Physiological and molecular characterization of in vitro cultures of an endemic medicinal herb, <i>Chlorophytum borivilianum</i>, under abiotic stress

Abstract

This investigation was carried out to evaluate the effects of abiotic stress on the in vitro cultures of Chlorophytum borivilianum. Regenerated plantlets were re-inoculated on media containing different concentrations of sodium chloride (0, 34.2, 68.4, 136.8 and 171.0 μM) and mannitol (0, 10.6, 21.3, 42.7 and 53.4 μM), and thus subjected to in vitro salinity and drought stress. Both salinity and drought conditions affected all the morphological parameters and decreased growth performance at a higher concentration of sodium chloride and mannitol, respectively. The chlorophyll content decreased with time, while proline and protein content increased in the in vitro stress plant. The control and stress tolerant plantlets were subjected to random amplified polymorphic DNA (RAPD) analysis using 24 random decamers primers. Only 15 RAPD primers showed polymorphism and a total of 52 polymorphic loci were scored. The control plants showed the highest similarity with the drought stress plantlet, while plant under salinity stress showed least similarity. Two groups were generated from the RADP data in the dendrogram after UPGMA cluster analysis based on Jaccard’s similarity estimates for the RAPD data. The 2 dimensional scaling by principal component analysis (PCA) was in agreement with the similarity index.

Key words: Abiotic stress, proline, Chlorophytum borivilianum, salinity, mannitol, random amplified polymorphic DNA (RAPD) markers.