Sandalwood (Santalum album L; family Santalaceae) is a highly significant aromatic oil yielding tree. It is valued for two important traits, heartwood and essential oil obtained from the heartwood. This study was proposed to assess the morphological and genetic variability of sandalwood accessions. For this, genotypes were randomly selected (n = 177) from the 14 populations from three states in southern India. The total heartwood oil content and quality was estimated by UV method and GC-MS. Total 14 oil-specific genic SSR markers were procured to evaluate the genetic diversity among the sandalwood accessions. Total core size, heartwood content, and oil of S. album ranged from 4.4 to 19.1 cm; 0.0 to 17.3 cm; and 0.0 to 5.96% with covariance 27.61, 85.25, and 73.12% followed by mean 9.74, 3.77, and 2.71, respectively. Genetic diversity estimates were highly polymorphic in terms of Na 7.28, Ne 5.89, He 8.0 PIC 0.891, with little Ho, and F-0.922. AMOVA revealed that minimal genetic variation among populations and highest variation was found among individuals with Nm (58.4). The UPGMA reveals the cluster favored the grouping pattern by the PCA analysis. Structure and PCA analysis clustered the entire populations into two major groups with F ST 0.046 in which population of Kerala and Karnataka were pure and Telangana accessions were found admixtures. No significant correlation (r 2 = 0.23, P = 0.00) was observed between heartwood oil and genetic structures. A high degree of transferability of genic markers would facilitate the assessment of novel genotypes for future tree improvement and conservation of Sandalwood populations.

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Sandalwood (Santalum album L.) is the second most expensive wood in the world. There are approximately 16 species of sandalwood (S.

Dendrocalamus stocksii is fast cultivating economically important forest crop species. National Mission of Bamboo Application (NMBA) of India has been identified in 15 industrially important bamboo species. Traditionally it was propagated through by offset cuttings and rhizome splitting which was not meeting the demand, culm cuttings needed mass material to propagate and rooting percentage mixed. Plant regeneration through somatic embryogenesis was achieved in callus cultures derived from the callus initiated through type of explants viz. leaf, leaf sheath, shoot tip, nodal shoot segments, and inter node segments from aseptic cultures. Explants were cultured on Murashige & Skoog basal media supplemented with 2,4 Dichloro diphenyle ethane 0.44 µM/L with additives (Ascorbic acid 8.8 µM/L, citric acid 4.8 µM/L Cysteine 3.02 µM/L and Glutamine 14.6 µM/L) with 3% sucrose and Agar agar 0.6%. Cultures were incubated in the dark at 25˚C ± 1˚C. Out of five types of explants nodal shoot induced callus > 80% followed by leaf sheath (60%) and no callus was induced in leaf. Various nutrient media viz. Murashige and Skoog (MS), Woody Plant Media (WP), Gamborg media (B5) and Heller's (HE) media fortified with 2,4 D (0.2-1.10 µM/L) and Kinetin 0.10 µM/L were tested for high frequency callus induction. Among four nutrient media tested MS media fortified with 2,4 D (0.55-1.1 µM/L) 100% callus induction. Calli multiplication was carried out with various concentrations of PGR's with 10% coconut milk. Out of these MS media 2,4 D 0.55 µM /L and 10% coconut milk concentration were found best for high frequency (80%) calli multiplication. Various combinations of α-naphthalene acetic acid (NAA) with N 6-benzyiaminopurine (BAP) and kinetin were tested for embryo germination, out of which MS media supplemented with NAA 0.55 µM /L and BAP 0.22 µM /L were showed high frequency (80%) germination. Germinated plantlets carefully transferred to polybags containing potting mixture of sand How to cite this paper: Somashekar, P.V.,