Researchers Develop Rice Cultivars Competitive Against Jungle Rice

Strategic Insights -

Investigators at the International Rice Research Institute in Laguna, Philippines, have published a study on developing rice cultivars that are competitive against jungle rice (*Echinochloa colona*). The research, funded by the Bill & Melinda Gates Foundation, aimed to identify genetic markers associated with early seed germination (ESG) and seedling vigor (ESV) in rice. The study utilized 181 early-backcross selective introgression breeding lines (EB-SILs) and identified 3971 common single nucleotide polymorphisms (SNPs) linked to 19 novel quantitative trait loci (QTLs) associated with weed competitiveness.

Key Takeaways:

  • The direct-seeded rice (DSR) system, with its advantages of reduced water usage, less labor requirements, decreased greenhouse gas emissions, and improved adaptation to climate change, is poised to become the dominant rice cultivation method.
  • Weeds, particularly jungle rice (*Echinochloa colona*), significantly hinder DSR and cause substantial yield losses.
  • The research identified 3971 common single nucleotide polymorphisms (SNPs) linked to 19 novel quantitative trait loci (QTLs) associated with weed competitiveness-eight linked to ESG traits and eleven to ESV traits.
  • Key QTLs were located on chromosomes 2, 3, 5, 6, 8, 9, 10, and 12.
  • Candidate genes identified within these QTLs are implicated in the plant's response to various abiotic and biotic stresses.
  • The research enhances the understanding of the genetic basis for ESG and ESV traits critical for weed competitiveness, supporting marker-assisted and genomic selection approaches for breeding improved rice varieties.
  • The study also lays the groundwork for employing gene expression, cloning, and CRISPR editing strategies to combat jungle rice, with potential applications for other weed species.

Statistics:

  • 3971 common single nucleotide polymorphisms (SNPs) linked to 19 novel quantitative trait loci (QTLs) associated with weed competitiveness.
  • 181 early-backcross selective introgression breeding lines (EB-SILs) used in the study.
  • 19 novel quantitative trait loci (QTLs) associated with weed competitiveness.
  • 8 QTLs linked to early seed germination (ESG) traits and 11 QTLs linked to seedling vigor (ESV) traits.
  • Key QTLs located on chromosomes 2, 3, 5, 6, 8, 9, 10, and 12.

Sources:

  • Genome-Wide Dissection of Novel QTLs and Genes Associated with Weed Competitiveness in Early-Backcross Selective Introgression-Breeding Populations of Rice (*Oryza sativa* L.). Biology, 2025,14(4):413. (Biology - http://www.mdpi.com/journal/biology). The publisher for Biology is MDPI AG. A free version of this journal article is available at https://doi-org.sdpl.idm.oclc.org/10.3390/biology14040413.
  • International Rice Research Institute, Rice Breeding Platform, International Rice Research Institute, Los Banos 4031, Laguna, Philippines.