Brown gill golden turtle, belonging to the coleoptera, golden turtle family, adult insects in jiaodong area is called ground yellow, yellow bright, blind bump, etc., after catching can be fried or grilled after eating, is a kind of cuisine in parts of Jiaodong.
The brown gill golden turtle is regarded as a local delicacy in Weihai
Brown gill golden turtle is one of the important underground pests in unformed forests and newly planted forests, mainly harming seedlings and young trees such as sassafras pine and larch, the victimization rate can reach 50%, and the larvae eat germinated seeds in the soil to cause lack of seedlings; bite off the root neck and root system of seedlings, so that the plants die, and the wound is easily invaded by pathogens to cause disease. In the eastern part of the gum divided into age orchards, it was found that the brown gill golden turtle larvae can harm apples, cherries, pears and other fruit trees for many years, and eat the root system of fruit trees, resulting in weak trees and even dead trees.
Elderly orchards with high soil organic matter content occur more frequently. Once the brown gill golden turtle occurs in large numbers, it will have a serious impact on the fruit industry. Since 2012, the author has systematically observed the occurrence of brown gill golden turtles in Weihai area, and explored effective control methods.
1 Morphological characteristics
Adult: The body color is tan, the body length is 2.5 to 3 cm, the width is about 1.5 cm, the dorsal plate of the forebrea is equal to the base of the elytra, the small shield is triangular, smooth, and the thorax has villi. The two elytra have 4 longitudinal ribs each. The adult insects planed under the peach and plum trees are thinner and smaller than the adults planed under the large cherry and apple trees, and the adults planed under the persimmon trees are darker.
Eggs: Initially milky white, oval, 0.3 to 0.4 cm long and 0.2 to 0.25 cm wide. After gradually becoming larger, the length can reach about 0.6 cm and the width before hatching, and the larval peristalsis can be seen in the egg shell.
Brown gill golden turtle chest and abdomen
Larvae: "C" shaped. The body is milky white, the insect age is different, and the body length varies. Mature larvae are 4.5 to 5.5 cm long, with 1 to 2 bristles on each side of the anterior parietal of the head, and most of them are only 1. In the center of the hook-shaped bristle group on the web there are two parallel hair columns, each with 18 to 22 hairs.
Pupae: 2.0 to 2.5 cm long, initially white, then gradually turn yellowish, feathered anterior skull, foot, elytra become brown and gradually deepen. The pupal chamber is ovoid, 3.0 to 3.5 cm long and about 2.0 cm wide.
2 Hazard symptoms
Larvae mainly harm the root system of fruit trees such as apples and large cherries. Mostly occur in old orchards with older tree age, larvae gnaw at the roots of fruit trees in the ground 5 to 10 cm below the surface, the epidermis of the main root part is gnawed off, showing mottled, xylem is exposed, affecting the water of the tree, inorganic nutrient absorption, making the tree weak, the germination time is delayed, affecting flowering and fruit setting, causing yield reduction, and causing tree death in severe cases.
3 Occurrence and life habits
After observation, the brown gill golden turtle completes 1 generation every 2 years in the Jiaodong area, overwintering as adults and larvae. In general, the number of adult insects in singular years is relatively large, and the occurrence in even-numbered years is relatively light, similar to the size of apple growth.
Brown gill golden turtles overwinter as adults and larvae
Overwintering adults occur for a long time, with a calendar period of more than 80 days. Since March of each year, as the temperature rises, the overwintering adults gradually ascend from 10 to 50 cm underground to the soil layer of 5 to 10 cm, and in late March, adult worms can be seen 1 to 5 cm deep in the soil layer under the tree. Adult insects in jiaodong generally begin to be excavated sporadically in mid-to-late March, and gradually enter the peak excavation period before and after the budding of apples in late March and early April, and the excavation time is earlier than that of apple-haired scarab beetles. On March 30, 2017 and March 27, 2019, birds such as magpies were observed preying on orchards to unearthed adult insects.
Adults dug out about 5 cm underground
After rain or watering in early to mid-April, the soil layer of 5 to 10 cm is moistened, and the adult insects are concentrated, and a large number of excavation holes can be seen on the ground after excavation. Adults begin to mate as soon as they emerge. On the evening of April 5, 2020, a large number of adult insects crawled on the ground, paired and entered the cave to mate in the old orchard of Kongjiazhuang in Rushan, Weihai. April is the peak period for excavation, around April 10 is the peak period of adult activity, late May is the end of the period, and individual adults can still be dug up in the soil. Very few adult worms have been unearthed from late May to early June. The excavation calendar lasted about 60 days.
