Silver nitrate induced rooting and flowering<i style=""> in vitro</i> on rare rhoeophytic woody medicinal plant, <i style="">Rotula aquatica</i> Lour.

Abstract

Silver nitrate induced enhanced rooting and flowering <i style="">in vitro </i>was achieved on <i style="">Rotula aquatica </i>L., a rare rhoeophytic woody aromatic medicinal plant. Solid and liquid nature of the medium, and growth regulators significantly influenced <i style="">in vitro </i>rooting and flowering. Half-strength MS liquid medium fortified with 2.69 <img src='/image/spc_char/micro.gif'><i style="">M</i> <img src='/image/spc_char/alpha.gif'>-naphthaleneacetic acid (NAA) was effective among different auxins, which induced a mean of 7.3 roots per shoot. Plantlets acclimatized after auxin alone induced rooting exhibited 80% survival in field conditions. Nevertheless, the established plantlets exhibited 50% loss within 3 months. Addition of 11.7 <img src='/image/spc_char/micro.gif'><i style="">M</i> silver nitrate to half-strength MS liquid medium containing 2.69 <img src='/image/spc_char/micro.gif'><i style="">M</i> NAA increased the number of roots to 16.8 per shoot. Plantlets established after rooting in silver nitrate supplemented medium facilitated 95% survival, and the established plantlets did not exhibit loss even after 3 months. Dipping of the basal end of shoots developed <i style="">in vitro</i> in NAA (2.69 <img src='/image/spc_char/micro.gif'><i style="">M</i>) and silver nitrate (11.7 <img src='/image/spc_char/micro.gif'><i style="">M</i>) solution (made in water) for 25 days induced a mean of 12.4 roots per shoot. These plantlets transferred to small pots facilitated 90% survival. Half-strength MS liquid medium containing 2.69 <img src='/image/spc_char/micro.gif'><i style="">M</i> NAA and 11.7 <img src='/image/spc_char/micro.gif'><i style="">M</i> silver nitrate induced flowering earlier. The flowers were morphologically and structurally similar to that on plants growing in field conditions.