Dolycoris baccarum
Also known as fine hairy bugs, melasma bugs, spotted horned bugs, and arthropods
It is distributed as Dolycoris baccanum Linnaeus., a genus of hemiptera, in the family Bugs. It is harmful to tobacco, soybeans, cotton, peanuts, mung beans, wheat, corn, millet, cabbage, kale and other crops, and to paulownia, apples, pears and other seedlings. In recent years, there has been a trend of aggravation, which occurs in all provinces and regions of the country, and is one of the most widely distributed species of bugs.
When the pest characteristics are tobacco, the adult and nymphs suck sap on the young leaves, young stems, flowers and young fruits at the top of the tobacco, causing the upper leaves or the entire heart leaves to wilt and droop, and then turn brown and die, affecting the normal growth and development of the tobacco plant and the yield and quality of flue-cured tobacco.
Occurrence of regular annual l to 4 generations, Jilin 1 generation, Liaoning, Inner Mongolia, Ningxia 2 generations, south of Huanghuai 3 to 4 generations. Adult insects overwinter under bark, wall crevices, and weeds, and begin to move at an average temperature of 14 to 15 °C in the following spring. There are three generations per year in Xuchang Tobacco District and Anhui Tobacco District in Henan, and the occurrence period of adult insects in Jiongtian is from late May to mid-July, from early July to early September, and from mid-August to November. In the 3rd and 4th generation areas, the overwintering adults first appeared in April, and entered the first generation of spawning peaks in early May, and the eggs were mostly laid on wheat, fruit trees and weeds. From April to May, it is mainly wheat, and in mid-May, a generation of adult insects begins to migrate to the fields
Eggs, after harvesting wheat in early June, a large number of adult insects in the wheat field moved into the tobacco field, which is the most serious period of tobacco damage, and in mid-to-late June, it entered the peak of egg laying, and the newly hatching nymphs were harmful to tobacco. The second generation of adult insects began to appear in July, and entered the peak period in mid-to-late July, and the tobacco continued to be harmful before it was capped, and after the tobacco was topped, the adult insects moved to the corn field for pest. The third generation of eggs appears in large numbers in late July, and after the autumn crop is harvested, the adults begin to migrate into vegetable fields or fruit trees to continue feeding, and the adults gradually overwinter by November. Adults are agile, able to fly and climb, and mostly lay eggs on the leaf surface or on the back of the leaf and on the young stem, and the eggs are laid in blocks.
Prevention and control measures
(1) In mid-June, when the adults are in full bloom, manual hunting and egg removal are carried out, and the nymphs that have not yet dispersed in the first hatching are concentrated. Strengthen the management of tobacco fields, the first generation of adult insects for the peak of the pest in time to top, reduce their pest sites, the number of insect mouths fell rapidly.
(2) The first generation of adult insects into the human field, each hundred plants have 26 to 30 insects and the young nymph blooming period before the bud of the tobacco plant, spray 10% cis cypermethrin emulsion 1000 times liquid, or 20% cypermethrin emulsion 1000 times liquid, or 70% malathion emulsion 1500 times liquid, or 20% imidacloprid soluble liquid 2000 times liquid, or 26% chlorofluoropyrimidine 4000 times liquid, etc. Spraying liquid per mu is 45 to 60 kg.