Molecular profiling of fungal assemblages in the healthy and infected roots of Decalepis arayalpathra (J. Joseph & V. Chandras) Venter, an endemic and endangered ethnomedicinal plant from Western Ghats, India

Study on the correlation between soil microbial diversity and ambient environmental factors influencing the safflower distribution in Xinjiang

The effects of soil microbial properties and physiographical factors on safflower distributions in the main safflower plantations of Xinjiang province in China were studied. This study may help determine the basis of the environmental factors for evaluating the geoherbalism of this medicinal plant. The soil microbial biodiversity in the bulk soil and rhizosphere of safflower at different growth stages and from different sampling plots were characterized by analyzing the environmental DNAs in the samples. With general primers targeting the 16S ribosomal DNA for bacteria and the internal transcribed spacer 1 gene for fungi, the study was performed using marker gene amplification coupled with Illumina HiSeq high-throughput sequencing technologies. Correlation analysis and a distance-based redundancy analysis were performed to determine the dominant factors affecting the distribution of the microorganism in safflower soils. A total of 16517 bacterial operational taxonomic units (OTUs) were obtained from all the 108 soil samples of nine safflower sampling plots. At the phylum level, 48 phyla have been identified with Actinobacteria (32.9%) and proteobacteria (28.7%) being predominant. For fungi, 8746 OTUs were obtained, which belonged to seven phyla with Ascomycota overwhelmingly superior in relative abundance. A significant positive correlation was found between soil microbe quantity and ASL (above sea level). Safflower was sensitive to changes in elevation, growing more abundantly in the mountainous regions at heights of around 1,200 m above sea level. It is concluded that the dominant factors affecting the distribution of microorganisms in safflower soils were soil moisture, available N, and ASL.

Character-based DNA barcoding for authentication and conservation of IUCN Red listed threatened species of genus Decalepis (Apocynaceae)

The steno-endemic species of genus Decalepis are highly threatened by destructive wild harvesting. The medicinally important fleshy tuberous roots of Decalepis hamiltonii are traded as substitute, to meet the international market demand of Hemidesmus indicus. In addition, the tuberous roots of all three species of Decalepis possess similar exudates and texture, which challenges the ability of conventional techniques alone to perform accurate species authentication. This study was undertaken to generate DNA barcodes that could be utilized in monitoring and curtailing the illegal trade of these endangered species. The DNA barcode reference library was developed in BOLD database platform for candidate barcodes rbcL, matK, psbA-trnH, ITS and ITS2. The average intra-specific variations (0-0.27%) were less than the distance to nearest neighbour (0.4-11.67%) with matK and ITS. Anchoring the coding region rbcL in multigene tiered approach, the combination rbcL + matK + ITS yielded 100% species resolution, using the least number of loci combinations either with PAUP or BLOG methods to support a character-based approach. Species-specific SNP position (230 bp) in the matK region that is characteristic of D. hamiltonii could be used to design specific assays, enhancing its applicability for direct use in CITES enforcement for distinguishing it from H. indicus.