Observed from the excavation time point, adult insects are rarely seen before 6 pm in the orchard, one reason is that there are few excavations, and the other reason is that the excavated adult insects are easily preyed upon by birds. After 6 o'clock, the sun sets, magpies and other birds nest, and the number of brown gill turtles begins to increase. People usually catch brown gill turtles from about 6 o'clock until dark at about 7:30. After the excavation of the male insect low-altitude flight, a flight distance of about tens of meters, the female insect is not very active, only a short distance crawling or jumping flight, sunset 6-9 points is the peak period of brown gill golden turtle activity, pairing and into the cave mating, after pairing the general female in the front male behind, after entering the cave, the male insect with the foot quickly sealed the hole. As the temperature dropped, after 9:30 p.m., they basically entered the cave, and some of those who did not find a partner continued to seek mates, many of which were preyed on by toads, frogs, hedgehogs and so on. Many of the brown gill turtles that enter the burrows fall into the underground tunnels dug by the marmots and are preyed upon by the marmots. Adults generally do not feed, have weak phototropism, are insensitive to sweet and sour solutions, and have a diurnal and nocturnal habit. Observed in 2019, it may be affected by food sources, etc., the adult brown gill golden turtle dug out under the big cherry and apple trees is slightly smaller than the adult insects dug under the peach tree and plum tree, and the adult insects dug out under the persimmon tree are darker in color.
The eggs of the brown gill golden turtle are laid in mid-to-late April, and the eggs are mostly laid in the soil layer below 20 cm, and the eggs are laid at a depth of 20 to 30 cm soil layer, and the spawning period is about 10 days. A single female lays about 30 eggs.
Hatching larvae (also known as grubs) can be seen in mid-to-late May, larvae nibbling on roots such as fruit trees, and in late October the larvae dive into deep soil layers below 30 cm to overwinter. During March of the following year, the overwintering larvae rise to the tillage layer to harm the roots of fruit trees. The damage of the larvae to the fruit trees was relatively light in that year, and the food intake doubled in the second year, and the damage to the roots of the trees was aggravated. From mid-to-late March to November, larvae can be seen feeding on roots.
After the larva mature, dived to the deep soil layer to do the soil chamber pupae, in the Rushan White Beach Town Kongjiazhuang orchard observation found that in mid-October can see a large number of pupae feathers into adults and a large number of mature larvae pupae, in late November more than 99% of the old mature larvae into adult insects, the feathered adult insects did not emerge, lying in the soil chamber directly overwintering, until the following spring in late March began to emerge one after another.
Mature larvae pupate and pupae feathers into adults
4 Prevention and control methods
4.1
Biocontrol
4.1.1 Protect natural enemies such as marmots, frogs, toads, magpies and so on
Groundhogs, also known as mole rats, blind ground rats, blind arches, etc., are the main natural enemies of adult and larvae of brown gill golden turtles, preying on brown gill golden turtles that dig holes in the ground and stray into the ground rat holes. Groundhogs can not only eliminate underground pests such as brown gill turtles, but also loosen the soil. When there is a mud pile arched by the groundhog at the root of apples and large cherries, pay attention to protecting the groundhog.
4.1.2 Control using Bacillus insectii and insect pathogen nematodes
Dutky, S.R. et al. isolated and described Bacillus anchovy Japan, and further studied the method of inoculation and propagation of milky bacteria in live grubs, and the United States carried out control on more than 100,000 acres (1 acre = 6.07 acres) of land, effectively controlling the hazard of Japanese scarab beetles. Xie Simu and other studies found that the two milky bacteria (milky bacteria No. 1 and No. 2) screened in Shandong had strong pathogenicity for the dark gill golden turtle and the brown gill golden turtle. Li Suchun et al. used the heteronormal worm Taishan No. 1 to control two kinds of scarab beetles (large black gill golden turtle and dark gill golden turtle) with remarkable results.
4.1.3 Artificial predation of adults or planing of larvae
Adult brown gill tortoises have high nutritional value and are edible. Adult insects can be caught in the evening during the peak excavation period from late March to early to mid-April, reducing the amount of mating and spawning, and the best time to catch is 6:30 to 7:30 pm, that is, 1 to 2 hours after sunset. It is also possible to dig about 5 cm of soil from mid-March to early April to catch unexposed adult insects, or to manually plan larvae in the fruit tree tray during the budding period of fruit trees in the spring.
4.2
Plough the soil
The soil is ploughed before freezing, and the brown gill golden turtle after deep ploughing is exposed to the surface and preyed on by birds such as magpies, which can reduce the application of pesticides underground.
4.3
Pharmaceutical control
In orchards with relatively high soil organic matter content, brown gill golden turtle insect population density is often higher, mid-to-late March is the best time to control adult insects, can be combined with the sprinkling of soil fertilizer and other underground sprinkling octylthion granules, avermectin, cotton and other agents, and then covered with black recyclable mulch film, suffocated to death of adult insects to be unearthed, while playing a role in preserving moisture. During the excavation period, 4.5% high-efficiency cypermethrin can also be sprayed on the ground to kill adult insects. In the larval hazard period from March to October, octylthionate and avermectin can be used to irrigate the roots to kill the larvae. You can also use 25 kg of wood residue organic fertilizer per mu, spray the appropriate amount of water with octyl thion, avermectin and other agents into the wood slag and stir evenly, sprinkle it on the ground when the adults are unearthed, and finally carry out shallow planing and shallow picking. Modern orchards can control and control medicinal solutions such as avermectin through drip irrigation belts under the tree tray through fertilizer and water integration facilities.
4.4
Orchard grass
Orchard grass is conducive to the survival of brown gill, but because the larvae (grubs) eat grass roots, it reduces the feeding on the root system, which can reduce the harm to the root system of the fruit tree.
Author Friend of The Grower