In vitro propagation of chia (Salvia hispanica L.) and assessment of genetic fidelity using random amplified polymorphic DNA and intersimple sequence repeat molecular markers

A well-organized micropropagation protocol has been designed for Salvia hispanica L., which bears high nutritional and medicinal value. Seeds of S. hispanica L. were germinated aseptically on half strength MS medium. Nodal explants obtained from in vitro germinated seedling were cultured on MS medium fortified with 6-benzyladenine (BAP) (1–5 mg/l) or Kinetin (Kin) (1–5 mg/l) individually or with α-naphthalene acetic acid (0.1–1 mg/l) and indole3-acetic acid (IAA) (0.1–1 mg/l) for clonal propagation. It was observed that maximum amount of shoots per explant (9.02 ± 2.65) was achieved on culture medium fortified with 3 mg/l BAP which was also optimum for subculturing of the regenerated shoots. Rooting was achieved on medium supplemented with 1 mg/l IBA. The rooted plantlets were acclimatized and transferred to field conditions, with 75% survival rate. Genetic fidelity studies were carried out on regenerated plantlets by 30 random amplified polymorphic DNA and 10 intersimple sequence repeat (ISSR) as molecular markers

Chloroplast ultra structure, photosynthesis and enzyme activities in regenerated plants of Stevia rebaudiana (Bert.) Bertoni as influenced by copper sulphate in the medium.

Stevia rebaudiana (Bert.) Bertoni is an important medicinal plant used as noncaloric commercial sweetener. Plants regenerated with higher levels of copper sulphate in the medium exhibited enhanced activity of peroxidase and polyphenoloxidase (PPO) enzymes. Transmission electron microscopy (TEM) revealed increase in size and number of electron dense inclusions in the chloroplasts of plants regenerated at optimised level of copper sulphate (0.5µM) in the medium. There was decrease in chlorogenic acid (CGA) content. Chl-a-fluorescence transient pattern (OJIP) showed that the photosynthesis process was more efficient at 0.5µM CuSO4 in the medium. 

Novel microbial route to synthesize silver nanoparticles using spore crystal mixture of Bacillus thuringiensis.

Metallic nanoparticles are traditionally synthesized by wet chemical techniques, where the chemicals used are often toxic and flammable. In the present study, the spore crystal mixture of Bacillus thuringiensis was used for the synthesis of silver nanoparticles. Nanoparticles were characterized using UV-Vis absorption spectroscopy, XRD and TEM. X-ray diffraction and TEM analysis showed the average particle size of 15 nm and mixed (cubic and hexagonal) structure. This is for the first time that any bacterial spore crystal mixture was used for the synthesis of nanoparticles. Further, these biologically synthesized nanoparticles were found to be highly toxic against different multi drug resistant human pathogenic bacteria.