High frequency in vitro propagation of Trichopus zeylanicus subsp. travancoricus using branch–petiole explants

Abstract

Trichopus zeylanicus subsp. travancoricus (known as Arogyapacha), an endangered ethnomedicinal plant of the Western Ghats of South India, serves as the major source of the commercial drug Jeevani. The present study established a long-term high frequency in vitro propagation protocol for Arogyapacha. Callus obtained from the branch-petiole explants cultured on Murashige and Skoog (MS) medium with 4.5 lM 2,4-dichlorophenoxyacetic acid upon subculture to medium with different concentrations of 6-benzyladenine (BA) either alone or in combination with an auxin favoured shoot morphogenesis. Medium with 13.3 lM BA alone facilitated high frequency shoot bud (mean of 93.2) formation. Medium with lower concentrations of BA (4.4, 6.6 and 8.8 lM) alone or in combination with lower concentration of a-naphthaleneacetic acid (NAA) or indole-3-butyric acid (IBA) favoured better shoot growth than 13.3 lM BA containing medium, but with reduced number of shoot buds. Subsequent cultures on medium with lower concentrations of BA and also on MS basal media facilitated shoot formation as well as growth of shoots. The shoot regeneration potential showed no decline up to 5 years. Culture of the in vitro-derived whole branch-leaf explants on MS basal medium developed shoots directly from the node. On medium with 19.6 lM IBA, the whole branch-leaf explants induced nodular callus from the node, which developed shoots later. Subsequent cultures on medium with BA exhibited high frequency shoot formation. The transfer of shoots after 10-15 days culture on half-strength MS medium containing 2.7 lM NAA to half-strength basal medium induced a mean of 11.3 roots. Field survival of plantlets relied on the soil mix: a 1:4 ratio of sand and red-soil exhibited the highest plantlets survival (86.6%). RAPD profile of the source plant and plants regenerated from calli after 4 years showed no polymorphism. The established plantlets with morpho-floral features similar to that of the source plants flowered normally and set fruits.

Genomic profile of the plants with pharmaceutical value

“… The genetic relatedness among 51 accessions, 14 species of the genus Zingiber and genetic variability of a clonally propagated species Bua-in and Paisooksantivatana ( 2010 ) Vitex negundo L. Confirmation of the true-to-type nature of randomly selected micropropagated 2-year-old plant Ahmad and Anis ( 2011 ) Swertia chirata Assessment of genetic fidelity of plantlets regenerated through somatic embryogenesis Balaraju et al ( 2011 ) Simmondsia chinensis L. Schneider Sex determination Hosseini et al ( 2011 ) Trigonella foenum - graecum Multilocus genotyping for detection of intraspecific variations Kakani et al ( 2011 ) Bacopa monnieri (L.) Pennell Assessment of genetic diversity in different accessions Karthikeyan et al ( 2011 ) Simmondsia chinensis L. Schneider Assessment of genetic fidelity of micropropagated plants Kumar et al ( 2011 ) Trichopus zeylanicus subsp. travancoricus Assessment of genetic fidelity of in vitro regenerants Martin et al ( 2011 ) Kaempferia galanga L. Molecular profiling of micropropagated plantlets Mohanty et al ( 2011 ) Aloe vera L. Assessment of genetic stability and instability of tissue culture-propagated plantlets Rathore et al ( 2011 ) Terminalia arjuna , T. bellerica and T. chebula Estimation of genetic diversity and evaluation of relatedness Sarwat et al ( 2008 ) Artemisia herba alba …”