Mesozoan is a kind of insect with a wide variety of species, which mainly survives by absorbing plant sap, which is very harmful to agricultural production. The following introduces the harmful symptoms and control methods of different types of mesozoans for your reference.
<h1>First, the harmful symptoms of different species of mesozoans</h1>
<h1>1. North Korean bulbous wax bug</h1>
This pest mainly harms plum, apricot, peach, cherry and other fruit trees, through the continuous absorption of sap to weaken the tree, severe when the branches die, plant death. It occurs in one generation a year, with two-year-old nymphs overwintering on the branches. In early to mid-March of the following year, it began to be active, crawling out of the peeling of the wax pile, finding another place to fix it, living in groups to feed on the branches, after the end of March, the back of the insect body became larger and spherical, the female began to incubate under the mother in early May, and the mid-May was the peak of nymph hatching, crawling on the host for 1 to 2 days, looking for a suitable place, with more leaf scars at the branch cracks and the base of the branches. After fixation, the body grows slightly, and a white filamentous waxy layer is secreted on both sides, covering the back of the insect body.
It is distributed in Northeast China, Hebei, Henan, Shandong, Shaanxi, Ningxia and other provinces and regions, and the hosts are plum, apricot, peach, cherry, etc., which occur commonly in mountain peach and apricot trees. Densely on the host branches, the host sap is sucked throughout the life, and the victim trees generally grow poorly, and the badly injured branches die, or even the whole plant dies.
North Korean bulbous wax bug
Critical periods for control: mid-March when wintering nymphs begin to shell and mid-May when nymphs hatch, when there is no covering on the back of the worm body, and the agent can play a better role.
<h1>2. Japanese wax</h1> bug
The pest mainly focuses on jujube trees, which in addition to affecting the potential of jujube trees by extracting sap, will also aggravate the incidence of coal pollution disease in plants because of the presence of secretions, which in turn will affect the photosynthesis of plants, and the yield and quality will decrease. A generation occurs once a year, with fertilized female adults densely overwintering on 1 to 2 years old sprigs, when the jujube tree germinates, it begins to feed as a pest, the insect body rapidly expands, in mid-June is the peak of the incubation period, incubation under the maternal shell, early July is the peak of the nymph shell, the shell nymph is fixed on the front of the jujube leaf and the young branches, and secretes wax to form a bug shell.
The domestic distribution is common, especially in the jujube producing areas of Hebei, Henan, Shanxi, Shaanxi, Shandong and other provinces. In addition to harming dates, it can also harm persimmons, pears, apples, chestnuts and so on. Nymphs and female adults gather on branches and leaves to suck up sap, and their secretions can still induce the occurrence of coal pollution disease, affect photosynthesis, and when severe, cause tree weakness, bud and leaf atrophy, yield and quality decline.
Japanese wax bug
Critical periods for control: before the female adults hatch, i.e. in late May and early July when the nymphs are in their prime.
<h1>3. Kang's mealybug</h1>
The pest mainly harms apples, pears, grapes and peaches and other fruit trees, its sap absorption site is more extensive, young shoots, young shoots, leaves, fruits and roots are its nutrient-absorbing parts, the early stage of the disease is often deformed, and the later stage begins to wither and die. Three generations a year overwinter with eggs in crevices in the trunks and thick-skinned branches of the dead trees. When the pear tree sprouts the following year, the overwintering eggs hatch into nymphs, which feed on the young parts of the host plant. In the first year, the nymphs are in mid-to-late May, the second generation is in mid-to-late July, and the third generation is in mid-August, and the female adults often crawl to the cracks in the thick skin of the branches or the calyxes and stems of the fruit to lay eggs, and some lay the eggs in the soil, and the eggs are laid in the egg sacs formed by the wax secreted by the female insects.
In addition to harming pears, it also harms apples, peaches, plums, apricots, cherry picks, grapes, hawthorns, persimmons, pomegranates, chestnuts, walnuts, plums, dates, mulberries, poplars, melons and vegetables. Adults and nymphs suck the sap of the host plant's young shoots, shoots, leaves, fruits, and roots. After the young branches are killed, they are often swollen, the bark is longitudinally cracked and withered, and the early fruit is deformed.
Kang's mealybug
Critical period of control: when the pear tree germinates during the incubation period of wintering eggs and the peak period of nymph occurrence in various generations, that is, mid-to-late May, mid-to-late July and late August.
<h1>4. Pear garden</h1> borer
This insect pest is similar to Kang's mealybug, mainly harmful to apples, pears, peaches, grapes and other fruit trees, but unlike Kang's mealybug, pear garden bugs mainly parasitize in the aboveground part of the plant, the key parts of the harm are mainly concentrated in the branches and fruit parts, the light branch growth is inhibited, the fruit is spotted, the heavy branches and leaves die, and the fruit loses its commercial value. Three generations occur in a year, with second-instar nymphs and a few fertilized females overwintering on the branches, feeding in mid-to-late March of the following year, fetal nymphs in early to mid-June, the second generation from late July to early September, and the third generation from September to early November.
Pear garden borer
The domestic distribution is general, and the harm area is biased to the north. Extremely heterogeneous, known host plants have more than 150 kinds, mainly harmful to fruit trees and trees, the main fruit trees are pears, apples, dates, walnuts, peaches, apricots, plums, plums, cherries, grapes, persimmons and hawthorns, etc., can parasitize all the aboveground parts of fruit trees, especially after the branches are killed, causing cortical wood thrombosis and phloem, catheter tissue decay, cortical bursting, inhibition of growth, causing leaf fall, and even branches drying and the whole plant death.
Key periods of control: the beginning of the wintering insect state is mid-to-late March and the wintering nymph period is early to mid-June.
