The key is in the fuzzy coat of hairs on the roots of plants says Professor Liam Dolan. We have identified a growth control mechanism that enables these hairs to find their way and to elongate when their path is clear.Root hairs explore the soil in much the same way as a person would feel their way in the dark. If they come across an obstacle, they feel their way around until they can continue growing in an opening. In the meantime, the plant is held in place as the hairs grip the soil.
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In nutrient poor soils such as in parts of Australia and sub-Saharan Africa, plants have adapted by producing more root hairs. A better understanding of this adaptation will allow the development of crops able to grow in inhospitable environments.