Forest health monitoring remains dominated by occasionally visual surveys and remote sensing products like drones and satellites. These traditional methods of analysis detect stress only after an irreversible physiological damage has occurred. This review regarding in situ tree health critically examines how nanobiotechnology can enable a paradigm shift from symptom-based assessment to continuous, in situ diagnosis of tree health at the individual tree scale. This review defines in situ tree biosensing as the direct interrogation of biochemical and physiological signals of the plant parts like trunk, leaf surface, xylem, phloem and root zone, and systematically classify the biological and physicochemical targets most relevant for early stress detection, including presence of pathogenic DNA/RNA, secreted virulence enzymes, defense related metabolites secreted by plant, reactive oxygen species, phytohormones, osmolytes, ion imbalances, sap conductivity, and embolism related hydraulic signals. Further, it includes analysis of the functional role of nanomaterials in signal transduction, bio-interface and analyte capture for tree biosensing. This highlights how nanostructured electrodes, plasmonic architectures and nanoporous scaffolds enable ultralow volume sampling and high sensitivity detection in complex plant health related parameters. Recent electrochemical, optical, and implantable sensor architectures developed for woody plants are reviewed, with emphasis on microneedle platforms, organic electrochemical transistors, xylem integrated ion sensors, and trunk mounted physiological probes. Beyond analytical performance, this review exposes dominant bottlenecks like sample access, matrix effects, biofouling, and long-term signal drift. This prevents translation from laboratory demonstrations to forest deployable systems. Finally, this review proposes a system level roadmap integrating reliable bio interfaces, low power electronics, edge computing and wireless communication. This connects the in situ nano biosensors with landscape scale forest monitoring infrastructures by linking molecular level stress diagnostics with scalable field deployment. Integration of nanobiotechnology for in situ tree health monitoring offers a realistic pathway toward real time, predictive forest health surveillance.
Mexican butterworts (Pinguicula spp.) are highly valued for their unique biological traits and ornamental appeal, yet many endemic species face threats from habitat loss and poaching. This study proposes micropropagation protocols via direct organogenesis for Pinguicula heterophylla and Pinguicula ibarrae. A comparative evaluation was conducted on the primary and interactive effects of three aromatic cytokinins (6-benzylaminopurine (BAP), kinetin (K), and meta-Topolin (mT)), their concentrations (4.44 or 8.88 µM) supplemented with a basal 1.34 µM 1-Naphthaleneacetic acid (NAA), and two LED lighting conditions: cool white versus red and blue (RB). The analysis demonstrated that shoot proliferation is governed solely by main effects, indicating that optimal cytokinin requirements are stable, genotype-dependent traits that operate independently of light quality. For P. heterophylla, maximum shoot induction (13.7 shoots per explant) was achieved using 4.44 μM K, whereas P. ibarrae exhibited a marked preference for 4.44 μM mT under RB LED lighting, producing 25.5 shoots per explant. Importantly, a significant morphogenic trade-off was identified between multiplication rate and foliar expansion (rosette diameter), illustrating that exogenous plant growth regulators maximize shoot numbers but concurrently restrict individual plantlet size. Additionally, RB LED incubation significantly increased the dry matter percentage in both species and enhanced chlorophyll synthesis in P. heterophylla. Ex vitro acclimatization was successful, achieving a 100
Brassica rapa L. is well known as one of the most recalcitrant Brassica species. A popular, high yielding Bangladeshi Brassica rapa variety, namely Tori-7, is agronomically significant in Bangladesh’s economy and equally unresponsive towards tissue culture practices. The aim of this study was to establish an integrated in vitro regeneration and Agrobacterium- mediated transformation system for Brassica rapa var. Tori-7, addressing the underlying difficulties in its tissue culture processes due to some inherent genotype specific difficulties, with a view to enabling the latest biotechnological tools to be employed in agro-economically significant recalcitrant species. In the current study, supplementing 3.0 mgL−1 BAP, 0.2 mgL−1 NAA and 5.0 mgL−1 AgNO3 with MS media showed the maximum percentage of shooting (cotyledonary leaf with petioles- 42.67
Clematis smilacifolia Wall., a member of the buttercup family (Ranunculaceae), is a less-studied plant species that holds a significant value in the traditional medicine systems and ornamental horticulture. It is a woody climber mainly distributed across tropical and subtropical Asia. To ensure the sustainable utilization and conservation, an efficient in vitro propagation system was developed for the first time for C. smilacifolia. Shoot induction from the nodal explant was achieved on Murashige and Skoog (MS) medium supplemented with various cytokinins. The best shoot induction and subsequent multiple shoot bud formation were obtained on MS medium containing 2.0 mg L−1 thidiazuron (TDZ), with a maximum of 22.86 ± 1.36 number of shoot buds. Shoot elongation was observed only when shoot buds formed by TDZ were transferred to a medium containing 6-benzylaminopurine (BAP). The regenerated shoots were rooted in vitro on half-strength MS medium with 5.0 mg L−1 indole-3-butyric acid (IBA), and subsequently acclimatized under field conditions. To observe developmental changes during acclimatization, a comparative micromorphological study (leaf venation patterns and stomatal characteristics) was also conducted on in vitro-grown and acclimatized plants, revealing that acclimatized plants had better venation patterns and well-developed stomata. The leaf extracts of in vitro-grown and acclimatized plants were also analyzed for phytochemical constituents, total phenolic, flavonoid, and tannin contents (TPC, TFC, TTC), and antioxidant activities (DPPH and ABTS). Methanolic leaf extracts of the in vitro shoots showed significantly higher TPC (7.68 ± 0.03 mg GAE g−1 DW), TFC (11.66 ± 0.50 mg QE g−1 DW), and TTC (111.03 ± 1.41 mg TAE g−1 DW) than the leaf extract of acclimatized plants, i.e., 1.87 ± 0.27 mg GAE g−1 DW, 9.32 ± 0.08 mg QE g−1 DW, and 69.25 ± 1.15 mg TAE g−1 DW, respectively. Further, antioxidant activity in terms of DPPH (IC50 values of 368.56 ± 4.36) and ABTS (IC50 values of 209.76 ± 2.38) radical scavenging activity was also higher in the leaf extract of in vitro-derived plants than that of the leaf extract of an acclimatized plant, i.e., DPPH (IC50 values of 547.7 ± 28.62) and ABTS (IC50 values of 263.36 ± 1.67), respectively. The present investigation demonstrates that the development of a successful in vitro regeneration system could be effectively used for propagation and conservation of C. smilacifolia.
Micrografting combines the advantages of conventional grafting with in vitro techniques, providing uniform, healthy, and phytosanitary propagation material while also enabling the early assessment of compatibility between almond pollinator varieties and rootstocks, a key step for the development and commercialization of new propagation material. To test the principle of virus-free almond plant material, the detection of Prunus necrotic ringspot virus, a major latent pathogen of stone fruit species, was optimized and evaluated by RT-PCR. A first comparative assessment of micrografting devices (parafilm strips, agarose solution drops, tape and double-layer aluminum foil) was carried out to optimize an in vitro micrografting protocol for almond tree, evaluating the suitability of Portuguese pollinator varieties (‘Canhota’, ‘Casa Nova’, ‘Duro Amarelo’) and the classical cultivar ‘Ferraduel’, and testing auxin treatments to improve PNRSV-free propagation, rooting, and acclimatization. Double-layer aluminum foil proved to be the most effective micrografting device, offering superior healing (91.7
