Molecular characterization of India Ginseng Withania somnifera (L) using ISSR markers.

BACKGROUND: Ashwagandha (Withania somnifera (L.) Dunal), popularly known as Indian ginseng or winter cherry is a multipurpose plant of immense therapeutic value in the ayurvedic and indigenous medicine system and distributed in wide geographic locations and exhibiting extensive phenotypic and chemical variability. METHODS AND RESULTS: The present study was carried out to assess the molecular genetic diversity among 4 CIMAP varieties and five local cultivars of ashwagandha and cluster dendrograms were created by using 20 ISSR primers. A total of 224 bands of varied length were produced, out of which 193 (86.1%) products were polymorphic and 31 (13.8%) products were monomorphic. Where each ISSR arbitrary primer had 5-16 valuable bands with an average of 11.2 bands per primer, of which 86.16% bands were polymorphic. The PIC values ranged from 0.16 to 0.36 with an average PIC value of 0.29 and RP values ranged from 2.22 to 7.99. The UPGMA cluster analysis of 20 ISSR primers grouped the nine accessions into 2 major clusters. The first and second major cluster consists of seven and two accessions respectively. CONCLUSION: Therefore, this study provides evidence that ISSR based molecular diversity assessment can be used as an efficient tool for detecting similarity and phylogenetic relationships among genotypes of Withania somnifera collected from different geographical locations. This information can be used to improve root and other characteristics of ashwagandha genotypes and there is also scope for the development of high-yielding varieties by selecting diverse parents for crossing (based on the molecular diversity) from the present accessions.

Arsenic-induced differential expression of oxidative stress and secondary metabolite content in two genotypes of Andrographis paniculata.

The present study explores the differential responses of two genotypes (APwC: wild collection and APMS: mass selection line) of A. paniculata against the three application rates of arsenic (42, 126, and 200 mg kg-1). The oxidative enzymes, As accumulation in different tissues, plant growth, and content of pharmacologically important ent-labdane-related diterpenes (ent-LRDs) of the two genotypes were evaluated in the study. Results demonstrated that As uptake significantly reduced plant biomass in APwC and APMS by 5-41.5% and 9-33% in a dose-response manner, respectively. The APMS exhibited lower bioconcentration and translocation factors, higher As tolerance index, and higher content of ent-LRDs as compared to APWC. As treatment induced a decrease in the sum of four metabolite content of APMS (1.43 times) and an increase in that of APWC (1.12 times) as compared to control. Likewise, variance in the production of 5,7,2',3'-tetramethoxyflavanone, and stress enzymes was also observed between APwC and APMS. The increase in the expression of ApCPS2 suggested its involvement in channeling of metabolic flux towards the biosynthesis of ent-LRDs under As stress.

Treatments with native Coleus forskohlii endophytes improve fitness and secondary metabolite production of some medicinal and aromatic plants.

Endophytes have been shown to play a crucial role in determining the fitness of host plant during their association, yet the cross-functional effect of endophytes of one plant on another plant remains largely uncharacterized. In this study, we attempt to analyze the effect of native endophytes of Coleus forskohlii (Phialemoniopsis cornearis (SF1), Macrophomina pseudophaseolina (SF2), and Fusarium redolens (RF1), isolated from stem and root parts) on plant growth and secondary metabolite enhancement in medicinal plant Andrographis paniculata, and aromatic plants Pelargonium graveolens and Artemisia pallens. Here, we report, endophytic treatments with SF2 (21%) and RF1 (9%) in A. paniculata resulted in significant enhancement of andrographolide along with plant primary productivity. Correspondingly, application of fungal endophytes RF1, SF1, and SF2 significantly improved the plant growth (11 to 40%), shoot weight (28 to 34%), oil content (44 to 58%), and oil yield (72 to 122%) in P. graveolens. Interestingly, treatment of A. pallens with three fungal endophytes resulted in significant enhancement of plant productivity and oil content (12 to 80%) and oil yield (32 to 139%). Subsequently, the endophyte treatments RF1 and SF1 enhanced davanone (13 to 22%) and ethyl cinnamate (11 to 22%) content. However, SF2 endophyte-treated plants did not show any improvement in ethyl cinnamate content but enhanced the content of davanone (10%), a signature component of davana essential oil. Overall, results depict cross-functional role of native endophytes of C. forskohlii and repurposing of functional endophytes for sustainable cultivation of economically important medicinal and aromatic crops.