What do you know about the Northeast Great Blackgill Golden Beetle?

Adults are 16-22 mm long, black or black-brown, shiny. The elytra are oblong and have 4 distinct longitudinal ribs on each side. The protocavity segment has 3 teeth on the lateral side, 1 distance on the medial side, and a complete spiny transverse ridge in the middle of the posterior cavity segment.

The eggs are oval in length, millimeters long, white with a yellowish-green sheen, spherical in the later stage, and yellowish-white when nearly hatched. The larvae are 35-45 mm long, with a yellowish-brown head and a milky white abdomen. The anterior and parietal bristles of the head are 3 on each side in a longitudinal row.

The hole of the rainbow door is in the form of a three-shot slit, and there are no prickly hairs in the compound area behind the visceral abdominal piece, and the hook-like bristles are scattered. Pupae naked pupa, 21-23 mm long, white at first, then yellowish-brown to reddish-brown after 7 days. There is 1 pair of forked protrusions at the end of the abdomen.

The name of the insect is Coleoptera, gill beetle. In China, it is distributed from Heilongjiang, Inner Mongolia and Xinjiang in the north, Jiangsu, Anhui, Hubei and Sichuan in the south, from the east of the former Soviet Union in the east, to Gansu in the west, and into Sichuan. It is found in apples, pears, peaches, plums, apricots, plums, cherries, walnuts, and a variety of crops.

The larvae eat all kinds of vegetable seedling roots, and the adults only eat the leaves and some crop leaves, and the larvae can make the vegetable seedlings die, resulting in the lack of seedlings and broken ridges. The darkgill beetle is a pest of the Coleoptera family Beetle. Adults are 17-22 long, 9 wide, narrowly and elongately ovate, covered with black or black-brown hairs, dull.

The dorsal plate of the anterior thorax is widest after the middle of the lateral margin. The small shield is a wide arc-shaped triangle. Elytra elongated, margins almost parallel to each other, slightly enlarged posteriorly, 4 ribs on each side inconspicuous.

The tibial joints of the forefoot have 3 external teeth, and the middle teeth are distinctly close to the top teeth. The ventral plate of the abdomen has a bluish-cyan velvety color. The oval is oval, milky white, and the body of the insect can be seen through before drunkenness.

The mature larvae are 35-45 long, the head is broad, and the anterior parietal hairs of the head are located at the crown gap two times. The body length is 20 -25 and the width is 10 -12. 2 pairs of articulators on the abdomen.

The caudal segment is triangular, and the two tail angles are obtuse and bifurcated. The larvae of the darkgill beetle mainly feed on the underground part of the plant, often eating the fibrous roots, nodules, and tenant roots of the plant, and eating the epidermis of the taproot. Adults mainly feed on leaves and have the characteristics of gluttony.

There is 1 pair of forked protrusions at the end of the abdomen. In soybean fields and some peanut fields, the larvae developed rapidly, and most of the larvae moved down to overwinter in September. The larvae in the grain fields develop slowly, and they can continue to damage wheat in September. It is distributed in Northeast China and North China.

Grubs are important underground pests, due to different climates and soils, in different grassland and lawn types, there are certain differences in the types of damage, and generally a variety of mixed occurrences occur in the same area. According to the living habits, you can judge what is the Northeast great blackgill beetle. Habits and morphological characteristics are important bases for judgment.

(Li Kuansheng).

Scientific name: Holotrichia diomphalia (BATES). Coleoptera, gill beetle.

Adult body 15 17 mm long, oblong-oval, shiny surface; head, prothorax dorsal plate, and elytra densely dotted; There are 4 longitudinal lines on the elytra, the conjunct line is wide and raised; The hip plate is raised, slightly concave in the middle, dividing the bulge into two dwarf round-convex. The antennae of the male are lamellar and long beyond the sum of the last 6 segments, the outer margin of the tibia of the forefoot has 3 teeth, and the triangular pit in the middle of the fifth ventral plate is wider. The larvae have a head width of millimeters, a body length of 31 millimeters, 3 anterior parietal hairs on each side of the head, in a longitudinal row, and only scattered hook-like hairs on the ventral surface of the buttocks.

