To people, salt is a kitchen staple. But to crops, too much of it can be devastating.

Across coastal regions and irrigated agricultural land, salt is accumulating in soils, making it harder for plants to absorb water and reducing harvests. Scientists estimate that around half of the world’s irrigated farmland is now affected by salinity to some degree.

The problem is only expected to grow. Rising sea levels can push saltwater into coastal farmland, while changing rainfall patterns and more frequent droughts are increasing reliance on irrigation. Poor-quality irrigation water and the overuse of fertilisers can worsen the problem, leaving salts behind in the soil year after year.

This is an issue because the global population is expected to approach 10 billion by the middle of the century, while demand for food continues to rise. Finding ways to grow crops in increasingly difficult conditions is becoming one of agriculture’s biggest challenges.

But plants are not passive victims. Beneath the surface, their roots are engaged in a constant battle with their environment. They sense danger, adapt their growth and deploy sophisticated strategies to survive.

Underground intelligence network

Roots do far more than anchor plants in the ground. They are the plant’s frontline, constantly gathering information about the soil around them. Every day, roots assess water availability, nutrient levels and environmental threats. When salt........

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