Climate change poses serious challenges for breeders. An intelligent field robot and X-ray technology help them select heat-resistant plant samples for selection. The sensors in the high-tech machine were developed by the Fraunhofer Center for the Development of X-ray Technology, a division of the IIS Fraunhofer Institute for Integrated Circuits. Phys.org portal.
Summer is getting hotter. This summer alone, Germany has experienced extreme heat, with temperatures reaching up to 40°C. The drought also affected plants.
With a sufficient supply of water, plants can be cooled by evaporation. However, they cannot do this when they are stressed by drought. That's why breeders hope to develop heat-tolerant, drought-tolerant plants that can survive on less water and still produce good crops while requiring the least possible amount of fertilizer and pesticides.
Breeders receive support from researchers at Fraunhofer EZRT, where research has been carried out for many years on technologies for determining plant phenotypes. This refers to their appearance, which includes many factors such as leaf size, leaf position, root thickness, and yield. “People have been choosing crops based on external characteristics for thousands of years,” explains Dr. Stefan Gert, head of the AMS department at the Fraunhofer Center for the Development of X-ray Technology. “We are developing technologies to objectively measure these phenotypic characteristics and optimize breeding based on these data.”
A research team led by Dr. Gert has developed DeBiFix, a field robot for agriculture. It is able to continuously take x-rays of plants. At the same time, it generates 3D images using an optical system. This is important information for the breeder - it allows him to, in fact, look inside the wheat ears or under the potato bush and determine if the variety they are growing is producing a good crop.
The most important goal of the interregional Fraunhofer smart farming project is to support breeders. Within its framework, the Fraunhofer Plant Phenotyping Technology Center opens in Triesdorf, Bavaria. At this point, Dr. Gert and his colleagues intend to develop the experience and apply it in real life.
In the laboratory room for plant phenotyping under climate controlled conditions at the Fraunhofer EZRT in Fürth, Dr. Gert demonstrates how breeders will work in the future. On a narrow conveyor belt in front of the X-ray unit, pots with various cultivated plants are arranged in neat rows. The door of the X-ray machine opens and a pot slides in. As soon as the door closes, the pot undergoes a CT scan.
“More than a decade ago, we started X-raying potato plants to get information about tuber growth,” reports Dr. Gert. “Based on the 3D x-rays, we can determine the weight of the tubers without digging them up.” This process is used for tasks such as selecting particularly heat tolerant varieties. For this purpose, the plants are placed in a laboratory under conditions of heat stress. The scan then reveals which plants are most effective at coping with stress, producing strong tubers despite the heat.
While the first CT scans could only show through thick roots and tubers, newer systems can also capture the fine underground structure of wheat roots. “Our new X-ray machine is the most advanced and powerful system for scanning plant parts underground,” says Dr. Gert.
Researchers at Fraunhofer EZRT are also doing 3D digital imaging of parts of plants that are above ground, such as leaves and ears of wheat. This data can be used not only to determine the leaf area - 3D images also provide information about the heat tolerance of the plant. Does the plant raise its leaves to protect itself from the sun? Do leaves curl due to stress?
The performance of the Fraunhofer EZRT optical plant recognition systems was clearly demonstrated in the test field of the seed company Strube D&S GmbH. In this case, the second BlueBob prototype was used, a field robot that moves independently and automatically removes weeds in sugar beet fields. Moving between the rows, he records images of all living plants using multispectral cameras.
"Through artificial intelligence the phenotype of each individual plant is analyzed and classified as either a weed or a beet plant,” explains Christian Hügel, head of the Technical Center for Seed Research in Strub.
One of the main areas of work in the new center in Triesdorf will be the processing of data obtained during phenotyping. “Our main goal is to use our technology to support small and medium plant breeders“, emphasizes Dr. Gert.