<h1>5. Mulberry shield worm</h1>
Although this pest is harmful to apples, pears, peaches and other fruit trees, it is the most serious harm on peach trees. If such a disease occurs in peach trees, if it is allowed to reach more than 3 years, the entire orchard will lose its production value and can only be destroyed.
Mulberry shield worm
It is widely distributed in China, and occurs in the northeast, Hebei, Henan, Shandong, Shanxi, Shaanxi, Gansu, Inner Mongolia, Xinjiang and most provinces and regions in the south. The hosts are apples, pears, peaches, apricots, plums, plums, cherries, gooseberries, lotions, grapes, walnuts, persimmons, figs, mulberries, tea, cloves, palm trees, etc., of which the stone fruit trees are more seriously affected, especially the peach trees. Female adults and nymphs clumps are fed on fruit tree branches, occasionally harming the fruit and leaves. When severe occurrences occur, the shells are densely overlapped, and the surface of the branches is uneven, weakening the tree potential and even causing the death of the branches or the whole plant.
Critical period of control: The female begins to feed, that is, in mid-to-late March and at the end of each generation of egg hatching, that is, late May and early August.
<h1>6. Grasshoppers</h1>
The pest mainly harms apples, pears, peaches and other fruit trees, and the key parts of the harm are mainly concentrated in the young buds, some of the buds are withered, and the heavy ones are seriously weakened, and the yield drops sharply. Hosts include apples, pears, peaches, etc. Nymphs ascend trees in early spring and flock to young shoots to suck, causing the buds to wither, weaken the trees, and reduce yields. It occurs once a year, overwintering as eggs in the soil under the trees, under the weeds, etc. In February, the nymphs begin to hatch when the sap flows, crawling back and forth along the trunk at noon in the case of higher temperatures, and clustering in branches and holes at night.
It is found in Shaanxi, Xinjiang, Hebei, Henan, Shandong, Shanxi, Tibet and Yunnan. Host plants include apples, pears, apricots, peaches, plums, mulberries, chestnuts, walnuts, citrus, poplars, willows and so on. Nymphs ascend trees in early spring and flock to young shoots to suck, causing the buds to wither, weaken the trees, and reduce yields.
Critical period for control: The peak period for nymphs to reach trees is mid-March.
<h1>Second, the integrated control measures of different species of mesozoans</h1>
In fact, it is not very difficult to control the insect shell, as long as the fruit farmer grasps the occurrence law of the insect shell, finds the right method, and carries out scientific comprehensive control, the effect is good.
<h1> 1. Traditional method</h1>
The traditional approach is to control overwintering female adults by spraying whole trees with a stone sulfur compound before germination in early spring. However, many fruit farmers reacted that the prevention and control effect of this method was not very ideal, and the orchards that had been prevented and treated were still heavy in the later stage. The main reason is that the overwintering female adults have the protection of the shell, and the spring temperature is low, and the drug cannot penetrate into the shell, making it difficult for the overwintering female adult to kill.
Boiling stone sulfur compound
If the control of stone sulfur compound is used, it is recommended that the fruit farmer in mid-April to early May (there may be a difference in time between the north and the south, the fruit farmer can observe whether the adult worm lays eggs), take advantage of the female adult insect does not lay eggs, the old stem and large branches with a large density of the worm mouth are brushed off the insect body with a wire brush, and then apply the stone sulfur compound to kill the insect body remaining on the tree. In the process of application, we must pay attention not to spill the liquid medicine on the leaves, so that the leaves are harmed by the medicine. In addition, in the initial occurrence of spot orchards, the insect branches should be completely cut off, burned or artificially brushed with insect branches to eradicate the source of insects;
<h1>2. Artificial comprehensive prevention and control</h1>
Because the insect pest has no wings and no flight ability, it can only be transmitted over short distances by wind and rain, so it is necessary to strengthen the quarantine system in production and strictly prevent cross-border transmission of insect-bearing plant residues. In winter, orchards with severe occurrence of mesozoans are finely pruned, focusing on cutting the branches, leaves (evergreen fruit trees) and fruits attached to the eggs, and taking them out of the orchards for centralized burning or burial treatment.
<h1>3. Integrated biological control</h1>
The natural enemies of fruit tree shell insects are mainly predatory predators (red spot lip ladybird, black-edged red ladybird, etc.) and parasitic natural enemies (jumping wasps, short-margined hairy beetles, etc.), and biological control should be expanded in production through a combination of local protection and foreign introduction.
<h1>4. Comprehensive chemical control</h1>
When chemically controlling fruit tree mesozoans, two key periods should be seized, one is the reptile period of the first nymph or before the female adults lay eggs, and the other is the peak of egg hatching.
Tick agent
Pharmaceutical control: with the use of chemical control, in order to improve the insecticidal effect, it is recommended to add 0.1%-0.2% of the washing powder or silicone in the liquid, which can better penetrate the liquid into the waxy layer of the insect, which is that the liquid has a faster effect and kills faster. Available agents are 10% cypermethrin, 25% perchlorooctyl thionate, 48% chlorpyrifos, 50% chlorpyrifos emulsion, methotrex, mineral oil, matrine, ethyl spironoid + furazine, ethyl spiranterium + acetamiprid and other pesticides, it is recommended to spray again at intervals of 5-7 days, which can kill most of the adult insects of ticks. If you miss the peak period of egg laying of the insect shell, it is recommended to switch to the use of pine resin mixture (the preparation ratio is: 3 parts of raw rosin, 2 parts of caustic soda, 10 parts of water) diluted 10 to 15 times spray, spraying pine resin mixture has the effect of removing mold and disease, and can also play a good control effect.
<h1>Three views on the agricultural summary</h1>
The control of insect shell insects seizes 2 key periods, timely detection and timely medication, and will definitely be prevented.