The present work aims to synthesize zinc oxide (ZnO) nanoparticles via green approaches using leaf extract of Parthenium hysterophorus. UV–vis and FT-IR tests confirmed the existence of biomolecules, active materials, and metal oxides. The X-ray diffraction structural study exposes the ZnO nanoparticles formation with hexagonal phase structures. SEM and TEM analysis reveal surface morphologies of ZnO nanoparticles and most of them are spherical with a size range of 10 nm. ZnO nanoparticles were revealed strong antimicrobial activity against both bacterial and fungal strains. The germination of seeds and vegetative growth of Sesamum indicum has been greatly improved.

Justicia procumbense leaf, stem and root samples were investigated by phytochemical analysis. Leaf and stem showed higher bioactive compounds compared to the root part. The current work comprises, the zinc oxide nanoparticles (ZnO NPs) synthesis using aqueous leaf extract of J. procumbense and to assess its effect on antimicrobial activity. Formed ZnO NPs were characterized by UV-vis, FT-IR, XRD, and SEM analysis. The UV-vis spectrum exhibited the absorption peak at 370 nm. The FT-IR results indicated leaf extract active biomolecules responsible for the formation ZnO NPs and it confirms band at 421 cm^-1 corresponding to a weak Zn-O stretching. XRD result revealed the hexagonal wurtzite structure with the space group P63mc. The SEM image expresses spherical morphology with a range between 5 to 15 nm. Different concentration of synthesized ZnO NPs was tested against different bacterial (Escherichia coli, Staphylococcus aureus, and Pseudomonas auriginosa) and fungal (Aspergillus niger, A. fumigatous and A. flavus) strains by disk diffusion method. 10 mg concentration of ZnO NPs showed the best antimicrobial effect on all tested bacterial and fungal strains. The potential antimicrobial agents of ZnO NPs can be used for biomedical and pharmaceutical applications. Whereas, the plant leaf extract can be used for other nanoparticles synthesis.

The genetic studies of individual plants, especially self-pollinated species like chickpea need to be evaluated at the DNA level with the help of molecular markers for identifying genetic variations among the plants. High-quality DNA extraction is a prerequisite for genetic studies. Extraction of intact genomic DNA with high – molecular mass is essential for the study of many molecular biology applications like Polymerase Chain Reaction, endonuclease restriction digestion, southern blot analysis, and also for the construction of a genomic library. Several plant DNA extraction methods are available, even though the DNA isolation methods that give good yield employing both quantity and quality is quite difficult especially for self-pollinated crops like a chickpea. This work was focused on developing a standard protocol for the extraction of genomic DNA and identifying different barcoding markers. The result revealed that the CTAB extraction method with slight modification in protocol had been optimized for DNA isolation. The purified DNA, which was isolated through the CTAB method, had excellent spectral qualities and is efficiently digested by a restriction endonuclease, and is found to be more suitable for long-fragment PCR amplification. DNA barcoding is considered as a promising tool because it provides a practical and standard identification of plants. The isolated DNA sample was processed with a classical DNA barcoding approach by amplifying and sequencing with a universal primer. According to the result, among the different barcoding markers studied, the RbcL and Mat K were found to given the best result for molecular species identification in chickpea.

Conventional mutation breeding techniques have often been used to improve yield, disease and pest resistance in crop plants. In the present attempt, two well-known mutagenic agents ethyl methane sulphonate and EMS were employed in order to induce genetic variability variety of chick pea Co -4 obtained from Tamil Nadu Agricultural University. The seeds were treated with different concentrations of EMS (10-50 mM) and Gamma rays (20-60 kR). A total of 369 mutants which alter the height, leaf structure, colour of flower, seed, size of pod, duration of the plant were isolated and characterized. Among them, five true breeding mutants namely Early flowering mutant (EFM), Bold pod mutant (BPM), Bold seed mutant BSM), High yielding mutant (HYM) and High protein content mutant (HPC), which directly influenced the economic value of the crop were selected for further study. The results revealed a significant positive increase in the qualitative traits among the mutant lines. The RAPD profiling of isolated mutants revealed a total of 129 bands, among them 92 were polymorphic with an average of 70.99 percentage of polymorphism. Apart from 28 bands, all the bands seemed to be mutation. The presence of new bands and absence of existing bands might be the reason for quality improvement of chickpea. The RAPD is considered as an excellent marker to differentiate mutants from their parents, to assess genetic variation and phylogenetic relationship.