Janhvi Mishra Rawat

Influence of plant growth regulators on indirect shoot organogenesis and secondary metabolite production in Aconitum violaceum Jacq.

Influence of plant growth regulators on indirect regeneration and secondary metabolite production in Aconitum violaceum Jacq. was evaluated. Among the different plant growth regulators studied, 2.5 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 0.25 μM kinetin (Kn) promoted the highest frequency of callus production for indirect regeneration. 6-Benzyl aninopurine (BAP) was more effective in improving shoot regeneration and secondary metabolite production compared to thidiazuron (TDZ). The highest frequency of regeneration (61.8%) was obtained when calli were transferred to Murashige and Skoog medium supplemented with 1 μM BAP and 0.5 μM α-naphthalene acetic acid (NAA) and was more than two-times higher when compared to the treatments with cytokinin only. Supplementation with low NAA concentrations resulted reduction in in vitro secondary metabolite production in most cases, when compared to treatments with cytokinin only. Moreover, differences in cytokinin concentrations significantly affected secondary metabolite production in some cases. The current findings highlighted the differential effects of auxin-cytokinin interactions on indirect shoot regeneration and the production of secondary metabolites in A. violaceum . Key words: Cytokinins, auxins, plant tissue culture, indirect regeneration, aconitum violaceum , secondary metabolites.

The Potential Contribution of Wildlife Sanctuary to Forest Conservation: A Case Study from Binsar Wildlife Sanctuary

Forest vegetation of a protected area (Binsar Wildlife Sanctuary) in Kumaun region (west Himalaya) was analysed for structure, composition and representativeness across three different altitudinal belts, lower (1,600–1,800 m a.s.l.), middle (1,900–2,100 m a.s.l.) and upper (2,200–2,400 m a.s.l.) during 2009–2011 using standard phytosociological methods. Four aspects (east, west, north and south) in each altitudinal belt were chosen for sampling to depict maximum representation of vegetation in the sanctuary. Population structure and regeneration behaviour was analysed seasonally for two years to show the establishment and growth of tree species. A total of 147 plant species were recorded from the entire region of which 27 tree species were selected for detailed study. Highest number was recorded at upper (18 species), and lowest at lower altitudinal belt (15 species). The relative proportion of species richness showed higher contribution of tree layer at each altitudinal belt. The population structure, based on the number of individuals, revealed a greater proportion of seedling layer at each altitudinal belt. The relative proportion of seedlings increases significantly along altitudinal belts (p<0.05) while opposite trends were observed in sapling and tree layers. The density of sapling and seedling species varied non-significantly across seasons (p>0.05). The density values decreased in summer and increased during rainy season. As far as the regeneration status is concerned, middle and upper altitudinal belts showed maximum number of species with fair regeneration as compared to lower altitudinal belt. Overall density diameter distribution of tree species showed highest species density and richness in the smallest girth class and decreased in the succeeding girth classes. This study suggests that patterns of regeneration behaviour would determine future structural and compositional changes in the forest communities. It is suggested that the compositional changes vis-à-vis role of ‘New’ and ‘Not regenerating’ species need priority attention while initiating conservation activities in the sanctuary. This study calls for exploring other less explored Wildlife Sanctuaries in the Himalaya and across the world, to achieve overall biodiversity status in these protected areas and thus to justify their role in conserving biodiversity in the region.

Alterations in growth, photosynthetic activity and tissue-water relations of tea clones in response to different soil moisture content

Key messageSignificant 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.AbstractThe 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 biotechnology: recent trends and emerging perspectives

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.