Breakthrough in plant research: New insights into barley breeding!

Breakthrough in plant research: New insights into barley breeding!

Biologists at Heinrich Heine University Düsseldorf (HHU) have made significant progress in research into the floral architecture of grasses. These innovations could play a key role in improving agricultural production. In one in the specialist magazine Nature Communications In the published study, scientists identified a specific peptide and receptor that control the growth of inflorescences in grasses, including barley.

The grasses have a variety of inflorescence forms, with barley being characterized by its simpler inflorescences, which form their grains on a short axis, the “rachilla”. The studies are based on the conclusion that the shape of the inflorescences is determined early in plant development by the size, position and lifespan of the meristems. A signaling pathway that regulates the activity of certain meristems in barley has now been discovered.

Influence of peptides and receptors

The peptide HvFCP1, secreted by rachilla cells, plays a central role in this process. It interacts with the receptor HvCLV1 to control meristem growth. Professor Dr. Jürgen Schmid and his team found that mutations in the genes for HvFCP1 or HvCLV1 cause the inflorescences and rachillae to become enlarged, resulting in multiple flowers and grains from one rachilla. Interestingly, these mutants are similar in architecture to wheat inflorescences.

The results of this research lay the foundation for new breeding approaches that are based on genome editing and could thus enable faster production of high-yielding plant varieties. The work is part of the “Cereal Stem Cell Systems” (CSCS) project funded by the German Research Foundation and the Cluster of Excellence for Plant Research CEPLAS at the HHU.

Additional research results on ear formation

In parallel to these developments, an international research team led by the IPK-Leibniz Institute reported on the mechanisms of ear formation in barley. The results, published in Current Biology, show that meristem activity and differentiation are crucial factors for inflorescence architecture. The characterization of a particular mutant, called barley ear flo.a, confirms findings that the gene HvALOG1 plays a crucial role in the regulation of the ear meristem and boundary formation between floral organs.

Mutations in HvALOG1 lead not only to additional spikelet formation but also to the fusion of floral organs. These findings are important in comparison to wheat because the identification of the wheat gene ALOG-1 and its function in a parallel study shows how closely these research areas are interconnected.

The influence of technical breeding

The studies mentioned above illustrate the long-term development in plant breeding, which has been looking for ways to increase genetic variation for decades. While the selection of new plant varieties with desirable traits has traditionally been limited by natural genetic changes, newer techniques such as mutation breeding offer promising advances. Since the 1950s, breeders have used methods such as ionizing radiation and chemicals to introduce genetic modifications.

Mutation breeding is considered a conventional breeding method and is not subject to genetic engineering law. These methods have led to the development of successful crops, resulting in over 3,000 X-ray or gamma-related mutant varieties listed in the Joint FAO/IAEA database. Some examples of successful varieties are:

• Gerstensorte „Golden Promise“ (hoher Ertrag, verbesserte Mälzung)
• Hartweizen (für Brot und Pasta)
• Krankheitsresistente japanische Birne
• Dunkelrosa Grapefruit
• Halbzwergiger Reis
• Krankheitsresistente Bohne
• Erdnüsse mit festeren Schalen
• Sorten von Erbsen, Baumwolle, Pfefferminze, Sonnenblumen, Grapefruit, Sesam, Bananen, Maniok und Sorghum.

These successful developments in plant research are directly related to current studies on floral architecture, which not only generate scientific interest but could also have important consequences for future agriculture.