How to control insects in the roots of fruit trees
Fruit trees are a common type of sapling in our country, but during cultivation, various pests and diseases can appear, and insects in the roots are one of them. So what should be done about insects in the roots of fruit trees?
1. What should be done about insects in the roots of fruit trees?
Insects in the roots of fruit trees are mostly root-knot nematodes. For every sq m, use 1 mL of 1.8% abamectin emulsifiable concentrate, dilute it 2000-3000 times, and then spray-irrigate the soil. Alternatively, outside the projection of the fruit tree canopy, dig a small hole 20 cm deep every 30 cm, then apply 2 kg per mu of “Shaxianhuang” granules mixed with fine sand at a ratio of 1:20. When applying, it can be combined with fertilizing the fruit trees by mixing the prepared medicated soil evenly with the fertilizer and applying it in holes, furrows, or in a radial pattern.
2. What are the symptoms of root-knot nematodes in the roots of fruit trees?
Swollen root nodules are the main symptom of this disease. Root-knot nematodes mainly harm the fine roots, branch roots, and fibrous roots of fruit trees, parasitizing between the root cortex and the central cylinder, causing excessive growth of root tissue and forming root nodules of varying sizes, initially milky white and later turning dark brown, making the root hairs sparse and small. In severe cases, old root nodules rot and the root system dies. Some nematodes can also harm the stems, leaves, flowers, and fruits of fruit trees.
1. Branches and trunk: branches are short and twigs are weak; in severe cases, the branches wither.
2. Leaves: leaf color turns yellow, lacks luster, leaf margins curl, showing a water-deficient appearance, and leaves also show symptoms such as nutrient-deficiency mosaic, and finally the leaves dry up and fall off.
3. Flowers and fruits: many flowers, few fruits, low fruit set rate, and small fruits.
3. How are root-knot nematodes spread?
Root-knot nematodes spread over a wide range and occur commonly in all provinces north of the Yangtze River, and are even more common in areas with slightly alkaline soil. In orchards they generally occur sporadically, and occasionally occur in patches. They are mainly spread through rainwater or soil, and infect through wounds.