Author: Lu Xingbo is a researcher at the Institute of Plant Protection, Shandong Academy of Agricultural Sciences
In the past two years, the invasion of the grassland moth into our country is arguably one of the most worrying agricultural problems. The biological mobility of this "marching insect", which is highly migratory and lacks natural enemies in China, has brought great difficulties to control. In the face of the grassland moth that has been flying into the border for many years to harm crops, in addition to the application of a large number of chemical pesticides, are we really helpless? No, GM crops can beat it. So, how does GM technology achieve the goal of controlling crops against the grassland moth? Is this approach risky?
1. What is the Meadow Moth?
An agricultural pest native to the tropical and subtropical regions of the Americas - grassland night moth, after the invasion of Africa in 2016, "across the sea, over the mountains and mountains", footprints throughout the five continents of the world, in early 2019, this infamous pest invaded China's Yunnan, by October 2019 has spread to China's 26 provinces (municipalities, autonomous regions); in the same year, the desert locust originating in East Africa, flew over the Red Sea, into the Middle East and South Asia, and reached China's borders. Two kinds of agricultural pests with serious harm pose a serious threat to the security of food production in China.
As insects, the grassland moth and locusts are never picky eaters, prefer to eat almost all crops, and eat a large amount of food and waste. At the same time, their "relatives" are very numerous, they like group activities, and the wings on their backs allow them to travel hundreds of miles at night. The grassland moth, which first invaded China, prefers to eat corn, but can also eat sorghum, sugarcane, wheat, barley, soybeans and other crops, posing a serious threat to the security of food production in China. The invasion of the grassland night moth and the ravages of desert locusts in China's border countries have attracted the attention of the Chinese government and the people, and the No. 1 document of the Central Committee in 2020 is to point out by name that it is necessary to "grasp the prevention and control of major diseases and insect pests such as the grassland night moth", the Ministry of Agriculture and Rural Affairs issued the "National Grassland Night Moth Prevention and Control Program", issued a list of 25 emergency prevention and control pesticides, and urgently carried out the prevention and control test of natural enemies of insects "insects to cure insects"; in response to desert locusts, the Ministry of Agriculture and Rural Affairs, the General Administration of Customs, and the State Forestry and Grassland Administration formulated and issued the "National Grassland Night Moth Prevention and Control Program", issued a list of 25 kinds of emergency prevention and control pesticides, and urgently carried out the prevention and control test of natural enemies insects "insects to cure insects"; in response to desert locusts, the Ministry of Agriculture and Rural Affairs, the General Administration of Customs, and the State Forestry and Grassland Administration formulated and issued the "National Grassland NightCrawler Prevention and Control Program", and urgently carried out the prevention and control test of natural enemies insects "insects to treat insects"; for desert locusts, the Desert locust and domestic locust monitoring and control plan"
Harmful characteristics of the grassland moth
The grassland moth feeds on various parts of the corn for symptoms
Image from "The Occurrence Dynamics and Future Trends of the Invasion of the Grassland Nightcrawler in China"
2. Genetically modified corn can effectively control the grassland moth!
The threat of the grassland moth to agricultural production reminds us of the history of China's control of cotton bollworm in the last century. In the second half of the 20th century, in China's agricultural ecological environment, cotton bollworm rose from a secondary pest to a dominant pest. At that time, the seriousness of the harm of cotton bollworms, Jing Shenrong, the former genetic breeding research office of the China Cotton Research Institute, said, "The dustpans in the countryside go to that field like this, and the cotton bollworms can't count how many heads, how many pounds are called." With the improvement and improvement of China's pesticide system, agricultural production workers sprayed a large number of chemical pesticides in the field for the prevention and control of cotton bollworms, but soon the field cotton bollworms developed resistance to pesticides; then carried out a large number of spraying pesticides at the same time, combined with light trapping, artificial hunting, parasitic bee release and other chemical pesticides based on comprehensive control; but from 1996, China's scientific researchers cultivated the first domestic transfer Bt gene insect-resistant cotton new varieties, China's large-scale promotion of Bt insect-resistant cotton, Combined with various integrated control methods, the problem of regional cataclysms of cotton bollworms was solved. The experience of cotton bollworm prevention and control in China can provide a certain reference for the control of grassland night moth.
Transgenic and non-GMO cotton is subject to symptoms of bollworm feeding
The Bt of transgenic Bt insect-resistant cotton refers to the Bt protein, which generally refers to the protein with insecticidal activity produced by Bacillus thuringiensis. Since the 1990s, the United States, Canada, and Argentina have begun to grow genetically modified Bt insect-resistant corn for the control of lepidopteran pests such as corn borer and grassland night moth. Growing genetically modified maize is an effective strategy to address the threat of the grassland moth to the safe production of maize.
Non-GMO Corn Plants Genetically modified corn plants
Control of insect resistance effects of transgenic maize and non-GMO maize in the field
3. The use of GMOs does not produce super pests
Although improper planting methods and improper cultivation management measures for planting a single variety in large areas for a long time will also make pests resistant to GM insect-resistant crops, comprehensive prevention and control can be carried out through different control measures and no so-called super pests will be produced. Since China's independent research and development of the first transgenic Bt cotton has a history of more than 20 years, Chinese researchers have been tracking and monitoring the resistance of cotton bollworms to transgenic Bt cotton. Field monitoring found that the field cotton bollworm population still has a high sensitivity to Bt protein, from 2012 to 2013 in Henan, Shandong, Hebei did not find field resistant cotton bollworm, field cotton bollworm population resistance gene frequency is low, indicating that cotton bollworm resistance is still at a low level. Improvement through biotechnology and cultivation methods can effectively slow down the development of pest resistance and improve the efficiency of pest control, such as improving the expression of insect resistance proteins, selecting multiple insect resistance gene combinations, or building shelters. So, growing genetically modified crops doesn't produce super pests.
At this stage, China does not allow large-scale planting of genetically modified corn, but Chinese researchers are also conducting a large number of in-depth scientific experiments to ensure the safety of genetically modified organisms. As a biological means, transgenics can become one of the important ways to prevent and control agricultural pests, and together with other scientific prevention and control measures, they can make an important contribution to the safety of food production in China.
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Source: Guangming Network