The green blind bug control technology achieves the purpose of effective control of fruit trees while reducing the application of chemical pesticides
Zhou Pengcheng and others
Green blind bug is a prickly pest of a variety of host plants in the genus Hagfish, and has become one of the main pests on grape and date trees in China, and will cause harm to peach trees, apple trees, cherry trees and pear trees. According to reports, in 1997, green blind bugs were harmed, causing 20 to 30 percent of jujube trees in some jujube districts in Shandong and Hebei [Jishan Huayao self-media network first published]; in 2001, green blind bugs were harmed, causing a damage rate of 30%-60 percent of jujube trees in Yuci District, Jinzhong City, Shanxi Province; green blind bugs caused 80 percent of jujube trees in Lubei Zao District for three consecutive years from 2003 to 2005; in 2008, green blind bugs were harmed, creating a high rate of 88.7 percent in winter jujubes in Tianjin City; and green blind bugs in 2013 and 2014. As a result, the jujube forest with an area of 53,300 hm2 in Jia County, Shaanxi Province, was reduced by 60% and 75% respectively.
In recent years, the green blind bug has surpassed the heartworm and become the most serious pest of jujube trees in Shanxi, and in the years when it is seriously harmed in Linxian County, Shanxi, the damage rate of jujube production is 80% to 100%. At present, the control of green blind bugs mainly depends on chemical control, but due to the strong activity ability of green blind bug larvae, adult worms have strong flight ability, resulting in increased pesticide dosage and use times in the chemical control process, which in turn aggravates the pesticide residues of fruits; at the same time, due to the long-term use of chemical pesticides, green blind bugs have developed resistance to a variety of agents. To this end, this paper summarizes the integrated control technology of pesticide reduction of green blind bugs in fruit trees for reference.
1 Agricultural control
Agricultural control is an important means of pest control, through different plant intercropping, rational layout, increase the ecological diversity of farmland, and then through ecological control means to effectively control pests, such as cotton field maize, sorghum can effectively control cotton bollworms. The green blind bug is a multi-host plant insect, its preference for different host plants is different, studies have shown that the green blind bug host plant involves 38 families and 147 species. By inducing plants to control pests, it has the advantages of simplicity and environmental protection, and the purpose of continuous control of pests can be achieved. [Yoshiyama Huayao self-media network debut]
Green blind bugs have different degrees of preference for different host plants, and their preference for alfalfa, hyacinths, and legumes is significantly stronger than other plants. In the orchard, the ecological niche differences of different plants can be used, for example, the 0.5 m wide amaranth, hyacinth, legumes, etc. can be planted as a trap belt through the checkerboard planting method, and the green blind bugs in the orchard can be attracted to these trap belts, and then chemical agents are sprayed to concentrate on killing the green blind bugs.
2 Biological control
Biological control is an effective measure to control pests, especially insect pheromones, which have the advantages of environmental protection and friendliness to natural enemies. At present, China has developed a sex lure core of green blind bugs, the main components of which include 4-oxo-trans-2-hexenal and butyric acid -trans-2-hexene esters, which have been proved through field experiments that they have a good lure effect on green blind bug males. At present, the control means of sexual pheromones on green blind bugs are mainly based on adult traps, and the male adults of green blind bugs are trapped by a large number of hanging traps in the field, reducing the male-female ratio and adult base of green blind bugs in the field, thereby reducing the insect population base of the next generation and gradually achieving the purpose of controlling green blind bugs. For example, in the jujube garden, the trap suspension height is 1 .8m, and each trap is equipped with 3 sexual cores, which is suitable for hanging 75 to 120 / hm2; the hanging height of the trap in the vineyard is 1.5m, each trap is equipped with 2 sexual cores, and it is advisable to hang 75 / hm2.
In addition, green, yellow and blue armyworm plates also have a certain enticing effect on green blind bugs, especially green lure plates. By hanging the core in the orchard, the spawning volume of the first generation of green blind bugs in the orchard can be reduced, thereby reducing the occurrence base of the next generation of green blind bugs. When hanging swatches in the jujube garden, the lower edge of the swatch is 1.6 to 1 .8m from the ground, hanging 1 swatch every 4 m; in the vineyard, the lower edge of the swatch is 1.2 to 1.5 m from the ground, and 1 swatch is hung every 4 m.
3 Chemical control
Studies have shown that the overall number of blind bugs in China's farmland has increased by 12 times from 1997 to 2010, although there are fewer reports on the resistance of green blind bugs in China, but it has clearly shown the problem of declining the control effect of chemical pesticides. Especially due to the strong activity of green blind bugs, the current control of green blind bugs has poor efficacy of spraying chemical pesticides, especially for adult insects, resulting in the use of pesticides in orchards many times, and because the reproduction rate of green blind bugs is relatively fast, resulting in its gradually stronger resistance, resulting in a large amount of pesticide waste, the orchard soil and ecological conditions have also caused great damage. Since green blind bugs are sucking pests, how to control the pests through the conductivity of the systemic insecticide, by changing the application method, while reducing the amount of pesticides used, has become the top priority of the control of green blind bugs in orchards. Through indoor virulence and field spray tests, it was found that neonicotinoid insecticides have a better control effect on green blind bugs than other agents, and they have a strong systemic conduction effect. Therefore, the root application of neonicotinoid insecticides such as imidacloprid and thiamethoxazine will become an effective means of preventing and controlling green blind bugs. According to the pest law of green blind bugs on jujube trees, the time of the first root application of neonicotinoid insecticides in the jujube garden should be 15 days before the bud of the jujube tree and 7 days before flowering for the second time. The root application amount is consistent with the spray application amount. The application method dissolves the neonicotinoid pesticide in water, the water consumption is 7.5t/hm2, and the pesticide solution is filled into the ditch by ditching on both sides of the jujube tree, and then the pesticide ditch is buried.