Drill moth pests on lychees are very difficult to control, resulting in a decline in the yield and quality of lychees, which seriously affects the economic interests of fruit farmers, such as many borer pests can lead to young fruit shedding, insect fruits, etc., and dried moth pests can harm lychee trunks and young shoots.
So what are the main types of borer pests in China's lychee producing areas? Together, we followed the professional article published in "South China Fruit Tree" by Chen Bingxu, an expert in the pest prevention and control position of the national lychee longan industrial technology system, and achieved targeted prevention and control in the future!
First, the main drill moth pests
1. Lychee moth
Pest status: mainly harmful to lychee fruits and flower spikes;
Life rules: Lychee flower spike stage began to feather, at the end of March and early April in Guangdong region appeared adults; larvae after ripening from the fruit, the worm hole is flat and round. Generally, the pupae form thin cocoons on the leaf surface near the ear of fruit, and a few pupate on the deciduous leaves on the ground. The larvae in the fallen fruit pupate on weeds or leaves on the ground. The pupal stage is 6-12 days, 7-8 days at 26 °C. After feathering, adults lie still under the branches in the canopy during the day, their body color is closer to the bark, and they fly briefly when disturbed, but soon they inhabit nearby branches or other plants, and their flight ability is not strong.
2. Lychee tip moth
Harmful status: harmful to young leaves and branches;
Life rules: larvae overwinter in the winter shoots, leaf veins, flower spikes, from late March to mid-April of the following year, crawl out of the wintering place and cocoon pupae on the nearby leaves, begin to feather and lay eggs in early to mid-April, eggs are scattered on both sides of the midrib of the young leaf surface of the new shoots; the hatching larvae feed on the host epidermis from the bottom of the egg shell to take the juice, and from the 3rd instar to the moth host tissue (including the young leaves, petioles, and tender stem marrow). The middle vein of the young leaf is damaged by several fecal holes on the outside, which are brown and curly and dry at the ends of the leaves; if there is not enough food, the larvae can turn to the midrib or shoot of another leaf. The first moth into the new shoot is harmful, the appearance of no obvious symptoms, but the marrow becomes black, there is black brown powdery insect feces inside, as the larvae grow, the top of the branches appears to shrink, the leaves are easy to fall off. The larvae generally drill moths into the young part of the tip, and each tip usually has 1 larvae, and many have 3-4 heads. The larvae crawl out of the moth tunnel after ripening and form a thin cocoon on the back of the leaves in the lower canopy.
3. Tianniu
Pest status: Turtle-backed tianniu is the main borer pest that harms the trunk of lychee trees, and adult insects can be seen in the field from early June to late November, with the most in July and September;
Life rules: After the adult insects feather, they first feed on the young shoot cortex of lychee, longan, grape, etc., and the young shoots die. Eggs are mostly laid under the cortex of branches or branches, and are scattered individually. The egg stage is about 10 days. The hatching larvae feed under the bark of the tree and then gradually moth into the xylem of the branches, forming a flat, longitudinal moth. The larvae moth from top to bottom. The mature larvae cover both ends of the cocoon chamber with secretions and feces in a spacious part of the moth passage.
4. Roll moths
Pest status: There are a total of 5 species of moths that are harmful to lychee fruits, of which brown-banded long-leaf moths are more common in different provinces (regions), but generally moths are less harmful;
Life rules: Brown-banded leaf-curly moth overwinters in lychee, longan and other curly leaves as larvae. Overwintering larvae precipitate in early spring after feeding on flower spikes or leaves for a period of time, and then feather; the first generation of larvae are mainly harmful to lychee larval fruits. Second-generation larvae turn to longan larvae because the lychee fruit is ripe. The third generation of larvae occurs when the longan fruit is also nearly ripe, and it turns to the leaves and young shoots. Adults are mostly feathered in the early morning, lying still on the branches and leaves during the day, nocturnal, and slightly phototropic. Spawning is laid 3-4 hours after mating, and some are extended to the next night. The eggs are laid near the main veins of the leaf surface or in the slightly concave part of the leaf surface. The eggs are oval in shape and arranged in the shape of fish scales. Overwintering larvae mostly pupate in tangled bouquets of fallen flowers on the tree, and some pupate among the old leaves. During the fruit infestation period, some of the larvae pupate in the fallen fruit. Others pupate between the old leaves, pupal period 5-9 days.
