An efficient micropropagation system via direct shoot organogenesis from hypocotyl segments of Embelia ribes Burm F. was developed. A high frequency (84%) of adventitious shoot induction was obtained on Murashige and Skoog (MS) medium supplemented with additives (283.85 lM ascorbic acid [AA], 118.96 lM citric acid [CA], 142.33 lM cysteine, and 684.22 lM glutamine) and 1.13 lM of thidiazuron (TDZ) after 4 weeks following culture. Further development of shoot primordia into wellgrown shoots of 4-5 cm in length was achieved by subculturing explants along with shoot primordia on MS medium supplemented with 0.44 lM benzyl adenine (BA) and 0.49 lM indole butyric acid (IBA) for three sub-culture periods with an interval of 15 days between them. The highest shoot multiplication was obtained when explants were incubated on MS medium supplemented with 2.2 lM BA and 0.49 lM IBA in 4 weeks. All in vitro developed shoots, 3-4 cm in length, rooted when grown on halfstrength MS basal medium along with 2.47 lM IBA within 4 weeks. Moreover, 100% of shoots developed roots when these were treated with 4.93 lM IBA for 20 min and then transferred to pots containing soilrite mix and grown in the greenhouse. In vitro and ex vitro rooted plants showed a survival of 85 and 95% respectively, during hardening in the greenhouse for a 6-week period.

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Micropropagation of Embelia ribes was achieved through proliferation of axillary shoots obtained from mature plants. Nodal shoot segments, collected MarchMay, exhibited high-frequency (75%) shoot initiation when cultured on Murashige and Skoog (MS) basal medium supplemented with thidiazuron (TDZ) at 1.13 µM and indole-3-butyric acid (IBA) at 0.49 µM. Subculture of sprouted shoots from the original explants on medium containing TDZ (1.13 and 0.45 µM) during the first and second subcultures was found essential for further shoot proliferation, while inhibition of shoot elongation by TDZ could be overcome by transferring shoot cultures onto MS medium containing 6-benzylaminopurine (BAP; 11.10 µM) for the third subculture. Treating the explants with an antioxidant mixture of 568 µM ascorbic acid, 119 µM citric acid, and 307 µM glutathione prior to inoculation, coupled with subculture at 2-wk intervals onto fresh medium, both helped to reduce browning of the explants and facilitated production of five to six shoots/explant. MS medium supplemented with BAP (4.44 µM) and IBA (0.49 µM) induced shoot multiplication, producing five to six shoots/ explant with a shoot length of 3 to 4 cm over a 4-wk culture period. Shoots of 3 to 4 cm in length exhibited 100% rooting within 4 wk after transfer to media containing half the nutrient salt concentration of MS medium with 3.69 µM IBA. Ex vitro rooting in the greenhouse from the in vitro shoots treated with 4.93 µM IBA for 30 min exhibited 95% rooting in soilrite™ medium in a 4-wk period. About 85% of micropropagated plants were established successfully in root trainers. Three-month-old, hardened plants could further be successfully established in the field. In 1 yr, by using the above protocol, 3,200 plants could be produced from a single shoot and 2,700 could be established in the field.

Melia dubia Cav. of family Meliaceae is a fast growing, high value tree species native to India. Isolating DNA from matured dried leaves of M. dubia was difficult due to accumulation of secondary metabolites, majorly polyphenolics, which resulted in dark brown to black colour of the pellet. In this study, a modified STE-(Sucrose, Tris-HCl and Ethylene Diamine Tetra Acetic Acid) CTAB (hexadecyltrimethylammonium bromide) method was standardized for removal of polyphenolics. The protocol developed yielded 200 -1000 ng/µl of quality DNA without any impurities as evident by A260/280 ratio ranging from 1.75 -2.0. It was also suitable for extracting quality DNA from other members of Meliaceae like Azadirachta indica and Melia azedarach. In downstream applications, the extracted DNA was used for PCR amplification by using ISSR and SSR markers. ISSR PCR conditions were optimized in a reaction volume of 25 µl, consisting of 30 ng of template DNA, 1.5 mM MgCl2, 200 µM of each of dNTPs and 2 U of Taq polymerase. The best amplification was observed and the same was applicable for SSR markers.

Summary Clonal Seed Orchard (CSO) of Santalum album L. at Nallal, India consisting of 25 clones originated from different agro-climatic conditions of four southern states (Karnataka, Tamil Nadu, Kerala and Andhra Pradesh) was source of seeds for variability studies. There was vast variation in seed size, weight, germination, vigour and seedling growth of different clones over the years. Seed length, width and weight were positively correlated to each other but seed size had no effect on germination, Germination Value (GV), days taken for germination and early seedling growth. Effects of Clones were dominant and accounted for variation in germination rather than seed size. There was no consistency in the parameters studied in the two years. The impact of these genetic differences in handling of seed lots during bulking, grading and storage for mass propagation of nursery planting stock of S. album is also discussed.