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How Fighting Weeds can Help end Poverty and Save Our Planet?

Sustainable Development Goal 1 (SDG 1)—No Poverty—is one of the 17 goals set by the United Nations in 2015, aiming to “end poverty in all its forms everywhere”. This goal seeks to eliminate the lack of food, water, and sanitation that characterize poverty. SDG 1 is about ensuring that all people’s basic needs are met for a healthy and happy life. Even though poverty has been cut in half since 2000, we still need to do a lot more to help people earn better incomes and have easier lives. Food is a basic human need. To make sure we can feed a growing population, famers need to grow more food from their crops. In Africa and other regions, weeds cause big problems for agriculture, including the loss of certain crops. Weeds can also harm the soil, worsening the damage caused to crop plants. In addition, climate change and rising global temperatures are creating more extreme weather events like droughts, which further harm the soil and plants. These threats destroy farmers’ crops, putting them, their families, and their communities at risk of hunger and poverty.

People cannot thrive if they are struggling with hunger and are unable to provide for their families. That is why removing harmful weeds helps advance SDG 1, because it helps crops grow better so farmers can provide more food, and it also helps farmers earn a fair income [1, 2]. Stopping harmful weeds from growing is closely linked to other important SDGs, too. For example, SDG 2—Zero Hunger—focuses on making sure everyone has enough healthy food and supports farming that protects the planet. This goal is also connected to SDG 13—Climate Action—which calls for urgent action on climate change and its effects on people’s lives. Finally, it is also linked to SDG 15—Life on Land—which aims to protect and restore nature and stop the damage to our environment. Can you imagine the huge difference we can make just by eliminating these harmful weeds?

The Importance of Cereals

A cereal is a grain used for food. Our breakfast foods, especially bread, are made from cereals. Cereal crops like wheat, maize, rice, sorghum, and pearl millet are some of the most commonly grown crops and are vital for human nutrition, as they provide starch, protein, and vitamins. They are also key ingredients in animal feed and serve as raw materials for industries such as poultry feed and cattle feed. Cereals play an important role in the food supply, international trade, and economic growth. Unfortunately, African farmers are facing several challenges in cereal production, including lack of money to buy farming machines and tools, bad land, drought, pests, diseases, and weed infestations. On average, the cereal crop yields in Africa are 44% lower than global yields. As a result, many African farmers experience poverty and lack of food due to reduced cereal production [1].

What is Striga and What is its Impact in Africa?

Weeds are unwanted plants that stop crops from growing well, as they compete with crop plants for space, soil, water, and nutrients. Weeds cause problems for farming, use up valuable water supplies, and can sometimes destroy entire crops. Parasitic weeds are particularly bad. These weeds survive by attaching to crop plants and stealing their food and nutrients, harming them in the process. Root-parasitic weeds—weeds that attach to the roots of other plants—have infested cereal crops in sub-Saharan Africa, the Middle East, and parts of Asia. Among these weeds, Striga plants are the world’s worst damaging ones [3].

Striga is a harmful weed that attacks cereal crops and creates big problems for farmers in Africa. Striga causes huge crop losses, costing billions of dollars every year [1]. Striga hurts two groups: small farmers, whose crops are reduced, and people who buy or sell cereals, as there is less food to go around. Striga is making hunger and poverty worse for millions of people in Africa. This parasitic weed is spreading fast across many African countries, affecting almost half of the farmland [4]. It is hard to control because Striga seeds last a long time, spread easily, and grow in large numbers.

Using Science and Technology to Solve The Striga Problem

To tackle the Striga problem, our group is researching a technology called suicidal germination. To understand this approach, it is important to understand the Striga’s complicated life cycle (Figure 1) [5]. After flowering, a single Striga plant can produce a large number of seeds that quickly build up in the soil. These tiny seeds can easily spread to new areas via wind and rainwater. Striga seeds can stay inactive in the soil for many years [6]. When conditions are favorable (hot and humid), the seeds become active. Once they detect certain chemicals from nearby crop plants, specifically a plant hormone called strigolactone, the Striga seeds germinate, developing a root-like structure called a haustorium, which allows them to attach to the crop plant’s roots. After a few weeks, Striga grows out of the soil, makes flowers, and produces seeds for the next generation.

