RESUMEN
Aims: To study the effect of iso-osmotic potentials of drought and salinity during seedling growth stage in ricebean. Study Design: Completely randomised design. Place and Duration of Study: The lab experiment was conducted during the year of 2017- 2018 and 2018-2019 in ricebean variety Bidhan 1 at Department of Plant Physiology, Bidhan Chandra Krishi Viswavidyalaya, Kalyani, Nadia, West Bengal, India. Methodology: For studying the effect of iso-osmotic potential of salinity and drought stress, the solutions of NaCl and PEG 6000 with -0.2, -0.4 and -0.8 MPa osmotic potential were used and the experiment was conducted in sand culture using modified Hoagland solution [1] under laboratory condition of diffused light, at around 80±1% relative humidity (R.H.) and at a temperature of 28±1°C. Results: All the biochemical parameters under study, in general were adversely affected by the both stress with the effects being more drastic as the intensity of stress increased. The highest intensity of salinity stress was found to produce more adverse effects than drought in respect of RLWC, leaf chlorophyll as well as protein content in leaves of ricebean in the present experiment. While the content of soluble sugar, starch and phenol in the leaf were more drastically affected by drought stress. Conclusion: The drought stress was found to register more drastic effects on seedling growth as compared to iso-osmotic potential of salinity stress, especially, at the highest intensity of stress in ricebean cultivar Bidhan 1.
RESUMEN
The present study was carried out to determine the possible bioactive components (steroids) of Cenchrus setigerus using GC-MS analysis and in vivo estimation of metabolites (total soluble sugar, soluble protein, proline and total phenolics), photosynthetic pigments (chlorophyll-a, chlorophyll-b and carotenoids) of seedlings and antimicrobial activity of extracts in various polar solvents from the leaves of C. setigerus. Antimicrobial activity was evaluated against three Gram-negative bacteria, including Proteusmirabilis, Klebsiella pneumonia and Agrobacterium tumefaciens andone fungus Aspergillus niger using 'disc diffusion' method, followed by the determination of minimum inhibitory concentrations (MIC) by broth dilution method. Results revealed the presence of some steroids in the isopropyl alcohol extract of C. setigerus:which are (22E)-stigmasta-4,22-dien-3-one(4.93%), δ4-sitosterol-3-one (stigmast-4-en-3-one) (4.31%), fagarsterol (lupeol) (1.25%) and ethyl iso-allocholate (0.32%). Total soluble sugars and chlorophyll-a were also recorded to be highest. The highest activity was exhibited by the isopropyl alcohol and ethyl acetate extract against P. mirabilis.