Wenyu Yang , Chunxiang Ma

Modern Agricultural Research Center, Cuixi Academy of Biotechnology, Zhuji, 311800, Zhejiang, China
Author    Correspondence author
Triticeae Genomics and Genetics, 2025, Vol. 16, No. 3   
Received: 09 Mar., 2025    Accepted: 21 Apr., 2025    Published: 06 May, 2025

This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

 Presence/absence variations (PAVs), a form of structural genomic variation, play a critical role in shaping phenotypic diversity in plants, including crop species like barley (Hordeum vulgare), which serves both as a globally important cereal crop and a model organism for genomic studies. In this review, we examined the molecular mechanisms underlying PAV formation, such as transposable element activity and large-scale deletions, and highlighted recent advances in technologies-including pangenome assemblies and high-throughput sequencing-that have enabled the comprehensive detection of PAVs. We further discussed the distribution patterns of PAVs among landraces, cultivars, and wild relatives of barley, emphasizing their evolutionary significance in domestication and adaptation. Functionally, PAVs were found to influence key agronomic traits such as disease resistance, abiotic stress tolerance, and yield-related characteristics. The integration of PAV knowledge into modern breeding programs was explored, with a focus on marker-assisted selection and pangenome-based strategies, including a case study on improving heat tolerance through PAV-informed breeding. Lastly, we considered the potential of combining PAV analysis with multi-omics data and phenotyping platforms, and the role of machine learning in modeling genotype-phenotype relationships. This study underscores the value of PAVs as a genomic resource for precision breeding and highlights future directions in expanding pangenomic datasets and developing breeder-friendly tools to facilitate their practical application.

Presence/absence variation (PAV); Barley (Hordeum vulgare); Structural genomic variation; Agronomic trait improvement; Pangenome-based breeding