How to control the piercing and sucking pests of garden trees.

Needle-sucking pests are a major category of garden tree pests. Their harmful characteristics are sucking the sap of trees and plundering their nutrition, which generally does not affect the integrity of the external morphology of trees. However, the damaged tree organs often show fading, yellowing, curling, deformity, malnutrition, wilting, early defoliation, and even the whole plant withers and dies in severe cases. This kind of pests not only do harm directly, but also bring endless troubles to trees, such as holes caused by pricking and sucking, juice outflow, etc., which become invasion channels of pathogenic microorganisms and induce tree diseases (such as sooty blotch). In addition, this pest is also an important disseminator of tree virus diseases. According to records, Myzus persicae can spread at least 107 virus diseases.

Sucking pests have strong reproductive ability. Aphids and some scale insects can parthenogenesis and easily spread to other places with their hosts. Therefore, it is particularly important to quarantine it in the process of prevention and control.

(1) aphid

Aphids, also known as borers and nectar insects, are one of the most common pests of garden trees. Aphids are small, soft and have long antennae, generally 6 nodes. Most aphids have a pair of "abdominal tubes" on the back of their abdomen. Aphids have winged individuals and wingless individuals; Different body colors, such as green, yellow, orange or black. Aphids are extremely fertile, including parthenogenesis and bisexual reproduction, viviparous reproduction and viviparous reproduction. They can breed for several to dozens generations a year, and can breed for 4-5 days in summer 1 generation. Aphids use needle-like mouthparts to absorb nutrients from plants, and gather on leaves, tender stems, flower buds, terminal buds and new shoots by hundreds, causing abnormal growth of plants, shrinking, curling and even falling off leaves, and even causing trees to wither and die in serious cases. The honeydew secreted by aphids affects the photosynthesis of plants and easily induces sooty blotch. In addition, it can spread some viral diseases.

1. Common aphid species

(1) Myzus persicae

Also known as Myzus persicae and Myzus persicae. Harm peach, plum, cherry, begonia, Buxus macrophylla, hibiscus, plum flower, oleander, rose and other garden plants.

(2) Cotton aphid

Also known as greasy worms, oily worms and honey worms. It mainly harms Buxus macrophylla, Hibiscus, Hibiscus, Platanus, Pomegranate, Bauhinia, Rose and so on.

(3) Apple aphid

Also known as Apple Yellow Aphid and Spiraea Aphid. Widely distributed, it harms apples, pears, peaches, cherries, hawthorn, citrus, loquat, begonia and other trees.

(4) Aphids in China

Also known as rose aphid. Distributed in East China, Central China and South China. It mainly harms roses, roses, roses, ten sisters, Prynne and so on.

(5) China locusts.

Also known as oil bugs and greasy bugs. Distributed in North China, Northeast China and other places, it mainly harms the buds and leaves of plants such as Robinia pseudoacacia, Sophora japonica and Amorpha fruticosa.

2. Aphid control methods

(1) Remove fallen leaves and weeds near trees, and reduce the overwintering population density.

(2) Spraying 3 ~ 5 Baume lime-sulfur mixture on trees during dormancy, which should be even and thoughtful, especially on the cracks between buds and bark, in order to kill overwintering eggs.

(3) Pay attention to the protection of natural enemies of aphids such as ladybugs, lacewings and syrphids.

(4) The following chemical pesticides can be selected in the aphid occurrence period: spraying 10% wettable powder for killing aphids 4000 times, 3% mirex 2000-3000 times, 48% Lethbone 2000 times, 4.5% beta-cypermethrin 2000 times, and 50% baichongdan wettable powder 65438.

Thank you (2) Scale insects Scale insects are small insects, most of which are covered with waxy secretions. The female insect has no wings, while the male insect has a pair of membranous front wings, and the rear wing degenerates into a balance bar. Scale insects are common pests in garden trees, and often gather on branches, leaves and fruits. Adults and nymphs insert needle-like mouthparts into the leaves and branches of trees to absorb juice, which makes the branches wither and even the whole plant die, and can induce sooty blotch.

Scale insects have strong reproductive ability and occur for many generations a year. Eggs hatch into nymphs, and after a short period of crawling, they form shells and are fixed on branches and leaves to suck. Scale insects have strong drug resistance, so it is difficult for general drugs to enter the body, and it is difficult to control them. So once it happens, it is not easy to eliminate it.

