Diosgenin biosynthesis investigation in medicinal herb (Tribulus terrestris) by transcriptome analysis.

Next-generation sequencing (NGS) has revolutionized the analysis of specific genes, pathways, and their regulation in various species. Tribulus terrestris L., an annual medicinal herb of Zygophyllaceae family, has gained significant attention due to its diverse medicinal properties, including anti-inflammatory, antimicrobial, and anti-cancer effects. Diosgenin, a steroidal saponin, is the major bioactive compound responsible for the medicinal importance of T. terrestris. However, there is a paucity of information regarding the genes involved in the diosgenin biosynthetic pathway in T. terrestris. To address this gap, this study aimed to identify candidate genes associated with diosgenin biosynthesis through whole transcriptome profiling. A total of ∼7.9 GB of data, comprising 482 million reads, was obtained and assembled into 148,871 unigenes. Subsequently, functional annotations were assigned to 50 % of the unigenes using sequence similarity searches against the NCBI non-redundant (NR), Uniprot, KEGG, Pfam, GO, and COG databases, primarily based on Gene Ontology and KEGG-KAAS pathways. The majority of unigenes associated with the biosynthesis of the steroidal diosgenin backbone exhibited up-regulation in the fruit, leaf, and root tissues, except the SQE gene in root. The differential expression of selected genes was further validated through quantitative real-time polymerase chain reaction (qRT-PCR). Additionally, the study identified 21,026 unigenes related to transcription factors and 15,551 unigenes containing simple sequence repeats (SSR). Notably, di-nucleotide SSR motifs exhibited a high repeat frequency. These findings greatly enhance our understanding of the diosgenin biosynthesis pathway and provide a basis for future research in molecular investigation and metabolic engineering, specifically for boosting diosgenin content.

Identification, Characterization and Evaluation of Multifaceted Traits of Plant Growth Promoting Rhizobacteria from Soil for Sustainable Approach to Agriculture.

This study assessed potential of plant growth promoting rhizobacteria (PGPR) found in 34 soil samples collected from Sirmaur, Himachal Pradesh. Out of 238 rhizobacterial isolates, 48 rhizobacterial isolates exhibited multiple PGP (plant growth promoting) traits. Out of the 48 isolates, nine isolates exhibiting most promising PGP traits were evaluated. CSRS12 isolate showed maximum solubilization of phosphate and potassium up to 530.71 and 30.44 mg l-1, respectively. Maximum zinc solubilizing efficiency (ZSE) was also observed in case of isolate CSRS12. The maximum IAA production was observed by isolate PPRS17 with 37.34 mg l-1 followed by PCRS24 with 34.44 mg l-1 after 120 h. Maximum siderophore unit production was observed upto 92.29% by isolate CSRS12 followed by 65.54% with isolate TA1PS. The selected PGPR isolates were identified through 16S rDNA sequencing. The identified PGPRs were Burkholderia arboris (isolate CSRS12), Pseudomonas aeruginosa (isolate PPRS17) and Acinetobacter baumannii (isolate TA1PS). B. arboris CSRS12 isolate showed multiple PGP traits as mineral solubilization of phosphate, potassium and zinc, production of siderophore and ammonia. Among all three PGPR treatment, B. arboris CSRS12 isolate showed significant increment in lateral root number, root and shoot length, fresh and dry weight of root and shoot of mung bean (Vigna radiata) in pot experiments. The results showed that CSRS12 isolate could be used for exploitation as bio-inoculant, which can facilitate better productivity and ecological dynamics for both domesticated crops as well as wild varieties.