First, the morphological characteristics
Monoleptahieroglyphica (Motschulsky), also known as maize biplanet long-planted leaf beetle and dimacular leaf beetle, is the main pest of corn on corn, sorghum, millet, beans, melon vegetables, fruit trees and other crops.
1. Adult: Body length 3.6 ~4.8mm. Ovate, brownish-yellow, shiny on the body indumentum, filamentous antennae, gray-brown. The base half of the elytra is black with 2 pale yellow spots;
2. Egg: oval, 0.6mm long, initial brownish yellow, the surface has a reticulated pattern;
3. Larvae: body length 5 ~ 6mm, white to yellowish white, body surface with tumors and bristles, the color of the dorsal plate of the anterior thorax is darker, there are 3 pairs of pectoral feet, and the body surface has pairs of inconspicuous hairs;
4. Pupa: length 2.8 ~ 3.5mm, width 2mm, white, bristles on the surface.
2. Symptoms of harm
Adults feed on the flesh of the leaf, leaving irregular white reticular spots and holes, affecting photosynthesis. It can also bite the filigree and affect pollination. It also eats grains during the filling stage, causing grain defects, which are easily infected by other pathogenic bacteria and cause panicle rot.
Third, the law of occurrence
Maize double-spotted firefly beetle occurs in Xinjiang for one generation per year, overwintering under the topsoil as scattered eggs, and after hatching in the soil the following spring, the larvae continue to live in the soil, mainly feeding on the roots of weeds. The adult insects that have been pupated and feathered first infested with weeds in the field edge of the field, then migrated to the corn field, and entered the adult bloom period in early to mid-July, which continued to be harmed until mid-September. This insect can fly and jump, during the day in the corn leaves and ears of activity, after being frightened quickly jump or take off, flying distance of 3m ~ 5m or even farther, adult insects have strong flying ability, there are clusters.
Fourth, green prevention and control technology
1. Deeply turn the sunburned soil and lower the overwintering base
Deep ploughing of the soil in autumn can lower the egg base of a large number of overwintering insects.
2. Eradicate weeds and destroy the living environment
Field edge weeds are the intermediate hosts of double-spotted fireflies, and the soil under the weeds is the main place for their spawning and larval growth and development, so timely eradication of weeds in the field, the ground and the canal, especially the barnyard grass, can reduce the harm.
3. Environmentally friendly chemical control
In the adult bloom period at the end of June and early July, use 20% chlorantranium benzamide (Kangkuan) suspension 2000 to 4000 times liquid or 1.8% avermectin emulsion 2000 times liquid or 5% acetamidine wettable powder 2000 to 2500 times liquid or 2.5% high efficiency cypermethrin emulsion 1500 times liquid, or 2.5% kung fu 2000 times liquid, or 50% octylthion emulsion 1500 times liquid, or 20% rapid killing butadiene emulsion 2000 times liquid, specifically treated first outside the field, and then treated in the field.
Compiled by the research team of corn diseases and insect pests of the Institute of Plant Protection of Xinjiang Academy of Agricultural Sciences