Harnessing genetic diversity for drought tolerance and forage yield improvement in pearl millet germplasms through a pre-breeding framework

Authors: PARRAY, SABREENA - Kansas State University; RAMALINGAM, AJAY - Kansas State University; TUGOO, MIDHAT - Kansas State University; Serba, Desalegn; PRASAD, P.V. VARA - Kansas State University; PERUMAL, RAMASAMY - Kansas State University

Submitted to: Scientific Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/9/2025
Publication Date: 11/14/2025
Citation: Parray, S.A., Ramalingam, A.P., Tugoo, M.Z., Serba, D.D., Prasad, P.V., Perumal, R. 2025. Harnessing genetic diversity for drought tolerance and forage yield improvement in pearl millet germplasms through a pre-breeding framework. Scientific Reports. 15. Article 40033. https://doi.org/10.1038/s41598-025-23884-1.
DOI: https://doi.org/10.1038/s41598-025-23884-1

Interpretive Summary: Pearl millet is recognized for its ability to grow in regions characterized by drought and suboptimal soil fertility. This research was conducted on a diverse set of pearl millet germplasm to identify drought-tolerant accessions suitable for forage parental lines development. A field experiment was conducted under irrigated (control) and rainfed (stress) conditions for two years (2023 and 2024) in Hays, Kansas. Six agronomic traits, namely days to 50% flowering, chlorophyll content, plant height, staygreen, number of productive tillers, and biomass yield were measured. Analysis of the data grouped the germplasm into different maturity groups and drought tolerance characteristics. DNA profiling of thirty top-ranked drought-tolerant germplasms revealed a significant level of genetic variation among the selected germplasms. Traits such as chlorophyll content, staygreen, and biomass yield demonstrated moderate to high heritability for a stable performance across environments and as reliable indicators for drought resilience. Using four crop performance stability models, a total of nine accessions that exhibited broad adaptability to various environments were selected. These results are vital for the development of pearl millet hybrids with enhanced forage yield potential for addressing livestock feed challenges in drought-prone areas.

Technical Abstract: Pearl millet, recognized for its resilience to climate challenges, thrives in drought-prone and poor soil quality areas. This study aims to evaluate the impact of drought stress on six agronomic traits in 188 pearl millet accessions and identify stable and drought-tolerant accessions that can be developed into forage parental lines. Field experiments conducted in summer 2023 and 2024 under irrigated (control) and rainfed (stress) conditions at Hays, Kansas revealed significant differences among the accessions, treatments, and year based on a combined analysis of variance for all the traits evaluated. Rank summation index selected 30 drought-tolerant germplasms per maturity group from the whole collection. Principal component analysis based on Rad-seq SNP data indicated a higher level of genetic variation within the selected and unselected germplasms. By utilizing BLUP-based GGE biplot, MTSI, MGIDI, and FAI-BLUP stability models, we identified three early (E11 - PI197115, E5 - PI197368 and E12 - PI197327), four medium (M19 - PI197465, M5 - PI197436, M1 - PI197326, and M29 - PI197069), and two late (L5 - PI197291 and L19 - PI197278) maturity accessions with broad adaptability across environments. Chlorophyll index, staygreen, and biomass traits served as reliable indicators for drought tolerance, showing moderate to high heritability across maturity groups, and stable performance across years. These results are crucial for developing drought-tolerant parental lines and hybrids with enhanced forage yield addressing livestock feed challenges.