The peak period for lepidoptera pest outbreaks is from June to August. Recently, a large number of Lepidoptera larvae have appeared in orchards to harm citrus peels and young leaves, which has seriously affected the growth of citrus. Some friends have been medicated many times, but they still can't beat these pests and can't do anything about it.
Lepidoptera is the second largest order of insects and is the most pest of insects in agriculture and forestry. Lepidoptera pests are also common in citrus, such as butterflies and moths, which are pests belonging to lepidoptera. Lepidoptera pests have always been very serious in agricultural production, and in citrus, it is a type of pest that is a headache, such as twill moths, smoke green insects, leafminer moths, butterflies, etc., which are all headaches.
< h1 class= "pgc-h-arrow-right" >, butterflies</h1>
Butterflies are a common lepidopteran minor pest in citrus, with the most common occurrences being citrus butterflies and jade-banded butterflies.
The young larvae (1 to 3 years) of the two species of butterflies are more similar, both are like a lump of bird droppings, the food is not large, and they tend to eat young leaves.
After reaching an advanced age (4 to 5 years old), the posture of the butterfly larvae has changed dramatically, and the amount of food has increased greatly, and the old leaves have begun to be nibbled, and the resistance to drugs has also increased.
Habits of life
● Pupae overwinter in 3 to 6 generations a year, feather into spring-type adults from March to April, and summer in July-August, and overlap generations in the fields.
● Adults alternate their tails during the day, and the eggs are laid on the back of young leaves or at the tip of the leaves; the larvae feed here after hatching, and can eat 5 to 6 leaves in their lifetime.
● When the larvae are startled, they stretch out their stinky horns to emit an unpleasant odor to avoid predators, and when they are old, they spit silk as a cushion head obliquely towards the suspended pupae.
<h1 class= "pgc-h-arrow-right" > second, nocturnal moths</h1>
It mainly includes twill moths, smoke worms, fruit-sucking moths and so on.
The twill nocturnal moth occurs throughout the country and is a bulivorous pest that is mainly harmful in gardens, where larvae bite leaves, buds, flowers and fruits. On the lawn, it is the key prevention and control object of Lepidoptera. The early larvae nibble on the epidermis and mesophyll of the leaf, leaving only the upper epidermis as a transparent spot; after 4 years, they enter binge eating, biting the leaf, leaving only the main vein. The Yangtze River Basin mostly occurs in July and August, and the Yellow River Basin occurs mostly in August and September.
The larvae have a dark brown head and a variable body color, generally dark brown, but also earth yellow, brownish green to black brown, the dorsal line is orange-yellow, and there are triangular black spots in the inner segments of the sub-dorsal line. Adults are medium-sized dark brown moths with complex forewings, characterized by three diagonally extending distinct white bands in the middle of two wavy stripes, hence the name Twill Nocturnal Moth.
Fruit-sucking nocturnal moths are actually a large category, and there are 18 kinds of hazards that often cause harm to citrus, of which the most common are the nocturnal moths, the nocturnal moths, the nocturnal moths, the nocturnal moths, the nocturnal moths, the nocturnal
In the early stage, the outside of the injured fruit is only a needle size prick hole, generally not easy to find, after 1 to 2 days after the damage, the wooded edge can be seen around the puncture hole, the puncture hole rots when the humidity is large, the puncture hole is slightly concave when drying, there is black dry rot, the inside is spongy, and the victim fruit is very easy to fall off.
● Most of the fruit-sucking moths occur in 2 to 4 generations a year, and most of them can reach 5 to 6 generations, and most of them overwinter with larvae or pupae.
● In August to November, adult insects harm ripe fruits at night, and September to October are the most harmful.
● Adult insects have strong chemotaxis, and the better the fruit quality, the more serious the damage.
<h1 class= "pgc-h-arrow-right" > three, inchworm class</h1>
There are 7 kinds of inchworms that harm citrus, of which the oil tung inchworm is the most harmful. Larvae bite the leaves, and in severe cases, the leaves can be eaten out, leaving only the leaf veins and bald branches, which seriously affects the growth of citrus.
● Occurs 3 to 4 generations a year, pupae overwinter in the soil, and feathering begins in early April of the following year.
● The first larva life may to June, the late June pupae, july emergence;
● Adults have phototropism.
<h1 class = "pgc-h-arrow-right" > iv, leaf curl moths</h1>
The leaf curl moths commonly found in citrus are mainly small yellow leaf curl moths and brown-banded long leaf curl moths. The young leaves, buds and fruits of citrus are often folded by spitting silk, or several leaves and buds are bonded together to form insect buds, and the leaves are bitten into missing or perforated, and the buds, young fruits and soon-to-be-ripe fruits are drilled and mothed and fall off in large quantities.
● Generally 4 to 5 generations, the 1st generation of larvae mainly harm the citrus larvae, eat on the surface of the peel, and most of the damaged fruits fall off.
● The 2nd generation larvae mainly harm young shoots and young leaves, and often spit silk to tie 3 to 5 leaves into buds.
● Citrus flowers bloom to the second physiological fruit fall stage, fruit coloring stage, for the larval bloom stage.
● Adults lurk in hidden places during the day, are nocturnal, prefer molasses and have phototropism.
<h1 class = "pgc-h-arrow-right" > five, leafminer moth</h1>
The insect uses larvae to sneak into the surface of the young shoots to paint moths, forming a white curved worm path, making the leaves curl and hard and falling off, resulting in poor growth of new shoots, affecting the tree posture and plucking. Wounds infested by larvae are conducive to the invasion of ulcer bacteria, often causing large-scale occurrence of ulcer disease. After the leaves are curled, they provide a settlement and wintering place for various pests such as red spiders and leaf curling moths, which increases the difficulty of control of overwintering pests.
Leafminer moths occur 10-15 generations a year. It is harmful at the end of April, but it can be harmful in November if there is tender tissue. From July to September, the summer and autumn shoot extraction period is serious, the young trees and seedlings are not neatly pumped, and the leafminer moth is rich in food and the time to drill moths is abundant, which is serious; after the summer shoots, the prevention and control of leafminer moths must not be ignored.
<h1 class = "pgc-h-arrow-right" >6</h1>
1. Agricultural prevention and control
Pay attention to its harm, do a good job in the prevention and control work at the young leaf stage, and ensure drug coverage with insecticide once every 7-10 days. There are conditions to wipe the buds and put the shoots uniformly, and give enough nutrition to promote the withdrawal of neatness when the shoots are released, and shorten the pest time. In winter, the garden can be cut off and burned, which can reduce the amount of insects in the coming year.
2. Physical and biological control
During the peak of spawning, natural enemies such as himbill bees and red-eyed bees are released for control.
3. Pharmaceutical prevention and treatment
Master the spraying of young larvae, the killing effect is good, and at the same time take into account the occurrence time and habits of various types of lepidoptera insect pests, such as the elderly twill moth likes to lurk in the soil during the day, so in the prevention and control of the drug, we should pay attention to the spraying of the tree and the ground together. The use of indateran + lice mite urea can be effectively controlled.
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