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This paper describes an efficient in vitro micropropagation of Artemisia vulgaris using shoot tip and nodal explants. Among the various growth regulators tested, MS medium and B 5 vitamins supplemented with BA (4.44 lM) and KN (2.32 lM) combination was found to yield a better response than BA (4.44-13.32 lM) or KN (0.46-13.92 lM) alone in the medium. BA and KN combinations produced a maximum of 23.3 shoots per explant with 99.8% shooting frequency. Multiple shoots raised were elongated on MS medium containing 0.44 lM BA and 1.44 lM GA 3 . Rooting was highest (98.2%) on MS medium containing 8.56 lM IAA. Rooted plantlets were successfully transferred to plastic cups containing autoclaved garden soil, farmyard soil and sand (2:1:1) for hardening. After 65 days, the plantlets were transferred to Botanical Evaluation Garden and maintained. The survival rate of plantlets varied under acclimatization. Plants looked healthy with no visually detectable phenotypic variations. This is the first report on plant regeneration via organogenesis of A. vulgaris.

An in vitro propagation system for Artemisia vulgaris L., a traditional medicinal plant, has been developed. The best organogenic response, including adventitious shoot number and elongation, was obtained when hypocotyl segments were cultured onto MS medium supplemented with 4.54 lM TDZ (N-phenyl-N¢-(1,2,3-thidiazol-yl) urea). Up to 28 shoots formed per explant for an optimal duration of exposure of 48 days. Regenerated shoots formed roots when subcultured onto a medium containing 8.56 lM IAA (indole-3-acetic acid). Healthy plantlets were transferred to a garden soil:farmyard soil:-sand (2:1:1) mixture for acclimatization, which was successful, and subsequent maturity was achieved under greenhouse conditions over a six-month period. The survival rate of the plantlets varied under acclimatization. The regeneration protocol developed in this study provides a basis for germplasm conservation and for further investigation of medicinally active constituents of A. vulgaris. This optimized protocol has been successfully employed for genetic transformation studies in A. vulgaris, which are currently underway in our laboratory.

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The present study describes a system for efficient plant regeneration via organogenesis and somatic embryogenesis of safflower (Carthamus tinctorius L.) cv. NARI-6 in fungal culture filtrates (FCF)-treated cultures. FCF was prepared by culturing Alternaria carthami fungal mycelia in selection medium for host-specific toxin production. Cotyledon explants cultured on callus induction medium with different levels of FCF (10-50%) produced embryogenic callus. In organogenesis, 42.2% microshoots formed directly from embryogenic callus tissues in plant regeneration medium with 40% FCF. Isolated embryogenic callus cultured on embryo induction medium containing 40% FCF induced 50.2% somatic embryogenesis. Embryo germination percentage was decreased from 64.5 to 28 in embryo maturation medium containing 40% FCF. However, nine plantlets from organogenesis and 24 plantlets from somatic embryogenesis were selected as FCF-tolerant. Alternaria carthami fungal spores (5 9 10 5 spores/ml) sprayed on the leaves of FCF-tolerant plants showed enhanced survival rate over control plants, which plants were more susceptible to fungal attack. The number of leaf spot lesions per leaf was decreased from 3.4 to 0.9 and their lesion length was also reduced from 2.9 to 0.7 mm in organogenic derived FCF-tolerant plants over control. In somatic embryo derived FCF-tolerant plants, the number of lesions was decreased from 3.1 to 0.4 and the lesion size was also reduced to 2.7-0.5 mm when compared to the control. This study also examined antioxidant enzyme activity in FCF-tolerant plants. Catalase (CAT) activity was slightly decreased whereas peroxidase (POD) activity was increased to a maximum of 42% (0.19 lmol min -1 mg -1 protein) from organogenesis and 47% (0.23 lmol min -1 mg -1 protein) from embryogenesis in FCF-tolerant plants. Superoxide dismutase (SOD) activity was also increased to 17% (149 U mg -1 protein) and 19.5% (145 U mg -1 protein) in FCF-tolerant plants derived from organogenesis and somatic embryogenesis when compared with control plants.

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