Gene identification and functional analysis of high tillering mutants in barley

• Applicant: Professorin Dr. Maria von Korff Schmising
• Subject Area: Plant Breeding and Plant Pathology ; Plant Genetics and Genomics
• Term: from 2017 to 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 386675672

• Final Report Year: 2025

Final Report Abstract

Cereal crop yield is influenced by the number of tillers (side shoots) and the number of seeds per spike. Both traits have been modified during the domestication of barley and wheat. The wild forms are characterized by high and asynchronous tillering, while the cultivated forms show low synchronous tillering. Domestication-related changes of the spike included the failure of the spike to disarticulate and (ii) altered spikelet fertility. Tiller number and seed number per spike are often negatively correlated which complicates the improvement of overall yield. Consequently, a fundamental understanding of the molecular mechanisms affecting inflorescence and shoot architecture is important to improve yield. The overall objective of this project was to identify and characterize the genes that affect both tiller and seed number in barley, a model system for small-grain cereals. We used high and low-tillering mutants to investigate the genetic and molecular correlations of shoot and inflorescence architecture. We proposed three main objectives; (1) identification of the causal genes underlying tillering mutants; (2) functional characterization of these mutant loci by microscopic phenotyping and whole transcriptome analysis of developing shoot apical meristems (SAM) and axillary meristems (AM, tillers); (3) analysis of natural variation of the candidate genes in a diverse set of wild and cultivated barley genotypes. Overall, the proposed project revealed novel genetic and molecular components controlling shoot and spike architecture and thus provided novel insights into the molecular basis underlying the trade-off between seed and tiller numbers.

Publications

• early maturity 7 promotes early flowering by controlling the light input into the circadian clock in barley. Plant Physiology, 194(2), 849-866.
  Helmsorig, Gesa; Walla, Agatha; Rütjes, Thea; Buchmann, Gabriele; Schüller, Rebekka; Hensel, Götz & von Korff, Maria