Study of genetic diversity of Aconitum heterophyllum and its root microbiome

Abstract

Maximum 2048 characters: In the present study, Genetic diversity and root microbiome of a medicinally important medicinal plant- Aconitum heterophyllum, commonly known as Atis, was studied. The roots of A. heterophyllum have been documented to possess various pharmacological properties. They are abundant in diterpene alkaloids and contain atisine, a low-toxicity alkaloid. The species medicinal value fuelled extensive harvesting from the wild, leading it to be critically endangered in natural habitats. The population status was evaluated by studying genetic diversity and structure by utilizing the genetic markers. This analysis encompassed 36 accessions from 8 distinct populations located in Himachal Pradesh and Uttarakhand, India. The characterization of the markers (Microsatellites) involved assessing their transferability and employing primers with a 5'-anchor designed repeat motifs. Ten primers were identified through the transferability assessment from related Aconitum species, and another 4 primers were characterized using identified repeat motifs along with a 5’-anchor. Using these 14 primers across the studied populations, 55 alleles were observed in total with 40.18% average polymorphic loci. Molecular variance analysis demonstrated that most of the genetic variation (92%) occurred among populations, with only 8% within populations. Consequently, the species exhibited sparse genetic diversity, accompanied by significant differentiation at genetic level (Fst = 0.490) and restricted gene flow. The findings suggest a potential decline in the species population stemming from this limited genetic diversity, restricted gene flow and high differentiation. The root microbiome of the target species rhizosphere was examined using a 16S rRNA metagenomic approach. By comparing the root microbiomes of wild and cultivated A. heterophyllum, unique microbes were identified. This study reports several beneficial rhizospheric bacteria, known as Plant Growth Promoting Rhizobacteria (PGPR), associated with the wild populations.