Team:CAU China/Description

Background


The locust plague is a frequent natural disaster in the world. The area where locusts occur reaches 46.8 million km2, and 1 square kilometer is roughly equivalent to the area of 250 football fields. Under suitable conditions, the population of locusts grows very rapidly, 1 km2 can contain 150 million locusts, which can be described as covering the sky and sun. Current methods of locust plague management, according to FAO, locust plague is an indicator of climate warming, so the fundamental measure should be to improve the environment. But in the short term, there are mainly two types: spraying chemical pesticides and biological control. However, chemical pesticides are very harmful to people and the environment. Biological control is mainly based on the spraying of Metarhizium acridums spores. Although it does little harm to the environment and humans, it takes effect slowly which cannot replace chemical pesticides. In order to explore a greener and better biopesticides for locust, CAU_China team developed a project: Abaddon Remedy, according to Bible that Abaddon leads his locust army and brings disaster to the world. Inspired by this, we named our project as Abaddon Remedy, which means a solution for Abaddon, trying to provide a new biopesticide for locust management.
our solution


RNAi is a cellular mechanism that likely evolved to protect eukaryotes from RNA viruses. Double stranded RNA (dsRNA) can activate the RNAi pathway. There are two sources of dsRNA: One is endogeneous pathway, which is miRNA pathway. The other is siRNA pathway that RNAi takes effect by exogenous dsRNA. dsRNA will be cleaved into 20–30 nucleotide duplexes by Dicer. These nucleotide duplexes are assembled onto the catalytic component ARGONAUTE and a single guide strand is incorporated into the RNA induced silencing complex (RISC), which binds to highly complementary mRNAs and then mediates degradation of the endogenous transcript. Our solution is to activate the RNAi pathway in locust, dsRNA can be delivered to locusts and silence target genes expression, which lead to death of locust at last. Our target locust is Locusta migratoria and we proposed 2 technics against L. migratoria. To learn more about our two technics, click pictures below and see our method.
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Improving current M. acridums virulence ability

According to former people’s research, M. acridums has been tested and found to be effective on locust management. But it has a limitation on locust management that is time-consuming on locust killing. We combined M.acridums with RNAi, improving its virulence ability so as to shorten the killing time.

Transforming engineering yeast

Here the yeast refers to Sacchromyce cerevisiae, we use S. cerevisiae to produce dsRNA, and it can deliver dsRNA to locusts by oral delivery, and the dsRNA will activate RNAi in the locusts, efficiently silence the expression of related genes to kill the locusts. Finally, S. cerevisiae can be packed into dry yeast powder, which is convenient for transportation and storage.

After getting the product, the local farmer can spray it to the farmland in either form of liquid or dry powder. Or the farmer can continue fermentation, after secondary production, the farmer can get more yeast and then spray them to farmland. Yeast biopesticide has been successful in fruit flies and Anopheles larvae.

Because the target developmental stage of the yeast biopesticide M. acridums are overlapped, we innovatively combine these two solutions: With complementary advantages, Abaddon Remedy can kill locust more efficiently by doing both

the same time, the ones who never yawn or say a commonplace thing, but burn, burn, burn like fabulous yellow roman candles exploding like spiders across the stars.