Role of Silver Nitrate on <i>in Vitro</i> Flowering and Shoot Regeneration of <i>Solanum nigrum</i> (L.)—An Important Multipurpose Medicinal Plant

Abstract

Silver nitrate induced MS media enhanced multiple shoot regeneration and in vitro flowering from axillary bud and leaf explants of Solanum nigrum (L.) an important antiulcer medicinal plant. Healthy axillary bud and leaf explants were inoculated on MS medium supplemented with BAP/Kn (1.0 - 2.0 mg/l) in combination with IAA/NAA (0.5 mg/l) and AgNO3 (0.1 - 1.0 mg/l). The explants were responded effectively and good regeneration frequencies were observed in all the combinations of silver nitrate tested when compared to control. Maximum number of multiple shoots (34.3) was found in leaf explants cultured on MS media supplemented with BAP (2.0 mg/l), NAA (0.5 mg/l) and AgNO3 (0.4 mg/l). These regenerated shoots were sub-cultured on to the flowering media. Maximum number of in vitro flowers (12) was obtained from axillary bud explants in BAP (2.0 mg/l), Kn (1.0 mg/l), IAA (0.5 mg/l) and AgNO3 (6.0 mg/l) supplemented media when compared to leaf (4) and control. All the in vitro raised shoots were transferred to rooting medium supplemented with NAA, IBA (1.0 - 2.0 mg/l) and AgNO3 (0.1 - 0.6 mg/l). The best rooting response (24.6) was observed in 2.0 mg/l IBA + 0.4 mg/l AgNO3. The well rooted plantlets were transferred to polybags containing soil + vermiculate in 1:1 ratio for hardening and finally the hardened plantlets were transferred to field conditions.