• In his Final Master’s Thesis (TFM), Seifelden Metwally explores a new breeding paradigm aimed at accelerating crop improvement while safeguarding long-term genetic diversity.

One of the central challenges in plant breeding is balancing genetic gain with the preservation of diversity. How can breeders achieve maximum improvement today without compromising the genetic resources needed for future progress?

This question lies at the heart of the research carried out by Seifelden Metwally, a graduate of the International Master’s in Plant Genetics, Genomics, and Breeding jointly offered by CIHEAM Zaragoza and the University of Lleida. In his TFM, conducted under the supervision of Julio Isidro Sánchez at the Centre for Biotechnology and Plant Genomics (CBPG), Metwally investigated the potential of implementing optimal genomic mating (OGM) strategies within genomic selection programmes.

A PARADIGM SHIFT IN BREEDING

Traditionally, breeders cross the best-performing individuals with each other—an approach known as “elite by elite” mating—to obtain superior progeny. While effective in the short term, repeated use of this strategy gradually reduces genetic variation, limiting long-term improvement.

Graphical abstract illustrating the main three concepts of breeding and the factors balanced in optimal genomic mating (OGM) to guide the selection of parental crosses.

Optimal genomic mating offers an alternative. By combining genome-wide marker information with evolutionary algorithms, OGM identifies mating plans that maximise expected genetic gain while constraining the mating of closely related parents. Rather than selecting individual plants, this framework optimises entire mating strategies with a multi-generational perspective.

The result is a shift in breeding philosophy: from choosing the best individuals to designing the best combinations. This approach aims to speed up the development of high-yielding, resilient crops while maintaining the genetic diversity essential for sustainable breeding.

FINDINGS PUBLISHED IN GENETICS

Metwally’s TFM demonstrated that OGM strategies deliver higher genetic gains than elite-by-elite or random mating, while conserving more genetic variability. These results underline OGM’s capacity to reconcile short-term improvement with long-term breeding goals.

Building on this work, the research led to an original publication in GENETICS titled “MateR: a novel genomic mating framework”, which presents a new methodology for applying genomic mating to better control genetic diversity in breeding programmes.

OPTIMAL GENOMIC MATING APPLIED TO OLIVE BREEDING

Olive breeding in Spain offers a clear example of how optimal genomic mating can support sustainable crop improvement. Spain is the world’s leading olive producer, and breeding efforts increasingly rely on a narrow set of elite varieties valued for their suitability to intensive production systems. Repeatedly using the same parents accelerates the loss of genetic diversity, which is difficult and time-consuming to restore.

Because olive breeding cycles are long—often exceeding a decade—genomic selection is particularly attractive. However, genomic selection can further intensify the use of related elite parents. Integrating optimal genomic mating into these programmes makes it possible to capture the benefits of genomic prediction while actively controlling diversity, helping ensure that today’s gains do not come at the expense of tomorrow’s potential.

ABOUT THE AUTHOR

Seifelden Metwally is a graduate of the International Master’s Programme in Plant Genetics, Genomics, and Breeding organised by CIHEAM Zaragoza and the University of Lleida (2023-2025). He holds a Bachelor’s degree in Biotechnology from Cairo University. He is currently pursuing a PhD in Biotechnology and Genetic Resources of Plants at the Technical University of Madrid and the University of Córdoba.

His research focuses on designing genomic selection programs that accelerate the breeding process without compromising genetic variability in elite breeding populations. He aims to apply the state-of-the-art genomic tools developed at the Rocinante Lab (CBGP) to the olive breeding program in Córdoba, under the supervision of Julio Isidro Sánchez and Concepción Muñoz Díez.

Recently, he represented the Rocinante Lab by presenting their latest work, “A novel framework to control genetic diversity for optimal genomic mating”, at the 19th EUCARPIA Conference on Biometrics in Plant Breeding.