Translation initiation codon (ATG) or SCoT markers-based polymorphism study within and across various Capsicum accessions: insight from their amplification, cross-transferability and genetic diversity

Being an economical and nutritional crop, Capsicum appeases people’s peppery taste and is found to bewidely distributed all over the world having vast diversity. In the present study, genetic polymorphism, cross transferability (CT) and genetic diversity were examined among the 54 different accessions of Capsicum species including 49 of Capsicum annuum, three of C. baccatum and two of C. frutescens, using a set of 36 start codon targeted (SCoT) primers. Of the total, 35 SCoT markers showed successful amplification profile among chilli germplasms and an average primer polymorphism was reported as 81.52% which ranged from 50% (SCoT-6) to 100% (SCoT-11). A total of 365 amplicons were obtained with an average of 10.43 bands per primer and the length of the bands ranged from 150 bp to 1.2 kb. Further, polymorphic information content value of SCoT markers ranged from 0.42 (for SCoT-25) to 0.86 (SCoT-27) with an average of 0.78. The average value of CT of SCoT markers was 44.08% ranged from 14.25% to 57.26% among different chilli accessions. A dendrogram was constructed and established genetic relationship among 54 capsicum species, with the help of translation initiation codon polymorphisms or SCoT primer amplification. This study suggests the effectiveness of SCoT marker system for characterizing and assessing genetic diversity of Capsicum germplasm, which can be used for evolutionary studies and to identify agronomically important traits.

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.