It is distributed in Heilongjiang, Jilin, Liaoning, Inner Mongolia, Hebei, Henan, Shaanxi, Gansu, Hubei, Jiangxi, Fujian, China; Japan, North Korea, Mongolia, Soviet Union. It is harmful to black locust, poplar, willow, elm, maple poplar, neem, metasequoia, camellia, black tree, chestnut, walnut, pine, Korean pine, pine sylvestris, larch and crops. 1 generation in two years, with adults and 2 to 3 instar larvae overwintering in the soil.

In May and June of the following year, at 8 to 10 o'clock on a warm night, the overwintering adults are unearthed. Male adults are phototaxis. Prevention and control methods:

Artificial killing of adult insects; Seed dressing with phosphine; During the growth of seedlings, the rhizosphere was perfused with phosphine or 25% isopropylphos, 90% trichlorfon 100 times liquid poisoning to kill larvae.

Adult beetle of the Northeast large blackgill beetle.

The large blackgill beetle feeds on the rhizomes by larval bites. In Cixi, the first generation occurred in Cixi, and the overwintering larvae of the third instar larvae and a very small number of newly emerging adults occurred from late June to late November, mainly concentrated in August and October.

Use 25% chrysanthemum ester and 1000 times water to water the root control.

The large blackgill beetle in Northeast China has 1 generation in 2 years, and in Central China, Jiangsu and Zhejiang and other places in 1 year l generation, it overwinters as adults or larvae. The overwintering adults emerge from the soil activity around mid-April until they sting in September, which lasts for 5 months, lays eggs from late May to mid-August, and hatches one after another in mid-June, harming the 2nd or 3rd instar to overwinter in December; The overwintering larvae continue to develop in April of the following year, pupate in early June, enter the peak stage in late June, and lurk in the soil after becoming adults in July, and overwinter successively until the spring of the third year. The life history of the Tohoku region has been postponed by more than half a month.

Adults are latent in the soil during the day, active at dusk, and the peak of excavation is 8-9 o'clock, with suspended animation and phototaxis; After excavation, you like to gather on the side of the road and the ground where the bushes or weeds are overgrown, and lay eggs in the nearby soil, so the seedlings on the edge of the ground are more seriously damaged; Adults have the habit of mating and laying eggs one after another, laying eggs up to 8 times, and the female dies about 27 days after laying eggs. Doki spawns in moist soil at depths of 6-375px, with an average of 32-193 eggs per female, with an average of 102 eggs, and an egg period of 19-22 days. The larvae of the 3rd instar have the habit of killing each other, and often move forward along the ridge direction and seedling rows, and the larvae are easy to find under the fresh infested plants. The larvae move up and down with the rise and fall of ground temperature, the larvae move upward from the depth of the soil when the ground temperature reaches about 10 at 250px in spring, and mainly feed at 5-250px when the ground temperature is about 20, and migrate to the depth when the ground temperature drops below 10 in autumn, overwintering at 30-1000px.

Soil that is too wet or too dry will cause a large number of larvae to die (especially larvae below 375px), and the suitable soil moisture content for larvae is that the first instar larvae will die quickly when it is less than 10%; Irrigation and rainfall also have an impact on the distribution of larvae in the soil, if rainfall or irrigation is suspended and moved to the depths of the soil, if flooded, a cavity is made in the soil, if soaked for more than 3 days, it is often suffocated to death, so irrigation can reduce the harm of larvae. The mature larvae pupate in a soil chamber at a depth of 500px, with a pre-pupal period of about one day and a pupal stage of 15-22 days.

Northeast blackgill beetle: June and August are rampant, larvae (grubs) feed on the lower disc roots and bulb discs, until the entire bulb is destroyed. Prevention and control methods:

Before fertilization, spray the manure with 500 800 times of 80% dichlorvos emulsion, mix well, and cover with plastic film to kill the larvae in the fertilizer. In the damage period, the soil is irrigated with 50% malathion 800 1000 times, or 25% phoxanthion and 25% methamidophos acetate 1000 times.