All plants are much less likely to get a disease if they are grown in mixtures just like the way they are in nature – like a woodland, or a meadow filled with hundreds of species. That’s because a disease might infect one plant, but it’s hard for it to spread if there are different plants nearby. But a farmers field is a huge area filled with exactly the same type of plant! This is called ‘monoculture’. So one plant gets a disease, and it spreads from plant to plant to plant until the whole field is destroyed.
But monoculture is an efficient way to grow crops so it’s hard to get away from it! We can breed varieties of crops that have ‘resistance genes’ that protect them from disease. Hopefully the work I do will help a little bit with this in the future 🙂