Control Methods and Key Technical Points for the Peach Borer
The peach borer, also known as the peach fruit borer, peach fruit worm, peach borer worm, etc. It belongs to the order Lepidoptera, family Pyralidae.
1. Morphological characteristics: The adult is about 12 mm long, with a wingspan of 22-25 mm, orange-yellow, with more than 20 black spots on the forewings and more than 10 on the hindwings. The eggs are oval, initially milky white, turning reddish-brown before hatching. The larva is 22 mm long, with a dark brown head and neck, a pale red back, and several pale brown spots on each body segment. The pupa is about 13 mm long, brown, with 6 curled anal spines at the end of the abdomen.
2. Damage symptoms: The larvae bore into and feed on the fruit. Eggs are laid between two fruits or at the junction of fruit and leaf. After hatching, the larvae bore into the fruit from the shoulder of the fruit or the junction of two fruits. One fruit may be infested by 1-2 larvae, and in severe cases by as many as 8-9. The larvae have the habit of moving from fruit to fruit to feed. The infested fruit exudes a yellow-brown transparent gum from the bore hole, and excrement sticks around the bore hole. When the damage is severe, it is commonly known as "ten peaches, nine bored," causing fruit drop and reduced yield.
3. Occurrence pattern: In southern China, 4-5 generations can occur per year, while in the north 2-3 generations occur. It overwinters as mature larvae spinning cocoons in the remains of various plants such as sunflower heads, stalks, or corn and sorghum. Pupation occurs in April of the following year, with the pupal stage lasting about 8 days, and adults emerge in May. Thereafter, one generation occurs in late June, early August, and from early September to early to mid-October (in the south). Subsequently, the larvae begin to overwinter one after another. If corn, sorghum, sunflowers, and other crops are present near the peach orchard, it can transfer and cause damage from the second generation onward. The larval stage lasts 15-20 days. After maturing, the larvae spin cocoons between fruits and between fruits and branches. The pupal stage lasts about 8 days before adults emerge. Adults lay eggs between fruits and between fruits and leaves, and may also move to sunflower heads or sorghum ears to lay eggs. The egg stage lasts about 6-8 days, and after hatching the larvae continue to cause damage.
4. Control methods.
In winter, treat the stalks of sunflowers, corn, sorghum, and other crops to eliminate overwintering adults. Before the emergence of the overwintering generation (first generation) adults, bag the fruit in time to protect it. Spray pesticide 1-2 times during each adult emergence and egg-laying period. Using 20% fenvalerate emulsifiable concentrate at 3000 times dilution, or 50% fenitrothion emulsion at 1000 times dilution, or 2.5% deltamethrin at 5000 times dilution can all achieve good control results.