Thanks, climate change Water scarcity and increasingly unpredictable weather patterns threaten global food security. The United Nations estimates that 1.84 billion people — nearly a quarter of humanity — lived under drought in 2022 and 2023. Prolonged drought leads to famine. In 2022, drought left almost 23 million people in food insecurity across the Horn of Africa. As of April 16, 2024, 17.9% of the lower 48 United States is officially in drought. In response, the worldwide agriculture sector is experimenting with new ways to boost drought resilience and maintain food production. - Like coffee for plants Biostimulants are substances that improve a plant’s ability to resist environmental stress without altering the plant’s genetic makeup. Chitosan is a biostimulant derived from chitin — a fibrous substance found in the outer shells of crustaceans, certain insects, and the cell walls of mushrooms! - The benefits Chitosan can improve plants’ drought resistance by raising water absorption capacity and reducing water usage — without adverse effects on biomass production and yield. This is thanks to chitosan’s ability to form cells and films that bind with various substances. - Replacing shellfish Most commercial chitosan comes from shellfish, which leads to concerns about the environmental impact of overharvesting and potential allergic reactions for consumers. - Here fungi go saving the day again Thankfully, mushrooms can also produce the chitin for chitosan without the use of crustaceans. Researchers found that plants enriched with mushroom-derived chitosan tolerated drought conditions better than untreated plants. - But … how? In this recent study, mushroom-based chitosan helped plants develop longer, denser roots to take in deeper water. The chitosan also enhanced photosynthesis capability, so the plants still produced energy for growth despite water shortages. Stressed plants produce harmful molecules that damage cell function. Chitosan helped neutralize the effects of this process to keep cells healthy. - Optimization While further research is needed to explore and optimize chitosan applications, the implications are massive for making crop production more viable in drought-stricken regions.