Common Pests and Diseases of Chestnut and the Latest Control Methods

Chestnut is a fairly well-known nut tree species in China, providing substantial economic benefits for farmers in mountainous areas of China, and is one of the pillar fruit trees. Although the economic benefits are relatively high, it is threatened by many pests and diseases during the growing process, which seriously affect the growth of chestnut. In severe cases, it can even kill the trees and destroy the orchard, causing incalculable losses to the economic interests of farmers in mountainous areas. So what kinds of pests and diseases can affect chestnut? How should they be controlled? Let's take a look below!

1. Chestnut blight

Symptoms: Chestnut blight, also known as chestnut bark canker, mainly damages the trunk and main branches of chestnut trees. After a chestnut tree is infected with blight, the branches gradually lose their green color, and yellow-brown patches appear on the bark, continuously spreading and developing until they surround the entire trunk, generally expanding upward and downward, causing the bark to split, and the leaves also gradually turn brown and die.

Control methods: When selecting seeds, strictly follow quarantine regulations and do not choose seedlings or seeds from diseased areas. Strengthen soil fertilizer and water management, enhance the tree vigor of chestnut, carry out timely pest control and heat preservation, and improve the disease resistance of chestnut. Promptly treat various wounds on the tree body, especially the gaps at grafted areas, which should be coated with agents such as Bordeaux mixture. Diseased plants and diseased branches should be dealt with promptly and burned in a centralized manner.

2. Chestnut anthracnose

Symptoms: Anthracnose can harm any part of a chestnut tree. Diseased buds show brown rot, and leaves develop irregular brown patches with reddish-brown edges. Twigs form irregular dark brown sunken patches and eventually die. After the branches are affected, they are initially relatively smooth and develop circular black patches, and are easily broken by wind. Affected fruit begins to produce gray-white mycelium from the tip, develops dark brown lesions, and finally dies and falls off.

Control methods: First, after winter harvest is completed, carry out winter pruning, cut off all diseased and dead branches, then burn them in a centralized manner, clean the orchard thoroughly, and disinfect it comprehensively; a multi-sulfur suspension agent can be sprayed for disinfection. Spray an appropriate amount of agent before sprouting for prevention. Do not harvest too early at harvest time. Also, during the harvest and storage periods, take care not to injure the fruit, reducing conditions for pathogen invasion. Do a good job in cultivation management and timely pest and disease control.

3. Peach fruit borer

Damage symptoms: The peach fruit borer is a relatively common insect pest of chestnut. It occurs three times a year, and the period when it is most harmful to chestnut is from August to September. At harvest time, a large number of larvae are attached to the chestnut burrs. These larvae bore back and forth between the involucre and young fruit, hollowing out the fruit, making the chestnut lose its edible value; moreover, it should not be piled up for too long, as piling for more than half a month is the peak period of larval damage.

Control methods: When adults hatch the third generation of larvae on chestnut trees, spray agents such as fenitrothion and deltamethrin to kill them; sunflowers can also be planted in the orchard to trap and kill them. Then, before winter begins, clean up all empty chestnut burrs, sunflowers and other such materials piled together, burn them in a centralized manner, disinfect the orchard, clean up overwintering sites, and eliminate overwintering larvae.

The three above are the pests and diseases that frequently occur on chestnut. When using pesticides for control, reasonable control should also be carried out according to the actual local planting conditions. The pests and diseases that pose the greatest threat to chestnut yield should be taken as the main control targets. Prevention should also be carried out, checking potential pests and diseases as secondary control targets, inspecting specific diseases, and applying the right remedy, and pesticides must not be used blindly, otherwise the result will be counterproductive.