Monochamus alternatus Hope, also known as Pine Ink Celestial Bull, belongs to the Coleoptera family and is an important dried insect pest of pine trees in our province.
1 Host, distribution and hazards
Pine brown sky cattle mainly harm masson pine, black pine, cedar and other pine trees. It has occurred in Huangshan, Xuancheng, Chizhou, Tongling, Ma'anshan, Hefei, Chuzhou, Anqing, Bengbu, Wuhu, Lu'an and Huainan regions in our province. Pine brown tianniu larvae drill into the branches of pine trees, causing pine tree death when the moth path surrounds the trunk. Pine brown tianniu is the most important vector of pine wood nematode disease, known as pine cancer.
2 Morphological characteristics
2.1 Adults
It is 15 to 28 mm long and orange-yellow to russet brown. The antennae are maroon, the male antennae are longer than the female, the male antennae are more than twice the body length, and the female is about one-third longer. The dorsal plate of the front thorax is matched by two broad orange-yellow longitudinal stripes and three black velvet stripes. The small shield is densely covered with orange-yellow fluff. Each elytra has 5 longitudinal stripes, consisting of square or rectangular black and off-white fuzz spots.
2.2 eggs
The eggs are about 4 mm long, milky white, and slightly sickle-shaped.
2.3 Larvae
Milky white, about 43 mm long when ripe. The head is dark brown , the dorsal plate of the forebreast is brown , and there are wavy transverse stripes in the center.
2.4 Pupae
Milky white, cylindrical, 20 to 26 mm long.
3 Biological characteristics
It occurs in 1 generation per year, and the old mature larvae overwinter in the worm tunnel. In late March of the following year, the larvae pupate pupae at the end of the worm passage and pupate in the internalized pupae, starting in mid-to-late April, with a peak period of mid-to-late June. In mid-April, the adults begin to feather, and after feathering, they stay in the pupae for about 7 days, and then bite the feathered hole to climb out of the hole, and from late May to June is the peak of adult tree emergence, and june to July is the egg laying period of adult insects. After the adult worms emerge from the hole, they need to eat young shoots as supplementary nutrition, which will spread the pine wood nematodes carried on the body to the healthy trees that are eaten. Pine brown tianniu likes to lay eggs on weak wood, before spawning female insects bite a moment on the trunk of the slot to lay eggs in the groove, eggs can be seen from early June to September, each female can lay 100 to 200 eggs, adult lifespan of 34 to 100 days. After hatching, the larvae first feed on the tender tissue under the bark, and after 3 years of age, they moth into the xylem. Pine brown tianniu prefers well-lit and high-temperature environments, so sparse forest stands, forest edges, and forest clearings occur more often. The adult spread distance is about 1 to 2.4 km.
4 Prevention and control methods
4.1 Strict quarantine
Carry out quarantine inspections, strengthen the supervision of wood-related units and individuals, prevent the transmission of pine wood nematode disease in the transportation of insectated timber, and severely crack down on the illegal transfer, operation and processing of pine wood without quarantine.
4.2 Forest prevention and control
Suitable place for trees, create mixed forests, strengthen care management, strengthen mountain closure and afforestation, and timely clean up insect sources.
4.3 Chemical control
Scattered pine forests can be controlled by aircraft spraying, and scattered pine trees can be controlled by ground spraying. After the control area is determined according to the control needs, at the beginning of the feathering of vector insects and the end of the effective period of the first spray, the high-efficiency, low-toxicity, environmentally friendly sustained-release agents are selected for two consecutive applications.
Perforation injection control is applicable to ancient and famous trees and pine trees that need key protection in parks, scenic spots, temples and other areas.
4,4 Prevention and control of natural enemies
In the larval stage, worm holes can be injected with a suspension of albicans plus a synergist. The ratio of releasing Tubal Swollen-legged Bees, Swollen-legged Bees and Celestial Bull Larvae is about 5:1. The ratio of the release of adult flower velvet beetles or eggs is about 0.5:1 between the release of adult flower and the invasion hole of tianniu, and the ratio of the release of flower velvet parasite eggs to the number of tianniu is about 9:1.
4.5 Booby trap control
Trap booby trap: Set up traps 1 to 5 days before the feathering of pine brown cattle, generally set up every 1 hectare, and try to set up in the relatively open and well-ventilated areas of the forest. The trap is suspended vertically, the lower end is about 1.5 meters from the ground, the core should be replaced in time, and the trapped adult pine brown cattle should be collected and processed regularly.
Vertical Lure: 2 months before the local vector insect feathering, select weak pine trees as lures, and set 1 plant per 0.7 hectares. The lure wood is crushed (sliced) or burned during the non-feathering period of the pine brown cattle in winter and spring.