Garlic (Allium sativum L.) is one of the most important bulb crop grown in India. The bulb contains a colorless, odorless and water soluble compound called allicin. It is widely used as a condiment throughout India. Garlic contains enzymes, vitamin B, flavonoids and certain minerals. It is a good source of antioxidants and protein. Commercial varieties of garlic are vegetatively propagated because of sexual sterility. It is the core ingredient of the Mediterranean region and is used very frequently in Asian, African and European cooking. It is broadly classified into two main categories: hard neck and soft neck garlic. The plant is sown in autumn and the ripen crop is harvested in summer. Garlic has been utilized globally for thousands of years both food as well as medicine. It normalizes the cholesterol and reduces the risk of heart disease and arthritis. It provides protection against various types of cancers. Garlic is a wonder remedy for treating fever, coughs, headache, stomach ache, hemorrhoids, asthma and bronchitis, low as well as high blood sugar and snakebites. Thus, garlic is a rich source of bioactive compounds, which meets the basic nutritional needs of an individual in day to day life.

The data presented herein reports a rapid and efficient method for direct plant regeneration at high frequency without intervening callus formation from shoot tip (93%) and nodal segment (60%) cultured on MS media supplemented with 0.5 mg l -1 KIN, 0.25 mg l -1 BAP, 0.1 mg l -1 IAA and 100 mg l -1 CH. Conversely, leaf and internodal explants were poorly responsive. Adventitious shoot buds arose not only from the cut ends but all along the surface of the explants leading to the formation of clusters with multiple shoots. Multiple shoots upon transfer to MS media supplemented with 2.0 mg l -1 IBA induced efficient rooting (80%). In vitro flowering was observed when tissue culture-raised plantlets were maintained for extended period in culture. Shikonin was induced in roots of regenerated plants which often exudates in the culture medium was quantified spectrophotometerically by recording absorbance at 620 nm and estimated to be 0.50 mg g -1 fresh weight of tissue at the end of the 50 days of culture. The regenerated plants were successfully acclimatized, hardened, and transferred to soil in green house for micropropagation. The protocol developed here will be very useful for the supply of Arnebia hispidissima all year as a raw product necessary for obtaining Shikonin for the cosmetic, dyeing, food, and pharmaceutical industries.

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Data presented herein provides a rapid and efficient method for Agrobacterium rhizogenes-mediated genetic transformation of Arnebia hispidissima for hairy root cultures as well as for enhancing Shikonin production. Etiolated explants viz. shoot tip, nodal, leaf and internodal segments were co-cultivated with Agrobacterium rhizogenes for induction of hairy root. Among the various explants employed, leaf explant showed maximum 70.7% response followed by shoot tip 48.3%, nodal segment 38.7% and internodal segment 9.3%. Integration of Ri plasmid rolB gene in the transformed hairy root cultures was confirmed by PCR analysis using forward (FrolB) and reverse (RrolB) primers of rolB gene resulting in the amplification of 0 ~ 0.8 kb fragments. Medium compositions have been optimized for in vitro induction of Shikonin in hairy root cultures of Arnebia hispidissima. Hairy roots on hormonefree MS medium showed red spots in the older part of the tissues which turned white after a second subculture. Whereas hairy roots cultured on RC medium showed faster growth and produced large amount of Shikonin. The Shikonin content in transformed hairy root culture was estimated by recording absorbance at 620 nm and quantified against authentic sample of Shikonin. Shikonin content was estimated to be 0.85 mg g -1 fresh weight of tissue at the end of the 50 days of culture. The results presented herein will help to design strategies for bridging the gap between ever increasing demand and supply of raw products necessary for obtaining Shikonin for cosmetic, dyeing, food, medicinal, and pharmaceutical industries.

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