1. Common species of scale insects

(1) scallop

Also known as white cockroaches, cotton balls and so on. Eating habits are very diverse, and harmful ones are rose, rose, rose, boxwood, osmanthus, camellia, magnolia, camellia, smiling, pittosporum, hibiscus, kumquat, pomegranate, peony, Milan, lemon, fig and so on.

(2) Ceroplastes japonicus

Also known as Japanese wax scale and jujube wax scale. It is distributed all over the country, and its eating habits are very diverse, which harms all kinds of ornamental trees, such as Chimonanthus praecox, pomegranate, gardenia, magnolia, smiling face, peony, ivy, oleander, peach, begonia, crape myrtle, hawthorn, boxwood, apple, pear and jujube.

(3) mealybug corning

Also known as pear mealybug and mulberry mealybug. It is widely distributed and mainly harms pears, pomegranates, peaches, plum blossoms, grapes, begonia, oleander, citrus, gardenia and ivy.

4) Mulberry bark

Also known as mulberry shield scale, mulberry Bai Dun scale, etc. Distributed all over the country. Harm peach, plum blossom, clove, hibiscus, palm, cycad, camellia, hibiscus, red fruit, grape, etc.

(5) Coccidiosis in North Korea

Widely distributed, harmful to plum blossom, peach, begonia, peach, apricot and so on.

(6) Pear scales

It mainly harms Rosa roxburghii, Rose, Pearl Plum, Begonia, Plum Blossom and Grape.

(7) Sugar-coated scale

It mainly harms roses, coconuts, figs, camellias, crape myrtle, plum blossoms, grapes, hibiscus, Euonymus japonicus and so on.

2. Prevention and control methods

(1) Strengthen quarantine

The scale insects have little activity, limited self-spreading ability and concentrated distribution. Therefore, in the process of exchange and transportation of garden trees, quarantine should be strengthened to prevent artificial diffusion.

(2) Manual control

In the process of tree maintenance, if pests are found in individual branches and leaves, the branches and leaves will be cut off or scraped off immediately and burned centrally.

(3) Protect and introduce natural enemy insects

Such as Australian ladybug, scarlet ladybug, black-edged ladybug, etc., have a good control effect on scale insects; Ladybugs not only feed on adults and nymphs of mealybug, but also on oocysts. The LEPIDOPTERA geometrid is the most important parasitic wasp of the red wax scale. Wasps, wasps and ladybugs are all natural enemies of scale insects, which can be used to control the harm of scale insects.

(4) chemical control.

(1) control during dormancy: spray 3 ~ 5 pomeranite mixture or 3% ~ 5% diesel emulsifier on trees during dormancy, or apply 65,438+0.5 ~ 20 times of jiaodi EC to control overwintering scale insects.

② Control in growth period: The scale insects do not occur in short incubation period or initial incubation period, which is the key period of chemical control. The following chemicals can be selected: 0. 1 ~ 0.5 Baume sulfur mixture, 80% dichlorvos 1500 ~ 2000 times, 50% marathon EC 1000 times. Spraying should be even and thoughtful, spraying once every 7 ~ 10 day and spraying continuously for 2 ~ 3 times can control the harm of scale insects.

(3) Starscream

Also known as fire dragon worm, it is an important leaf pest. Red spider is very small, round or oval, orange or reddish brown, with strong reproductive ability, which can reach 10 ~ 20 generations a year, and can reproduce sexually or parthenously. Red spider mainly sucks the juice from leaves with nymphs and adults, and the chlorophyll in the damaged leaves is destroyed. When the damage is serious, the leaves show dense and fine gray-yellow spots or patches, and the leaves gradually wither and fall off, even become polished, which seriously affects the growth of garden trees.

1. Common types

(1) hawthorn spider

Also known as hawthorn spider mite. It is distributed all over the country and mainly harms hawthorn, begonia, begonia, dark plum, apple, peach, apricot, plum, cherry, cherry blossom, locust, pomegranate and hibiscus. And harm adults and nymphs by sucking juice.

(2) Panonychus apple

Also known as Red Spider of Apple, Red Spider of Elm and Red Spider of Europe. (figure 1). Widely distributed, it mainly harms apples, pears, peaches, oranges, grapes, Chinese rose, begonia, Prunus microphylla, cherry blossoms, roses and wild roses.

Figure 1 Panonychus apple

(3) Tetranychus cinnabarinus

This is a worldwide pest mite. It mainly harms garden trees such as rose, hibiscus, magnolia, hibiscus, begonia, plum blossom, Chimonanthus praecox, cherry blossom, jasmine, crape myrtle, osmanthus and peach.