5. Silverfish
Pest status: There are three main species of beetles that harm lychee (flint-edged cunning long beetle, dichophyllum long beetle and tea-based small beetle), which are often mixed and infested;
Life rules: Tea beetles mainly overwinter in the original moth tunnel with adult insects, and some overwinter with larvae and pupae. After the temperature rises in mid-to-late February of the following year, the overwintering adults go out to move out and drill moths to form new moth channels. Spawning begins in early April. After each generation of adult insects feather, they inhabit the original tunnel for about 7 days before drilling out of the moth path, especially in the sunny afternoon. After the hole, the adult insects mostly moth in the leaf marks and branches of the 1-2 years old branches, forming moths. The borer hole is round, about 2 mm in diameter, and there is often wood chips accumulating at the orifice. The moth path can reach as deep as xylem and is a ring-deficient horizontal tunnel. The eggs are laid in the tunnel, the egg calendar period is about 6 days, the larvae live in the mother tunnel, the old mature larvae pupate in the original tunnel, and the pupal period is 4-5 days. Wintering usually begins in mid-to-late November.
2. Comprehensive prevention and control
1. Agricultural prevention and control
Strengthen water and fertilizer management, timely prune diseased and weak insect branches, timely scrape off insect eggs at the base of the trunk or find insect eggs, and concentrate on destruction; avoid planting mulberry trees, trees such as trees that are easy to attract tianniu near orchards.
2. Physical prevention and control
The park is equipped with black lights to trap and kill phototropic pests; paint the trunk white to reduce the spawning volume of tianniu; and assassinate larvae.
3. Chemical control
(1) Borer pest (number one pest: lychee moth)
Strengthen forecasting and grasp the critical period of prevention and control;
"Before, during and after control, adults, hatching larvae and eggs are killed together";
Use of agents or formulations capable of killing both adults, larvae and eggs;
Such as high-efficiency cypermethrin, high-efficiency cypermethrin, bifenthrin and other organophosphorus, avermectin and methylamino avermectin benzoate, insecticide, urea and other pesticides.
(2) Dried moth pests
Adult blooming period: spray high-efficiency cypermethrin, cypermethrin, bifenthrin, etc.;
Larvae drilled into the xylem: Cotton balls dipped in 80% dichlorvos emulsion 10 times liquid at the mouth of the hole, sealed with yellow mud, fumigated to kill the larvae.
4. Biological control
Prevention and treatment of Tianniu: flower velvet beetle, Guan's swollen leg bee, long-tailed wasp, Tianniu egg wasp, etc.;
Control of moth pests: red-eyed wasps;
Biopesticides: Bacillus thuringiensis (Bt), green/white zombies, plant-derived pesticides such as neem, etc.
Article source: There are lychees
【Disclaimer】Reproduced from other platforms or media articles, the platform will indicate the source and author, but the platform does not provide any express or implied guarantee for the accuracy, reliability or completeness of the content contained, for the reader's reference only. If you infringe copyright, please take the initiative to contact the platform and provide relevant written evidence, the platform will correct the source and author or delete the article within 24 hours according to the opinions of the copyright owner, and do not assume any other responsibility.
And much more
Pay attention to the "Hainan Agricultural Technology" WeChat public account
Soil testing formula fertilization | Diagnosis of animal and plant blight
Expert online consultation | Share agricultural knowledge
Publish agricultural policy | Publish agricultural prices