The red-necked celestial bull is also known as the peach-necked celestial bull, the red-necked celestial bull, the iron cannon worm, and the ha worm. It belongs to coleoptera, Apocynaceae. It is mainly harmful to cherries, peaches, plums, apricots, etc., and is the main pest of the branches of stone fruit trees.
First, the morphological characteristics of the red-necked celestial bull
1. Adult insects. The body is 26 to 37 mm long, the body is black and shiny, the back of the thorax is red, there is a thorn-like protrusion on each side of the border, and there are 4 tumors on the back. The antennae are filamentous and bluish-purple , with smooth elytra wings , a base wider than the thorax , and a tapering end.
2. Larvae. The body of the mature larvae is 40 to 50 mm long, milky white, and yellowish white when it is nearly mature. The anterior thorax is broad, with 4 yellow-brown patches in the anterior half of the dorsal plate of the anterior thorax.
3. Eggs. Oblong oval, 6 to 7 mm long, milky white.
4. Pupae. It is 25 to 36 mm long, yellowish-white, dark brown when nearly feathered, and has one protrusion on each side of the thorax and the center of the leading edge.
Second, the red-necked sky bull is harmful symptoms
The larvae feed on the branches of the tree, and the feces are blocked with insect passages, and some excrete a large amount of feces from the fecal holes and accumulate at the base of the trunk, and some feces are squeezed out of the skin cracks, and glue often occurs. The branches that are eaten by the moth are easy to cause glue, weaken the tree, and when the damage is serious, it can cause dead branches or dead trees, and even destroy the whole garden.
Third, the occurrence of red-necked celestial bulls
In the north, 1 generation occurs in 2 to 3 years, and the larvae overwinter twice in the trunk moth. Overwintering larvae begin to feed when the cherry sprouts in the spring. In Shandong, adults occur from early July to mid-August, and in Beijing, adults occur from mid-July to mid-August. Adults have poor flight ability and often rest on branches at noon on sunny days. Adults lay their eggs at the cracks in the epidermis of the main trunk and main branches within about 1.2 m of the surface, of which the most eggs are laid on the trunk of the tree about 35 cm from the ground.
The cortex at the spawning site is raised and lobed, with an "L" or "T" shaped wound with foamy glue flowing out, which is easy to identify. At the egg stage of 8 to 10 days, the hatched larvae are directly mothed under the skin, and the first and second instars are completed in that year, and the third-instar larvae overwinter in the worm trough between the phloem and the xylem. In the spring of the following year, activities began to be active again, drilling moths into the xylem and discharging large amounts of sawdust manure outside the borer holes, accumulating at the base of the trunk. When the larvae moth into the xylem, they feed first towards the marrow and then downwards. After developing into a fifth-instar larvae, it overwinters in the worm tunnel or feathering chamber. From May to June of the third year, the diapause mature larvae stick to the worm dung and wood chips begin to pupate, pupate stage 20 to 25 days, and then feather out of adult worms.
Fourth, the red-necked natural cattle prevention and control methods
1. Artificial prevention and control. The trunk is frequently inspected to find fresh insect droppings and the larvae are dug out with a knife; the adults (late June to mid-July) lie still on the trunk at noon and can be hunted artificially. During the growing season of fruit trees, worm holes are found and feces are hooked with wire, stuffed into cotton balls dipped in insecticides, and then the moth holes are blocked with mud. When the density of the worm mouth is large, the insecticide can be injected into the trunk with an injection needle, which can kill the larvae of the epidermis and xylem.
2. Paint the trunk white. Before the adults lay their eggs, spray the branches with whitening agent (1 part sulfur + 10 parts quicklime + 0.2 parts salt + 0.2 parts animal oil + 40 parts water) to prevent the adults from laying eggs.
3. Biological control. Insect pathogen nematode fluid is perfused into the borer hole with a syringe to parasitize tianniu larvae, or to release guanshi swollen leg wasps in the field. In addition, the natural predators of the celestial bull also include velvet armor and woodpeckers, and attention should be paid to protection and artificial migration.
4. Pharmaceutical prevention and control. On the trunk and main branches within 1.5 m of the surface, starting one week after the peak of adult emergence (about mid-to-late July), spray the trunk with 800 times of chlorpyrifos emulsion, and spray it again once another time after 10 days to poison the hatching larvae. For the larvae deeper in the borer hole, the aluminum phosphide poison stick is stuffed into the borer hole, or the hole is injected with a syringe 80% dichlorvos emulsion or 40% chlorpyrifos emulsion 20 to 40 times the solution, and the orifice is closed with yellow mud. Due to the fumigation effect of the agent, the larvae in the hole can be killed.