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Significant effect of water stress conditions were observed on morphological and physiological growth parameters of tea (Camellia sinensis). Water stress tolerant tea clones suitable for hilly areas have been identified in this study. The influence of different levels of water deficit on physiological and morphological parameters in tea [Camellia sinensis (L.) O. Kuntze] clones was investigated. Tea clones (BSS-449, BSS-379, P-312, UPASI-9, T-383, RR-17, AV-2 and T-78) growing under controlled condition (under shade, potted condition) were subjected to three irrigation treatment, a control (70.0% soil moisture content), moderate water deficit (38.3% soil moisture content) and sever water deficit (6.9% soil moisture content). Plants submitted to severe water deficit showed significant reduced leaf numbers, leaf areas, and plant heights while reduction in plant height and leaf area and leaf numbers was not significant in moderate water deficit. A significant change in chlorophyll content was observed during the water stress condition. Photosynthesis decreased in both water deficit treatments and was related to stomatal factors and photochemical efficiency of photosystem II. Water relation parameters, e.g. leaf water potential, osmotic potential, turgor potential, relative water content and cellular elasticity were also measured to evaluate plant adaptation to water stress. The highest leaf water potential values were found in the control condition, for all the clones. Cell wall rigidity, measured as elastic modulus, increased under severe water stress, resulting in a loss of turgor at lower leaf water potential. Results of the study suggest that the degree of drought tolerance depends on the interactions between the tea clones and the levels of water stress. The available data also indicates that UPASI-9 is capable of tolerating water stress, and should be suitable for dry areas.

Aconitum violaceum Jacq. is an important medicinal species used for various health ailments including renal pain, rheumatism and high fever. In the present report, a reproducible in vitro regeneration system for Aconitum violaceum Jacq. has developed from the nodal segment of the plant. Induction of shoot buds was achieved on basal Murashige and Skoog (MS) medium. The shoots were elongated on MS medium supplemented with 0.5 μM 6-benzylaminopurine (BAP) and 0.1 μM α-napthaleneacetic acid (NAA) and subsequently transferred to rooting medium. In vitro grown microshoots of A. violaceum were encapsulated in the alginate beads. The success rate of their re-growth was found to be approximately 85.43 %. Of the encapsulated microshoots, 39.86 % exhibited formation of multiple shoots following re-growth on plant growth regulator free MS medium. Healthy root formation was observed in all microshoots following 2 weeks of transfer on half-strength MS medium containing 0.1 μM indole-3-acetic acid (IAA) and 1.0 μM α-naphthalene acetic acid (NAA). These plants were subsequently transferred to pots containing a mixture of soil, sand and compost (1:1:1 v/v), and same were then shifted in the greenhouse with 87 % survival rate. The molecular analysis was carried out using 35 random amplified polymorphic DNAs (RAPD) primers and 25 inter simple sequence repeats (ISSR) primers. Cluster analysis of the RAPD and ISSR profile revealed an average similarity coefficient of 0.966 and 0.974, respectively, confirming genetic stability of tissue culture-raised (TR) plants and synthetic seed-derived plants (SR). The phytochemical analysis of tissue culture-raised and synthetic seeds-derived plants showed higher aconitine content than control plant. The propagation protocol developed in this study provides a basis for germplasm conservation and harnessing the medicinally active compounds of A. violaceum.

Genetic stability and phytochemical analysis of in vitro established plants of Picrorhiza kurroa Royle ex Benth, have been carried out. Random amplified polymorphic DNA (RAPD) and inter simple sequence repeats (ISSR) markers were used to assess the genetic fidelity of tissue culture products including three adventitious shoots from three calli and 6 months old tissue culture raised plants growing in green house condition with mother plant. Apparent genetic variation was detected in the five types of plant materials. The percentage of polymorphic bands in the RAPD and ISSR analysis were 16.25 and 14.54 %, respectively. The genetic similarity was calculated on the basis of RAPD and ISSR data among the five types of plant materials and were ranged from 0.5 to 1.0 (mean 0.75) and 0.47 to 1.0 (mean 0.73), respectively. The similarity coefficient by both RAPD and ISSR analysis revealed that differences between tissue culture raised plants and mother plant was not remarkable, but notable differences were observed among three adventitious shoots regenerated from three calli. The phytochemical analysis of tissue culture raised products showed higher secondary metabolite (picrotin and picrotoxinin) content as compare to mother plant. The information gained on genetic stability/variability will be valuable for the large scale propagation and secondary metabolite production of P. kurroa.

The genus Aconitum (consists more than 250 species) is one of the most important clades of highly valued medicinal plants. Aconitum species are very essential in the traditional device of medication and feature excessive business demand in the herbal marketplace. Some of biologically energetic compounds, e.g., aconitine, indaconitine, pseudoacontine, and so on, had been recognized, and new formulations primarily based on those compounds are being produced as rapid rate. This has led to extensive and rather unregulated exploitation of the species in the wild making the genus a threatened group. Conventional breeding and propagation methods have contributed significantly, but these could not meet up with the ever increasing demands of herbal drug industry globally. Biotechnological interventions, therefore, emerge as an alternative approach in terms of higher production and conservation as well. In recent years, several reports have been published on in vitro propagation of various important Aconitum species. However, advanced biotechnological approaches, such as synthetic seed production and hairy root cultures, are still lacking with only a few reports available. The current review presents an updated overview and critical assessment of secondary data concerning the past and recent biotechnological approaches and interventions in genus Aconitum. This review also attempts to provide a detailed account of work explored so far in micropropagation and emphasizes over the areas not attempted yet, which will act as a baseline data as well as valuable information for different stakeholders and researchers working on various aspects of Aconitum biotechnology.

Picrorhiza kurrooa, one of the important plant species among the various medicinal plants, is endemic to Himalaya. As the plant is useful in the treatment of various diseases, e.g., hepatic disorders, gastric troubles, anemia, asthma, etc., illegal collection from the wild is increasing and now this plant is banned for export in any form and listed as ‘endangered’. Ecological studies carried out on this species in last few decades suggested that the availability of this species in its specific habitats is comparatively lower than other associate species. Possible factors responsible for this depletion are increasing demand in the pharmaceutical industries, habitat specificity, heavy exploitation from the wild, unorganized cultivation practices etc. Biotechnology is playing a crucial role to conserve this important plant species. The past 23 years have witnessed a progressive biotechnological advances made in P. kurrooa. People have published various reports on establishments of in vitro culture techniques including micropropagation, synthetic seed production, plant regeneration via callus-mediated shoot organogenesis, adventitious shoot regeneration, genetic transformation through Agrobacterium rhizogenes, secondary metabolite analysis etc. This review attempts to focus on present ecological status and provide a comprehensive account on the tissue culture-mediated biotechnological interventions made in P. kurrooa for improvement and conservation of this medicinally important plant.