The depths of the ocean are probably better explored than the finely branched roots of plants in the ground. It is the roots that decide how well corn, beets or other plants absorb water and nutrients from the soil. So, to some extent, they can help explain how much the farmer needs to irrigate or fertilize. Therefore, roots are an important factor in the breeding of drought-tolerant or nitrogen-efficient new plant species.
How well do plants cope with stress?
In the KWS research department, the Australian Benjamin Gruber and his colleagues explain how root growth can be observed, assessed and quantified. His goal is to test hundreds of plants in a short period of time, to see how well they cope with abiotic stress such as drought or lack of nutrients. This is one of the prerequisites when identifying new plant genes that can support stable yields and drought tolerance. Both are major breeding goals at KWS.
Observing roots and their growth in detail is not trivial: 10.76 square feet of grain field often contains 31 to 60 miles of roots (about 25 to 37 miles for corn, and 12.4 to 31 miles for sugarbeet). Sugarbeet roots protrude up to 16.4 feet deep into the earth. The finest root hairs are consistently thinner than a human hair. How can you achieve an accurate picture?
Dig, rinse and measure
A proven approach with corn follows the comparatively simple, and aptly named “shovelomics” approach: The plant with the root still on it is simply dug up during this “shovel research” and the soil is thoroughly rinsed off. Then, the root can be optically measured with cameras and software. From multiple images, specialists in image analysis and bioinformaticians calculate the number and thickness of the roots and their angle relative to the stem of the plant.