The genus Nepeta belongs to the largest Lamiaceae family, with 300 species, which are distributed throughout the various regions of Africa, Asia, India, and America. Along with other plant families distinguished by their medicinal and therapeutic values, the Nepeta genus of Lameaceae remains relatively valuable. Hence, the phytochemicals of N. paulsenii Briq. were extracted using different plant parts, i.e., leaves, stem, roots, flowers, and the whole plant by using various solvents (ethanol, water, and ethyl acetate), obtaining 15 fractions. Each extract of dried plant material was analyzed by FT-IR and GC-MS to identify the chemical constituents. The cytotoxicity of each fraction was analyzed by MTT assay and mitochondrial membrane potential and nuclear condensation assays against lung cancer cells. Among the ethyl acetate and ethanolic extracts, the flowers showed the best results, with IC₅₀ values of 51.57 μg/mL and 50.58 μg/mL, respectively. In contrast, among the water extracts of the various plant segments, the stem showed the best results, with an IC₅₀ value of 123.80 μg/mL. 5-flourouracil was used as the standard drug, providing an IC₅₀ value of 83.62 μg/mL. The Hoechst 33342 stain results indicated apoptotic features, i.e., chromatin dissolution and broken down, fragmented, and crescent-shaped nuclei. The ethanolic extracts of the flowers showed more pronounced apoptotic effects on the cells. The mitochondrial membrane potential indicated that rhodamine 123 fluorescence signals suppressed mitochondrial potential due to the treatment with the extracts. Again, the apoptotic index of the ethanolic extract of the flowers remained the highest. Hence it can be concluded that the flower part of N. paulsenii Briq. was found to be the most active against the A459 human lung cancer cell line.

The glucosinolate-myrosinase system is a well-known plant chemical defence system. Two functional myrosinase-encoding genes, THIOGLUCOSIDASE 1 (TGG1) and THIOGLUCOSIDASE 2 (TGG2), express in aerial tissues of Arabidopsis. TGG1 expresses in guard cells (GCs) and is also a highly abundant protein in GCs. Recently, by studying wild type (WT), tgg single, and double mutants, we showed a novel association between the glucosinolate-myrosinase system defence system, and a physical barrier, the cuticle. In the current study, using imaging techniques, we further analysed stomata and ultrastructure of GCs of WT, tgg1, tgg2 single, and tgg1 tgg2 double mutants. The tgg mutants showed distinctive features of GCs. The GCs of tgg1 and tgg1 tgg2 mutants showed vacuoles that had less electron-dense granular material. Both tgg single mutants had bigger stomata complexes. The WT and tgg mutants also showed variations for cell wall, chloroplasts, and starch grains of GCs. Abscisic acid (ABA)-treated stomata showed that the stomatal aperture was reduced in tgg1 single and tgg1 tgg2 double mutants. The data provides a basis to perform comprehensive further studies to find physiological and molecular mechanisms associated with ultrastructure differences in tgg mutants. We speculate that the absence of myrosinase alters the endogenous chemical composition, hence affecting the physical structure of plants and the plants’ physical defence barriers.

The cell wall (CW) as a first line of defense against biotic and abiotic stresses is of primary importance in plant biology. The proteins associated with cell walls play a significant role in determining a plant's sustainability to adverse environmental conditions. In this work, the genes encoding cell wall proteins (CWPs) in Arabidopsis were identified and functionally classified using geneMANIA and GENEVESTIGATOR with published microarrays data. This yielded 1605 genes, out of which 58 genes encoded proline-rich proteins (PRPs) and glycine-rich proteins (GRPs). Here, we have focused on the cellular compartmentalization, biological processes, and molecular functioning of proline-rich CWPs along with their expression at different plant developmental stages. The mined genes were categorized into five classes on the basis of the type of PRPs encoded in the cell wall of A. thaliana. We review the domain structure and function of each class of protein, many with respect to the developmental stages of the plant. We have then used networks, hierarchical clustering and correlations to analyze co-expression, co-localization, genetic and physical interactions and shared protein domains of these PRPs. This has given us further insight into these functionally important CWPs and identified a number of potentially new cell-wall related proteins in A. thaliana.

During 2012–2014 a survey was conducted in different districts of Punjab province, Pakistan and suspected phytoplasma infected plant samples of vegetables, fruits, oilseeds and weeds were collected. Molecular assays were carried out and allowed to detect phytoplasma presence in several of these samples. Nested PCR assays with universal phytoplasma specific primers (P1/P7 and R16F2n/R16R2) indicated phytoplasma presence in symptomatic tomato, Parthenium hysterophorus and onion in Faisalabad province. These are new phytoplasma reports for the geographic area.

‘Candidatus Phytoplasma solani’ alters developmental processes in tomato and cause malformations of both vegetative and reproductive organs. The study was performed to determine the effect of application of phytohormones on “stolbur” strain PO infected tomato and to assess whether application of BTH, an analogue of salicylic acid (SA), jasmonic acid (JA) and ethylen (Et) could protect tomato against the “stolbur” disease development. Expression of SA- and JA-dependent marker genes was also studied in tomato by qRT-PCR. Results indicated that the SA-mediated defence response delay the “stolbur” phytoplasma strain PO multiplication in contrast to the JA and Et-dependent defence pathways.

Using direct and nested PCR technique followed by RFLP analysis, it was found that phytoplasmas were associated with Brassica napus plants showing symptoms such as phyllody, virescence, proliferation, flower sterility, from samples collected during a main survey carried out in different districts of Punjab, Pakistan. The samples from symptomatic plants were collected and observed by electron microscopy and tested using phytoplasma universal primer pairs R16F2n/R16R2, which confirmed the phytoplasma presence. Transmission trials by grafting and also by insects verify that the prokaryotes can be transmitted from diseased to healthy plants.