“What plant breeding may and may not look like in 2050?”

 

  Providing nutritious and environmentally sustainable food to all people at all times is one of the greatest challenges our society is currently facing. The world population is projected to reach 8.6 billion in 2030, and to increase further to 9.8 billion by 2050. Climate change is a certainty with food systems shifting from maximizing farm production to reducing environmental impact. Many disciplines, along with plant breeding, would need to come together to achieve the goal. An equation that helps define and monitor the progression toward this common goal is the breeder’s equation. Plant breeding may raise or reduce genetic gains based on the breeder’s equation. However, “Accuracy of Selection,” which is a main component of the Breeder’s equation, has been significantly improved by accurate field experiments, laboratory implements, statistical models, and integrating DNA markers into selection. Pre-breeding is another milestone in plant breeding and has contributed to the increase of useful “Genetic Variance.” Shortening “Recycling Time” in breeding has seen great progression, to the point that achieving a denominator equal to one is becoming a possibility. Maintaining high “Selection Intensity” remains the biggest challenge, since adding any technology results in a higher cost per progeny, despite the steady reduction in cost per data point. Furthermore, the concepts of variety and seed enterprise might change with the advent of cheaper genomic tools to monitor their use and the promotion of participatory or citizen science.¹

In an effort to achieve higher genetic gain, Das et al., 2021, conducted a study where genomic selection (GS) and phenotypic selection (PS) were applied on two tropical maize multi-parent synthetic populations to improve grain yield simultaneously under drought and water logging conditions using genomic-estimated breeding values and by exposing them to managed drought and waterlogging, respectively. They reported that realized genetic gains from GS were relatively higher under drought conditions compared to waterlogging for both populations. However, under water logging stress, PS showed at par or better realized genetic gains than GS.³

Rapid generation turnover is another revolutionary approach to realize genetic gains, and in this line, an experiment designed and demonstrated a synergized breeding strategy (SBS) that combined speed breeding, speed vernalization, phenotypic selection, and marker-assisted backcrossing in wheat. This approach was able to achieve a 53% reduction in the time required to develop a BC2 near isogenic line (NIL) with a higher recurrent genome recovery of 91.5% compared to traditional field conditions.² At the turn of the last decade, many geneticists envisioned future plant breeding and which of those visions became reality or not, and which ones may become so in the years to come is a topic of discussion now. Overall, to meet the expectations of the coming decades, plant breeders of tomorrow will necessarily need to design strategic pipelines, allocate resources effectively, and handle all logistics, ensuring the right balance of high selection intensity along with the possibility to raise selection accuracy.

References

1. BASSI, F.M., SANCHEZ‐GARCIA, M. AND ORTIZ, R., 2024. What plant breeding may (and may not) look like in 2050?. Plant Genome, 17(1):20368.

2. CHA, J.K., PARK, H., KWON, Y., LEE, S.M., JANG, S.G., KWON, S.W. AND LEE, J.H., 2024. Synergizing breeding strategies via combining speed breeding, phenotypic selection, and marker-assisted backcrossing for the introgression of Glu-B1i in wheat. Front. Plant Sci., 15:1402709.

3. DAS, R.R., VINAYAN, M.T., SEETHARAM, K., PATEL, M., PHAGNA, R.K., SINGH, S.B., SHAHI, J.P., SARMA, A., BARUA, N.S., BABU, R. AND ZAIDI, P.H., 2021. Genetic gains with genomic versus phenotypic selection for drought and waterlogging tolerance in tropical maize (Zea mays L.). Crop J., 9(6):1438-1448.

4. VAN DIJK, M., MORLEY, T., RAU, M.L. AND SAGHAI, Y., 2021. A meta-analysis of projected global food demand and population at risk of hunger for the period 2010–2050. Nat. Food, 2(7):494-501.