Progress and prospects of parasitic plant biodiversity genomics

Parasitic plants have evolved independently at least a dozen times across angiosperms, yielding some of the most extreme examples of genomic reconfiguration in plants. Comparative analyses of plastid, mitochondrial, and nuclear genomes reveal striking convergence across lineages such as progressive plastid genome reduction with retention of a minimal core gene set, alongside lineage-specific divergences, including unusual mitochondrial genome architectures, rampant horizontal gene transfer, and repeated loss of nuclear gene families. Expanded sampling largely confirms stepwise plastid genome condensation but also uncovers rare losses of presumed essential genes, novel tRNA retention patterns, and extremes in genome size and base composition. Mitochondrial genome sizes largely vary (<60 kb to ~4 Mb), shaped by repeat proliferation, recombination, and massive acquisition of foreign DNA. Nuclear genomes integrate these organellar changes with structural and regulatory innovations via e.g. polyploidy and repeat-driven evolution, as well as large-scale gene losses. These insights are increasingly translatable to agriculture through predictive weed management and resistance breeding pipelines that combine preattachment control, postattachment defense, and molecular surveillance to slow virulence evolution. The same genomic toolkits, including high-quality assemblies, organelle haplotyping, and quantitative diagnostics, can support the conservation of nonweedy parasites by refining species boundaries, identifying evolutionarily significant units, and informing International Union for Conservation of Nature (IUCN) Red List assessments and recovery plans. By bridging fundamental and applied research, parasitic plant genomics is poised to move beyond descriptive cataloguing toward design-based strategies that safeguard crop production while conserving some of the most specialized and ecologically vulnerable plants on earth.