Figure 1: Vegetative parts of N. khasiana

Methodology

This review was prepared through a comprehensive survey of published scientific literature on Nepenthes khasiana Hook.f. Relevant articles were retrieved from major electronic databases, including Web of Science, Scopus, PubMed, Google Scholar, CrossRef and ResearchGate, using keywords such as “Nepenthes khasiana“, “Indian pitcher plant”, “carnivorous plant”, “genomics”, “transcriptomics”, “phytochemistry”, “conservation”, “tissue culture” and “biotechnology”. Peer-reviewed research articles, review papers and authenticated reports published between 2006 and 2026 were critically examined. Information related to taxonomy, ecology, molecular biology, genomics, metabolomics, phytochemistry, microbial diversity, tissue culture, evolutionary studies and conservation was extracted, compared, and synthesized to provide a comprehensive overview of recent scientific advances (Sahu et al., 2026). Duplicate records and studies lacking scientific validity or sufficient experimental evidence were excluded to ensure the reliability and accuracy of the review.

Results and discussion

Recent scientific investigations have considerably expanded the understanding of Nepenthes khasiana Hook.f., revealing important aspects of its molecular biology, evolution, physiology, ecology, conservation and biotechnological potential (Table 1). Earlier molecular studies employed RAPD and ISSR markers to evaluate genetic diversity among natural populations and demonstrated substantial genetic variation, providing valuable information for conservation and management of this endangered species. Subsequent phylogenetic analyses further suggested that the genus Nepenthes originated on the Indian subcontinent before dispersing to Southeast Asia during the Miocene epoch, highlighting the evolutionary significance of N. khasiana (Table 1). Advances in molecular biology have greatly improved our understanding of the carnivorous adaptations of N. khasiana. Isolation and characterization of chitinase genes confirmed their involvement in prey digestion and plant defense (Table 1).  Transcriptomic studies further demonstrated the expression of numerous digestive enzyme-encoding genes within pitcher tissues and suggested that pitcher evolution resulted from modifications in leaf polarity gene expression (Table 1). More recently, integrated transcriptomic and metabolomic analyses revealed that nutrient availability regulates pitcher formation through coordinated changes in gene expression and metabolic pathways, providing new insights into the developmental mechanisms underlying carnivory (Table 1). Genomic research has reached a significant milestone with the publication of the first complete chloroplast and mitochondrial genomes of N. khasiana. These genomic resources provide an important foundation for future studies on molecular evolution, phylogeny, comparative genomics, genetic improvement and conservation genetics. Such information is expected to facilitate the development of molecular markers and strengthen conservation programs for this threatened species (Table 1). Phytochemical investigations have demonstrated that N. khasiana synthesizes a diverse range of bioactive compounds with important ecological and pharmacological functions. Studies on pitcher fluid chemistry revealed inducible production of antifungal naphthoquinones in response to pathogen attack, indicating an efficient chemical defense mechanism. Recent research further established that naphthoquinones are differentially distributed between reproductive and carnivorous organs, suggesting distinct functional roles in pollination and prey capture.

These findings not only improve the understanding of plant chemical ecology but also highlight the pharmaceutical potential of these secondary metabolites (Tabe 1). Microbial studies have shown that the pitchers of N. khasiana harbour diverse microbial communities, predominantly fungi, which may contribute to nutrient cycling, prey decomposition and maintenance of pitcher health. Investigations on endophytic fungal diversity further revealed numerous fungal taxa associated with healthy plant tissues, indicating their possible roles in plant growth, adaptation, stress tolerance and disease resistance. These studies emphasize that the pitcher ecosystem represents a complex interaction between the host plant and associated microorganisms (Table 1). The application potential of N. khasiana has also expanded significantly in recent years. Plant extracts have successfully been utilized for the green synthesis of stable and biocompatible gold nanoparticles, demonstrating promising biomedical applications while promoting environmentally sustainable nanotechnology. Simultaneously, efficient in vitro propagation protocols have enabled rapid multiplication of healthy plantlets, providing practical tools for ex situ conservation, habitat restoration and commercial cultivation, thereby reducing collection pressure on wild populations (Table 1). Despite these remarkable scientific advances, N. khasiana continues to face serious conservation challenges due to habitat degradation, illegal collection, land-use changes and climate change. Although molecular and biotechnological studies have substantially enhanced current knowledge, long-term ecological monitoring, population genetics, reproductive biology, metabolomic diversity and climate resilience remain insufficiently explored. Future multidisciplinary research integrating genomics, functional biology, conservation ecology and biotechnology will be essential for ensuring the sustainable conservation and utilization of this unique endemic carnivorous plant (Table 1).

Table 1: Scientific advances in N. khasiana

Conclusion and research gaps

Nepenthes khasiana Hook.f., is an ecologically, evolutionarily and pharmacologically important carnivorous plant that represents India’s only indigenous species of the genus Nepenthes. Over the past two decades, substantial scientific progress has enhanced our understanding of its genetic diversity, evolutionary history, pitcher development, digestive physiology, phytochemistry, microbial associations and biotechnological applications. Advances in genomics, transcriptomics, metabolomics, tissue culture and nanobiotechnology have established N. khasiana as a valuable model for studying plant adaptation to nutrient-deficient environments and have provided important tools for its conservation. The availability of complete organellar genome sequences and efficient in vitro propagation techniques has further strengthened the prospects for molecular breeding, conservation genetics and sustainable utilization of this endangered species. Despite these significant achievements, several research gaps remain. Most investigations have been conducted under controlled laboratory conditions, whereas long-term ecological and population-based studies in natural habitats are limited.

Comprehensive analyses of reproductive biology, pollination ecology, seed biology and climate change resilience are still lacking. Functional validation of genes associated with carnivory, nutrient acquisition, stress tolerance and secondary metabolite biosynthesis requires advanced molecular approaches such as genome editing and functional genomics. In addition, the interactions among pitcher-associated microorganisms, plant metabolism and prey digestion remain insufficiently understood. The pharmacological potential of bioactive compounds identified from N. khasiana also requires further in vivo studies, toxicity evaluations, and clinical validation before therapeutic applications can be realized. Future research should adopt multidisciplinary approaches integrating genomics, metabolomics, microbiome analysis, conservation biology and biotechnology to address these knowledge gaps. Strengthening both in situ and ex situ conservation programs, coupled with habitat restoration, population monitoring and community participation, will be essential for safeguarding this unique endemic species. Continued scientific exploration will not only contribute to the conservation of N. khasiana but also unlock its potential in plant biology, biotechnology and pharmaceutical research, ensuring that this remarkable carnivorous plant remains an invaluable component of India’s botanical heritage.

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