Technical Yearbook 2023

JULY

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Managing for optimum root health By Prabashnie Ramouthar

Plant health is dependent on root health which is ultimately dependent on soil health. This article is republished from the proceedings of the Soilborne Plant Disease Symposium 2022, with permission from the author and the organising committee. Roots are the support system of a plant. They anchor the plant and absorb water and nutrients from the soil. They are also the transport system of this water and nutrients throughout the rest of the plant. Without a healthy root system, plant uptake is thus compromised and as such plant health is compromised. It is thus imperative that healthy roots are grown, developed, and maintained. Within an agricultural system, roots are often grown in soil. It follows that to maintain healthy roots, roots must grow in healthy soil. Soil health is a combination of physical,

chemical and biological soil health. Optimum management of each facet of soil health will contribute to optimum root development. To this end, managing for optimum root health will be discussed in the context of optimum management of each facet of soil health, with a focus on biological soil health, the soil food web and the contribution of nematodes to the soil food web. Physical soil health The physical soil properties that affect root development are soil texture, depth, structure and temperature, as well as compaction and water availability. Soil texture, depth, structure and temperature (to a degree) are for the most part inherent soil properties and management regimes generally do not directly affect these properties. Compaction and water availability (in irrigated crops), however, can be managed to achieve optimum root development. Soil compaction occurs when soil particles are pressed together. This reduces the pore spaces between the soil particles. As a result, a physical barrier to root development is created

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TECHNICAL YEARBOOK 2023