Hazelnut Pest and Disease Control Methods and Technical Key Points

Hazelnuts are one of the most common dried fruits in our daily lives, and they are also the dried fruit most often used for processing, such as liqueur-filled nut kernels and the like. Moreover, the hazelnut tree also has value as a fuelwood forest and is widely used for converting land suitable for afforestation, although the current scope of artificial cultivation is not yet very extensive. However, as the country places increasing emphasis on desert afforestation work, the role of the hazelnut tree is also growing. But when planting hazelnut trees, many pests and diseases are often encountered. So what pests and diseases affect hazelnut trees? How should they be dealt with? Let's take a look together!

1. Hazelnut Leaf Powdery Mildew

Symptoms: Hazelnut leaf powdery mildew, also known as hazelnut powdery mildew, or simply powdery mildew, generally occurs on hazelnut trees planted in Northeast China. Powdery mildew mainly damages the leaves, but it may also harm the twigs, young buds and husks. After a leaf is infected, unclear yellow patches appear on the leaf, and soon white powder appears at the patches; then the patches begin to slowly spread and expand, with many patches joining together into sheets. The leaf also gradually loses its green color, slowly turning yellow, twisting and scorching, and finally leading to early leaf drop. For young leaves, it mainly prevents them from unfolding, and white powder also appears on the twigs, accompanied by cracking.

Control methods: Once signs of the disease are found, the diseased branches and leaves of the affected plants should be removed immediately. If the affected plant is a central plant, it should be completely cut down in time to reduce the source of infection. Thin the branches appropriately to enhance air circulation and the tree's disease resistance, and spray triadimefon for prevention.

2. Scarab Beetles

Damage symptoms: Scarab beetles are the most common pests of all plants and belong to the pest family Scarabaeidae in the order Coleoptera. Those that harm hazelnut trees mainly include the Oriental scarab and the apple hairy scarab, among others. Adult scarab beetles gnaw on the tree's young leaves and foliage. Adults generally lay eggs in the soil; after the eggs hatch underground, the larvae begin to gnaw on the tree's roots, hindering the tree's absorption of nutrients and seriously affecting tree development.

Control methods: First, implement crop rotation and rotational grazing planting techniques; continuous cropping is not suitable. Select disease-resistant seeds, soak and disinfect the seeds before planting, use bagging techniques, plow and disinfect the soil, and create a mixed forest. You can also release an appropriate amount of Beauveria bassiana, attract soil wasps, and attract birds to bring in the natural enemies of scarab beetles. Scarab beetles have a death-feigning state, generally feigning death on the tree trunk, so you can shake the tree to make the scarab beetles fall off and carry out manual capture. Finally, chemical control with pesticides such as insecticides can also be used.

3. Hazelnut Weevil

Damage symptoms: The weevil mainly harms wild hazelnut forests. Although it occurs less often in artificially planted hazelnut forests, everyone still should not take it lightly. Adult weevils bore into and feed on young buds and leaf branches, causing the young buds to be incomplete, the leaves to be covered with pinhole-like holes, and the branches to be hollowed out and extremely easy to break, affecting the growth of new shoots. They also extend their slender snout into young fruit, causing the young fruit and young embryo to stop growing and developing, resulting in early fruit drop. They also excrete feces inside the fruit.

Control methods: During the supplemental feeding period before adult oviposition and the early stage of egg laying, use a high-concentration D-M mixture to poison and kill the adults. Then give the hazelnut forest a comprehensive treatment and disinfection, spraying about three times, with an interval of half a month each time.

The above are the pests and diseases that often appear when planting hazelnuts. Everyone must pay attention to the sanitation and disinfection of the orchard, as most causes of disease are brought about by improper orchard management. Although the incidence rate of hazelnuts is not high, this does not mean they will not develop diseases. Diseases deal a fatal blow to hazelnuts. If not dealt with in time, they will lead to a large reduction in hazelnut yield or even a total loss of harvest, causing incalculable losses to farmers.