial lesions are very small, round, slightly concave, and brown or black in color. As the lesions expand, the depressions become more obvious and the lesions appear cracked. Eventually, the lesions develop into large areas with pink conidia appearing on the lesions. The pathogen can also invade the ripe flesh, causing the fruit to dry out and rot, and turn black-green in color.

Anthracnose control

The diseased branches and leaves must be removed to eliminate the source of infection, and the picked fruits must be treated with low temperatures.

Avocado scab

The harm of scab

The fruits infected with scab will initially have inconspicuous round brown scar-like protrusions, which will later turn into light purple. When the fruit is ripe, the spots will unite into one piece, the center will become sunken, and the skin will become rough. Scab does not affect the flavor quality of the fruit, but it will affect the appearance of the fruit.

Prevention and treatment of scab

Cut off the diseased branches and spray Bordeaux mixture or other copper preparations to prevent scab.

Cercospora spot

The harm of Cercospora spot disease

This disease can harm leaves, stems, and fruits, forming dead spots on the surface of the fruit or causing the epidermis to crack, and forming dead spots on the surface of the leaves with irregular shapes.

Prevention and control of Cercospora spot disease

Chemical methods can be used for prevention and control, such as spraying copper preparations or myclobutanil on branches and fruits.

Avocado pit rot

The harm of small hole fruit rot

This disease is very obvious during the ripening process of the fruit after it is harvested and softened. In the early stage, there will be some small and irregular spots on the skin, the flesh will have brown stripes, and then purple-brown irregular spots will appear on the fruit stalk. As the fruit matures, the area of the lesions will become larger and larger, the peel will be covered with mycelium and spores, and brown flesh and juice will flow out, with a very unpleasant smell.

Prevention and control of small hole shell fruit rot

Prune off diseased and dead branches, remove dead wood and diseased fruits, and eliminate the source of infection. When picking fruit, choose sunny weather to supplement and strengthen the nutrition of the fruit trees and reduce the occurrence of other diseases.

Avocado stem rot

Harm of stem rot

The first part to be infected is the fruit stem. As the fruit matures, the bacteria will invade the fruit. A very obvious black rotten area will appear with the stem as the center, and later it will spread to the entire surface of the fruit. After the bacteria invade the flesh, the fruit will emit an unpleasant odor.

Stem rot prevention and treatment

Clear the source of infection promptly, water the lower parts of the orchard to prevent the pathogen from moving to the fruits higher up, cover the fruit trees with film or weeds to promote the decomposition of diseased residues, and be careful not to harvest the fruit on rainy days.

Avocado Phytophthora Fruit Rot

The harm of Phytophthora fruit rot

It can cause fruit rot before or after the fruit is picked, and can also cause stem rot. Fruits infected with this disease will develop black circular spots near the stem, and the flesh will also be invaded by the bacteria.

Prevention and control of Phytophthora fruit rot

Prune off diseased dead branches and stems, clean up fallen and diseased fruits in the orchard, and cover the fruit trees with thick mulch to inhibit the spread of pathogens in the soil.

Avocado sooty disease

The harm of soot disease

Large amounts of black, sooty hyphae and spores will appear on the surface of fruits, leaves, and stems, and will also grow on the honeydew secreted by whiteflies.