To deal with this dangerous weed in African countries, we need to both reduce the number of seeds in infested soils and prevent further seed multiplication [7]. Our strategy uses the Striga life cycle against itself! Imagine Striga seeds as tiny, sneaky thieves hiding in the soil, waiting for a signal to wake up and steal food from crops. So, before planting a crop, our strategy is to trick the Striga seeds by sending out a fake signal, like a prank alarm clock, that awakens the seeds and starts germination. But they germinate too early, when there is no crop yet to steal food from, so they end up using all their energy and starve. This way, the seeds die before they can harm crop plants. The fake signal we send is a chemical produced in the lab that mimics the natural strigolactone hormone that crop plants produce (Figure 2). When the germinated Striga seeds die before they can attach to any crop plant, the number of seeds in infested soils decreases [8].

What are the Challenges of Suicidal Germination Technology?

Although suicidal germination is a really cool and promising technology, it still has some drawbacks. For instance, producing these artificial signaling molecules is expensive. Also, we need to find less expensive ways to apply these chemicals over large pieces of land—like special tractors or watering systems. We also need to consider time of the application of these chemicals perfectly, adding them to soil when the weather is hot and humid, just the way Striga seeds like it.

To overcome these challenges, we developed two new artificial strigolactones named MP3 and Nijmegen-1, and we collaborated with a big farming company to produce and sell them at a lower price. Using these molecules, we can successfully reduce Striga seeds in infested soils. Although these molecules seem to be safe and nontoxic, they still need to be tested further to make sure.

Using Rain to Help Suicidal Germination Technology

African agriculture faces challenges such as water scarcity, uneven fields, poor soil, and limited automation. Given these tough conditions, we created an application procedure for African agriculture (Figure 3) [7]. After rainfall on wet soil, we apply signaling molecules to start the germination of Striga seeds present in the soil. After a few days, these germinated seeds die because there are no crop plants around for them to attach to. In this way, we can lower the number of Striga seeds in the infested soils.

First, we tested this technology at King Abdullah University of Science and Technology (KAUST) in greenhouse experiments. We observed good control of Striga attack in these experiments. Next, we applied this technology in farmers’ fields in Kenya, Tanzania, Burkina Faso, and Niger. We observed a 50%-70% control of Striga germination in the fields. Thanks to our technology, the parasitic weed was controlled, and we observed good growth and yield of the cereal crops. These results show that our technology can help these countries to meet the targets of SDG 1. In addition to Striga, the chemicals we developed can be used to control other types of parasitic weeds. Additional types of chemicals can be added to enhance the effectiveness of suicidal germination technology. After suicidal death of Striga seeds, germination of remaining Striga seeds in the soil can be prevented by using still other types of chemicals.

Suicidal Germination Technology Can Help Farmers Grow More Food and Escape Poverty

In conclusion, we have come up with a simple solution to a big problem in African farming. The new method, suicidal germination technology, has shown great results by controlling Striga weeds through lowering the number of their seeds in the soil. This technology will help poor farmers to clean their soil from Striga seeds, which means they will be able to grow a lot more food and earn more money. This progress supports SDG 1 - No Poverty by giving farmers a fair chance to grow healthy crops, improve their harvests, and earn a better living, all thanks to an effective technology that helps protect their fields from harmful parasitic weeds.

Glossary

Drought: ↑ The condition of receiving very little rain for a long time, leading to water shortages.

Infestation: ↑ The state of being invaded by pests or parasites.

Crop Yield: ↑ The amount of a crop produced from a given area of land.

Parasitic Weeds: ↑ Weeds that must attach to another plant (called the host) to obtain nutrients or water, often harming the host plant.

Germination: ↑ The process by which a plant grows from a seed into a seedling.

Plant Hormones: ↑ Molecules produced within plants in very low concentrations that regulate all aspects of plant growth and development.

Strigolactones: ↑ A group of chemical compounds produced by roots of plants.

Haustorium: ↑ A rootlike structure from the root of a parasitic plant that grows into or around the root of host plant to absorb water or nutrients.

Conflict of Interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Acknowledgments

This study was supported by the Gates Foundation (grant OPP1136424 and INV-06319) and King Abdullah University of Science and Technology, Saudi Arabia. We are grateful to Research Communication, KAUST for making illustration figures of the manuscript. We would like to thank Ruben Costa and Nicki Talbot at KAUST for their invaluable support during the initial writing stage and review process, without which this collection would not have been possible. We also extend our gratitude to the KAUST Office of Sustainability and the UNDP Saudi Arabia Country Office for their dedication to raising awareness of the UN SDGs in our journey toward a more sustainable world.