(4) Tetranychus urticae

It is distributed all over the country, especially in the north. It mainly harms garden trees such as rose, wild rose, jasmine, osmanthus, wolfberry, Broussonetia papyrifera, apple, pear, peach and cherry, and has spread rapidly in recent years.

2. Prevention and control methods

(1) Protect natural enemies, such as mite-eating ladybugs, midges, thrips, black lacewings, lacewings, mealybugs, predatory mites, etc. Use less broad-spectrum pesticides and acaricides.

(2) Before the overwintering adult mites emerge from the sting, that is, before and after the sting, carefully scrape off the coarse, old, sick and warped skins on the branches of garden trees, clean up the weeds and fallen leaves under the tree tray, and concentrate them in the leeward and sunny places nearby, and burn them after the weather gets warmer and the natural enemies such as ladybugs and midges move out.

(3) Before the garden trees germinate, spray 3 ~ 5 Baume lime-sulfur mixture on all parts of the trees by washing to kill all kinds of harmful mites. However, it is effective to spray 95% oil emulsion 100 times in the year when panonychus citri lays a lot of eggs.

(4) When the red spider occurs seriously in the growing season, the following chemicals can be selected in time: 15% pyridaben EC 1500 ~ 2000 times, 40% dicofol 700 ~ 800 times, 5% nisolone 2000 times, 1.8% azithromycin. 20% amitraz 1000 times solution and 5% acetamiprid-2,000 times solution with remarkable efficacy at high temperature can be selected when serious mites occur in July and August. In addition, when Tetranychus urticae harms seriously, 0.3% dipyridamole EC 2500 times solution and 1% chlorfenapyr 2000 times solution can be selected.

(4) whitefly

Also known as white moth and greenhouse whitefly (Figure 2). It is the main pest of greenhouse flowers and trees, which harms jasmine, orchid, rose, peony, hibiscus and other greenhouse flowers. Adults and nymphs suck mesophyll juice, which makes the leaves fade, turn yellow, wither and even dry up. In addition, a large number of secretions will lead to sooty blotch, which will seriously affect the ornamental value and spread viral diseases. Under the natural conditions in the south, whiteflies can harm all the year round, while in the north, they can only harm in greenhouses all the year round. There are more than ten generations in a year, and the generations overlap seriously. Adults have a strong tendency to be yellow.

Fig. 2 whitefly

Prevention and control methods:

(1) Using the strong yellow preference of whitefly, yellow wooden boards or plastic boards coated with sticky oil can be hung or inserted beside plants, and the branches of flowers and trees can be vibrated, so that the adults of whitefly can fly and tend to stick to the yellow boards, thus playing a role in trapping and killing.

(2) Using natural enemy Taiwan Province aphid to control Taiwan Province aphid has been commercialized abroad. When used, the benefit ratio is 1: 30 ~ 40, which can effectively control whitefly.

(3) chemical control. Spray 80% dichlorvos EC 1000 times, 25% chlorpyrifos WP 2000 times and 40% omethoate 1000 times. The generation overlap of this insect is serious, and it needs to be sprayed 1 time every 6 ~ 7 days, and sprayed continuously for 2 ~ 3 times.

(5) Pear Net stinkbug

Also known as the army with worms (Figure 3). Distributed in Central China, North China and East China. It mainly harms pears, apples, shaguo, begonia, hawthorn, peach, plum, quince, camellia, rhododendron, begonia, rose, smile, peach, wintersweet, plum and jasmine. In backstab, adults and nymphs cluster and suck juice, and yellowish spots appear in the corresponding parts of the front of leaves, which are light and concentrated near the veins, and the whole leaves turn yellow and white, leading to early defoliation. Black sticky substances of different sizes appear on the back of leaves.

Figure 3 Pear Net stinkbug

There are 3 ~ 4 generations a year in North China, and adults overwinter in weeds, fallen leaves, bark cracks, old stubble skin and clods. Adults move slowly and in droves.

Prevention and control methods:

(1) Remove fallen leaves and weeds in winter and spring, scrape bark and eliminate overwintering adults.

(2) After the overwintering adults emerge, 50% acetaminophen 1 000 times solution, 40% omethoate 800 times solution and 20% Juma EC 1500 ~ 2000 times solution can be sprayed at the stage of1generation nymph. Continuous spraying for 2 ~ 3 times can achieve good control effect.