Overview
During the process of our iGEM project, we encountered some problems. We need to do human practice to solve them. We interviewed some experts to get the background of locust plague and existing locust prevention measures.
·Communication with Bureau of Agriculture and Rural Affairs, Handan
We interviewed Meixiang Cui, an expert and a grassroot worker on plant pest prevention. She has been engaged in prevent locust plagues for more than 20 years.
Q: What principles we should follow when we try to prevent the locust plague?
A: Sustainable development and environmental protection are the most important one.
Q: What is the criterion of controlling locust plague?
A: The control standard for prevent the locust plague is 0.5 migratory locusts per square meter and 5-10 migratory locusts per square meter.
Q: What food do locusts usually feed on?
A: Locusts mainly feed on gramineous plants, such as wheat, corn, sorghum, rice, millet, reed, barnyard grass and other plants. They also feed on dicots such as soybeans when they are hungry.
Q: what are the current measures of controlling locust plague?
A: The current governance method is mainly to use the power grid and broom to drive them away, or try to plant crops that locusts don't like to eat. The most effective way is using Emamectin Benzoate insecticide and beta-cyfluthrin to kill locusts.
·Communication with Hebei Forestry and Grassland Administration
To get the information about the use of chemical pesticides and biology control, we had a telephone interview with Huanqiang Zhang, a researcher from Hebei forestry and Grassland Administration.
He introduced us the advantages and disadvantages of these two measures respectively. The chemical pesticides, such as cypermethrin, have low cost and good effect on locust plagues, but they will pollute the environment and make the soil unsuitable for growing crops.
The biological control measures have a better specificity on locust and they are eco-friendly. But the price of biological control is not cost-effective for farmers. After listening to our project, he stated that our idea of preventing locusts swarming is a completely new to the solve the problem. It would be promising. They also reminded us to ensure the pheromone are safe to the environment and only work on the locust.
Integrate human practice
·Communication with Institute of Plant Protection, Chinese Academy of Agricultural Sciences
We went to Institute of Plant Protection, Chinese Academy of Agricultural Sciences. In the meeting room, we interviewed Professor Zehua Zhang. He is an expert on pest prevention in the national pasture industry. He has published more than 80 papers. Professor Zhang's research field is the locust monitoring and prevention technology, which fits our research. we consulted him several questions.
Q: Is it feasible to avoid the occurrence of locust plagues by preventing the swarm of locusts?
A: It cannot be completely avoided. The swarm of locusts is actually a phenomenon of locust migration. The destruction of pheromone has a good effect on long-distance areas, which means, it can make the affected area smaller. However, it does not have much significance for locust plagues have small range.
Q: Will the degradation product of the experiment have other effects on the locusts?
A: If locusts are affected, they will exhibit special behaviors. For example, locust swarms isolate changed types of locusts, change their range of activity (flying on the edge of the swarm), outlier, change phototaxis, and decrease fertility.
Q: Is it necessary to study locusts at different stages (3rd, 4th, 5th instar)?
A: Yes. Among these three instars, the 3rd instar is equivalent to the period from human children to youth, and the 5th instar is equivalent to the period from youth to adulthood. These two stages of locusts will have high observation value.
Q: Is aggregation only manifested in adults? Will the larvae swarm?
A: Yes, it is manifested from larvae to adult stage. The scattered or colonized type is restricted by density and has nothing to do with the insect age.
Q: What indicators should we use to judge the success of locust plague prevention?
A: An important governance standard is when reaching 15 heads per square meter or more, emergency treatment is needed. The focus of governance is to prevent migration and proliferation.
After investigation, professor Zhang said that breaking down pheromones is a feasible way to prevent locust plagues. He also reminded us the destruction of pheromone has a good effect on long-distance areas. For example, some locusts will swarm, then get across many countries or even whole continent. That will cause widespread famine or starvation. And the solitude or gregarious type is determined by density and has nothing to do with the insect age. Therefore, using pheromones is a valid way to achieve our goal.
In the future, we want to improve our project by doing quantitative modeling of the enzyme activity to evaluate the decomposition efficiency and practical value of the program on the target molecule. And we will install all the core components together. We also designed a mobile pesticide sprayer. The main idea is to achieve the automation of pesticide sprayer and the complete liberation of replenishment.
