Melon silk borer is the main pest of melon vegetables in central China. Young larvae eat leaf flesh on the back of the leaves of melon vegetables, so that the leaves are gray and white spots, and after 3 years of age, they spit silk to conjugate the leaves or young shoots, hide in them for feeding, so that the leaves are perforated or absent, and only leaf veins are left in severe cases; they also moth into the fruits and stems, which seriously affects the yield and quality of melons and fruits. In the late summer and early autumn, the temperature and humidity in the facility greenhouse are suitable, the peak period of melon silk borer spawning is highly consistent with the melon and vegetable melon period, the food is sufficient, coupled with the reduction of natural enemies, resulting in serious occurrence of melon silk borer in the area, if not timely and effective prevention and control, it is easy to form a large outbreak situation.
The occurrence characteristics and control methods of melon silk borer are compiled as follows:
1. Occurrence characteristics of melon silkworm borer
Melon silk borer, oligo-eating pest, the main pest of melons, the south is heavier. The first leaf tips, the leaves are three years old, the leaves are vines and fruit stems, and the holes are missing.
Note: Melon silk borer belongs to the lepidoptera borer family, also known as melon silk borer, melon borer, melon borer, north China, central China, south China, east China, southwest China are distributed, mainly harmful to a variety of melon vegetables, but also harmful tomatoes, eggplant and so on. Young larvae eat leaf flesh on the leaf back of melon vegetables, so that the leaves are gray and white spots, and after 3 years of age, they spit silk to conjugate the leaves or young shoots, hide in them to eat, so that the leaves are perforated or absent, and only leaf veins are left in severe cases; they also moth into the fruit and stems, which seriously affects the yield and quality of melons and fruits.
Plant damage
The buds are killed
2. Morphological characteristics of melon silk borer
Adults are medium-sized, black-headed, black-breasted, with a white belly and interspersed black bands. At the end of the abdomen, yellow-brown hairs, males in bunches, females fan-shaped. The four wings are flat, triangular, black framed, and transparent in white. Pale yellow eggs, oval flattened, brown pupa covered with cocoons, pointed thin and smooth. Mature larvae, brown-headed green carcass, sub-dorsal longitudinal line, milky white broad type.
Note: Adult insects are 10 to 11 mm long, with a wingspan of 25 mm, head, thorax black, white abdomen, wings and feet, yellow-brown hairs at the end of the abdomen, female hair clusters are separated left and right, and males are not separated. When the adult leaves are still, the anterior and posterior wings are flattened in a triangular shape, because the leading and outer edges of the forewings, the outer margins of the hindwings, and the sections 1, 7, and 8 of the abdomen are black broad, so the entire body shows the distinctive features of black border and white transparency in the middle. The eggs are flat, oval, yellowish, and have a reticulated surface. The old mature larvae are 23 to 26 mm long, the head and anterior thorax dorsal plate are light brown, the thorax and abdomen are grassy green, and the sub-dorsal line is two wide milky white longitudinal bands, and the valves are black. The pupa is about 14 mm long, yellow-brown and covered with a thin cocoon.
Guadallane borer young larvae
Old ripe larvae of the melon silk borer
Melon silk borer pupae
Melon silk borer adult
3. Life habits of melon silk borer
Four to six generations, overlapping occurrences, old ripening with pupae, surface overwintering. Feathered in April, in May it begins to flourish, likes warmth and humidity, and summer is heavier. Diurnal and nocturnal, strong phototropism, spawning and tenderness, leaf dorsal scattered. Three-instar curly leaves, five-year-old pupate, white thin cocoon, in the soil inside the leaves.
Note: Melon silk borer can occur for 4 to 6 generations a year, with old mature larvae or pupae overwintering in dead leaves or topsoil, feathering at the end of April of the following year, larvae begin to be pest in May, and a large number of occurrences occur in July to September, overlapping generations, serious harm, and entering the wintering period after November. Adults are nocturnal, latent during the day, and have strong phototropism. Female moths lay eggs on the back of the leaves, scattered or several grains together. The larvae are 5 years old, the hatching larvae are clustered, begin to bite on the back of the leaves, be frightened and spit silk drooping and transfer to other places to harm, after 3 years of age spit silk curl leaves to feed, until the larva matures, that is, in the curly leaves, deciduous leaves or rhizosphere topsoil, as a white thin cocoon pupa. The egg stage is 5 to 7 days, the larval stage is 9 to 15 days, and the pupal stage is 7 to 9 days.
4. Prevention and control strategies
4.1. Agricultural prevention and control
After harvesting, cultivate the land in time, dead branches and leaves, collect and process.
4.2. Physical prevention and control
Phototropism, to be utilized. Sex seducers, frequency vibrating insect lamps. Greenhouse in the shed, insect net anti-insect. Artificial removal, curly leaf characteristics.
Note: In places with a large area of melon vegetables, from May to October of each year, use 2 melon silk borers per mu, or hang 1 Jia multi-brand frequency vibration insecticidal lamp per 3 hectares to trap adult insects. Advocate the use of insect nets in large and middle sheds to control melon silk borer and cure cucumbers. Roll leaves, egg masses, or leaves with clusters of larvae are manually removed to eliminate some of the larvae.
4.3. Biological control
Natural enemies, protective utilization, biopesticides, actively promoted.
Note: It is optional to apply borer yellow red-eyed bee to control melon silk borer, in addition, in the early stage of larval occurrence, timely removal of curly leaves, placed in the predator protector, so that parasitic bees and other natural enemies fly back to nature or melon fields, but pests remain in the protector to concentrate on destroying some larvae. Spray 16,000 units of Thuringiensis (Bt) wettable powder 800 times liquid, or plant-derived pesticide 1% neem emulsion 750 times liquid, 2.5% rotenone emulsion 750 times liquid, 3% matrine aqueous agent 800 times liquid for spraying.
4.4. Chemical control
Conventional pesticides, fast and effective, conventional dosage, uniform and thoughtful. New varieties, better prevention, medicine to rotate, insects to treat small.
Note: Before seedling colonization, the seedbed can be sprayed with 10% cyanoxamide dispersible oil suspension 2000 times liquid. In the shed, the spray treatment is carried out from the peak hatching of melon silk borer eggs to the 3rd instar larval stage. It can be controlled by using 10% bromocyanidamide dispersible oil suspension 1500 times liquid, or 10% fibroxa biamide suspension 2500 times liquid, or 1.8% avermectin emulsion 1500 times liquid, or 20% chlorantraniliprox 5000 times liquid, or 15% indicosamide suspension 1000 times liquid. Different pesticides should be used alternately, and the pesticide safety interval should be strictly mastered. Generally, spray once in about 7-10 days, spray 2 to 3 times, spray the liquid evenly on the back of the leaf, choose morning or evening, and pay attention to the rotation of medication.
Author: Vegetable Guard, Si Shengyun, Yang Fan