green lacewing. Predatory insects, the puloptera of the insect order, are uncompromising beneficial insects for agricultural production and are often used as biological control. The body is slender, about 10 mm long, green. The compound eye has a golden glow. The antennae are elongated and filamentous. The wings are broad, transparent and extremely beautiful. It often flies among grasses and trees, laying eggs on leaves or other smooth smooth surfaces. Ovate yellow with long filamentous stalks.
In China, the number of generations of grasshoppers in a year varies from 1-4 generations, and under artificial breeding conditions, some species can reach as many as 8-9 generations a year. Although there are many species of grasshoppers that are common in China and have been experimented with in the early 21st century for biological control, there are only the following ten species, namely the great grasshopper, the lily grasshopper, the leaf-colored grasshopper, the spotted grasshopper, the sticky grasshopper, the tawny grasshopper, the melasma vermasost, the Sub-African grasshopper, the white-lined grasshopper, the common grassfly and the Chinese grassfly. In organic and green cultivation, grasshoppers can be bred in large quantities for biological control. In addition to preying on aphids, grasshoppers can also prey on leaf mites, whiteflies, mesolar insects, as well as tea silkworms, leaf curl moths, poisonous moths, and inchworm moths, which are a multifunctional predatory predators.
The yellow ones above are aphids, and the brown ones are the larvae of grasshoppers, which lay their eggs in a group of aphids to prepare food for offspring after birth
Grasshoppers have different advantages in different regions. The dominant grasshoppers in the northern cotton area mainly include Chinese grasshoppers, large grasshoppers, lisgrass grassflies, leaf-colored grasshoppers, Jincao grassflies and common grasshoppers. The common grasshopper species in Nanchang are mainly large grasshoppers, Chinese grasshoppers, common grasshoppers, Song's Tong grasshoppers, etc.; in cotton fields and corn fields, large grasshoppers and Chinese grasshoppers are the mainstays, and on fruit trees such as peaches, pears and citrus, there are more common grasshoppers, followed by large grasshoppers and Chinese grasshoppers; and vegetable fields have more large grassflies and Chinese grassflies. The adult feeding habits of grasshoppers have changed, such as Chinese grasshoppers, Asian and African grasshoppers, etc. will change their carnivorous to plant-feeding, like bees and butterflies, flying among the flowers, sucking on the pollen and honeydew of plants. At this time, the ability to eliminate pests will be lost, while other species of grasshoppers adhere to the meat-eating habit and still feed on pests, such as large grasshoppers, lily grasshoppers, etc., and can still eat more than a hundred aphids a day on average.
A female Chinese grasshopper can lay 1237 eggs in 5 days, and the lily grasshopper can lay 892 eggs. Grasshoppers in captivity conditions can further increase spawning if the light is prolonged. After the adults of grasshoppers are feathered, they must be supplemented with nutrients to lay eggs, mainly from pollen, nectar and a variety of eggs. Grasshopper larvae have the habit of killing each other, and generally have a barrier in the artificial feeding container to reduce the contact and killing between the larvae. Artificial feeding feed for grasshoppers can be made of rice moth eggs or artificially prepared flour feeds such as dry flour, honey, sucrose, etc. Liquid feed for common grass ridge larvae, mainly casein hydrolysate and soybean hydrolysate, was later refined with a series of improvements to the formulation and the nutritional aspects of the feed were analyzed. A liquid feed made of brewer's yeast hydrolysate, casein hydrolysate and egg yolk is another feed. Adult grasshoppers do not occur in diapause when under long light conditions. Therefore, when artificially raising grasshoppers, the characteristics of grasshoppers are often used to give adults 16-18 hours of long light every day, so that grasshoppers can continue to spawn and reproduce throughout the year.
Grasshoppers are more tolerant to organochlorine, permethrin pesticides, etc., but are sensitive to organophosphorus and carbamic acid vinegar pesticides; the drug resistance is stronger than that of adult insects in the juvenile stage. Microbial insecticides, plant extracts, acaricides and fungicides have no significant effect on the growth and development of grasshoppers and reproductive strength.
Urea is less lethal to adult Chinese grasshoppers, but can lead to adult sterility and is stronger against larvae and eggs
fatal effect. Taibao has a strong lethal effect on adult Chinese grass ridges. Cypermethrin trifluorothrin in pyrethroids is highly virulent to Chinese grasshoppers.
Has security . As a predatory predator, grasshoppers can effectively control pests, avoid or reduce the use of chemical pesticides, and will not have any toxic side effects on humans and livestock, high safety, will not pollute the environment, and is not conducive to the improvement of pest resistance.
Durable and extensive. Grasshoppers have their dominant populations throughout the country, reproduce quickly, and can establish a strong and sustainable population in farmland with rational use of drugs, so they can use grasshoppers to inhibit the occurrence and development of many pests for a long time. Grasshoppers have a wide range of feeding habits, can prey on a variety of pests in farmland, and are very promising as a natural enemy of pest control in agricultural production.
Has a good economy . Grasshoppers allow the growth and pest growth and pests to be mitigated, controlled, and yields and quality improved. At the same time, the use of chemical pesticides has been reduced, the cost has been reduced, and the amount of pesticide residues has been reduced, and the quality and yield of crops have been improved.
China's research and technology in the breeding of grasshoppers is relatively backward, which restricts the progress of biological control using grasshoppers in China. The traditional artificial breeding method is expensive, far more than chemical control, and has an impact on mobilizing farmers' enthusiasm for use, and cannot be promoted and used on a large scale.
However, in the current hot background of the green and organic food market, biological control is gradually being valued by growers, is artificially farmed grasshoppers a good entrepreneurial outlet?
Measures to improve the biological control effect of grasshoppers: improve the ecological environment, protect the vegetation environment of grasshoppers, and facilitate their reproduction. Strengthen field management, transform production conditions in a direction conducive to crop growth and grasshopper occurrence, and give full play to the advantages of natural control in the field. It is artificially collected to protect overwintering and released in the field after spring, which is mainly promoted in the north. Coordinate the contradiction between biological control and chemical prevention, promote biological insect control; establish the concept of comprehensive control of insect pests, and use low-toxicity and highly selective pesticides to reduce the killing and injury of grasshoppers.
Resources:
Shao Zhenfang, Yin Wenbing, Chen Jianhua, Wang Zeqing.. Research progress on the application of grasshoppers in biological control of insect pests[j]. Modern Agricultural Science and Technology, (3), 171-174.
ZENG Fanrong,XU Xuenong,WANG Endong. Quality Control Methods for Natural Enemy Insects[j]Chinese Journal of Biological Control, 34(2)324-326
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