Genetic and genomic resources of Santalum album: past achievements and future prospects.

Abstract

Santalum album L. (Sandalwood) is a commercially and medicinally significant tree species native to India and is widely distributed across Asia and Australia. Valued for its high-quality heartwood and essential oil, sandalwood plays a vital role in the pharmaceutical, cosmetic, and cultural industries. India contributes to more than 85% of global production, but natural populations have sharply declined due to overexploitation, habitat loss, and disease pressures. Recent genomic advancements, including chromosome-level genome assembly, transcriptomics, and proteomics, have provided critical insights into oil biosynthesis, heartwood formation, and stress response mechanisms. Studies have identified key transcription factors, such as MYB and WRKY; gene families, such as TPS and SAUR; and enzymes involved in secondary metabolism and abiotic stress tolerance. Molecular markers such as SSRs and SNPs have enabled the assessment of genetic diversity and structure across native and introduced populations, informing conservation and breeding programs. Functional genomic studies have also highlighted the importance of genotype-specific expression profiles for enhancing oil yield and climate resilience. Despite these advancements, key research gaps persist, including limited application of genomic tools in breeding, lack of functional gene validation, lack of CRISPR-based gene editing, and scanty early biomarkers. However, integrated silvicultural-genomic strategies, structured germplasm conservation, and supportive policies are crucial for enhancing productivity, resilience, and sustainable sandalwood cultivation. Therefore, the future research should focus on genome-assisted selection, CRISPR-based gene editing, and the development of functional markers for trait prediction. This review emphasizes the importance of multidisciplinary research in securing the long-term ecological and economic viability of S. album, addressing both production gaps and conservation challenges in the face of global climate change.