Polyploidy has the utmost importance in horticulture for the development of new ornamental varieties with desirable morphological traits referring to plant size and vigor, leaf thickness, larger flowers with thicker petals, intense color of leaves and flowers, long lasting flowers, compactness, dwarfness and restored fertility. Polyploidy may occur naturally due to the formation of unreduced gametes or can be artificially induced by doubling the number of chromosomes in somatic cells. Usually, natural polyploid plants are unavailable, so polyploidy is induced synthetically with the help of mitotic inhibitors. Colchicine is a widely used mitotic inhibitor for the induction of polyploidy in plants during their cell division by inhibiting the chromosome segregation. Different plant organs like seeds, apical meristems, flower buds, and roots can be used to induce polyploidy through many application methods such as dipping/soaking, dropping or cotton wool. Flow cytometry and chromosome counting, with an observation of morphological and physiological traits are routine procedures for the determination of ploidy level in plants.

Research on biologically active compounds has been increased in order to improve plant protection against various environmental stresses. Among natural sources, plants are the fundamental material for studying these bioactive compounds as their immune system consists of many peptides, proteins, and hormones. Osmotin is a multifunctional stress-responsive protein belonging to pathogenesis-related 5 (PR-5) defense-related protein family, which is involved in inducing osmo-tolerance in plants. In this scenario, the accumulation of osmotin initiates abiotic and biotic signal transductions. These proteins work as antifungal agents against a broad range of fungal species by increasing plasma membrane permeability and dissipating the membrane potential of infecting fungi. Therefore, overexpression of tobacco osmotin protein in transgenic plants protects them from different stresses by reducing reactive oxygen species (ROS) production, limiting lipid peroxidation, initiating programmed cell death (PCD), and increasing proline content and scavenging enzyme activity. Other than osmotin, its homologous proteins, osmotin-like proteins (OLPs), also have dual function in plant defense against osmotic stress and have strong antifungal activity.

Gladiolus is one of the most important lucrative cut flower crops that is commercially cultivated worldwide due to its various spike forms, size, and shape and color combinations. In order to further increase the commercial and horticultural value by improving the ornamental traits of gladiolus 'White Prosperity', polyploidy was induced by soaking gladiolus corms in different colchicine concentrations (0.1%, 0.2% and 0.3%) for 24 h. Different colchicine concentrations had a little effect on sprouting and survival percentage but it significantly delayed the emergence of sprouts. About one third decreases in plant height along with reduction in number of leaves per plant, leaf area, length and width, chlorophyll content, diameter and number of cormlets per corm was observed in treated plants. Colchicine at 0.1% concentration improved the ornamental value of gladiolus by increasing vase life whereas colchicine at 0.3% was effective in increasing floret diameter. However, the colchicine treated plants exhibited delayed and reduced percentage of flowering corms. Pollen and stomatal study was done for the identification of polyploidy and it showed that both pollen and stomata size were increased while stomatal density and pollen fertility was significantly reduced in polyploid plants. Induction of polyploidy (mixoploids + octoploids) was achieved in all concentrations, however 0.2% and 0.3% concentrations of colchicine were effective for producing large number of polyploid plants. But at 0.1% concentration of colchicine, majority of plants did not show any change in their original ploidy level (tetraploid). These putative polyploids may be helpful for further improvement in ornamental and horticultural value of gladiolus.Ke y wor d s: chromosome, diploid, pollen, stomata, tetraploid

Atherosclerosis may lead to the death of a number of people. In case of atherosclerosis, stiffness of arteries of the heart is caused by the excess deposition of lipids in the coronary arteries. The mentioned condition produces atherosclerotic plaques. When these plaques are burst then clots of blood are formed that cause coronary issues. To overcome this severe disease, extracts of many medicinal plants or spices like garlic, ginger and onion, and many others that are mentioned in this review are used to treat atherosclerosis.

Gladiolus is an important cut flower in the world, and its preference in Pakistan is next to roses. But the main problem that occurs in gladiolus is that it has short vase life. The present experiment was conducted with an objective to investigate the effect of four preservative solutions [distilled water, Sucrose (3%), AgNO3 (250 ppm), AgNO3 (250 ppm) + Sucrose (3%)] and packaging material on postharvest quality of three gladiolus varieties, “Tissue, White Prosperity and Alexandra”. Packaging material consists of control treatment (without packaging), packaging of cut spikes with 100 ppm acetic acid soaked cotton and packaging of polyethylene sheet after sucrose pulsing. The experiment was arranged as two factorial laid out according to completely randomized design (CRD) having three replications. Results showed that preservative solution having combination of AgNO3 (250 ppm) + Sucrose (3%) significantly improves days to open basal floret, floret opening percentage (%), bloom spread (inch), floret length (inch), floret diameter (inch), fresh spike weight (g), dry spike weight (g), fresh weight loss (%) and vase life (days). Moreover, this treatment was also effective in reducing the wilting (%) in all gladiolus varieties. However, for solution uptake (mL/spike) and solution balance (ml/spike), AgNO3 (250 ppm)alone gives the best results. For packaging treatment, the pulsing of a cut spike with 20% sucrose followed by polyethylene sheet wrapping proves to be effective. Among the varieties, Alexandra performed better for all quality parameters in comparison to White Prosperity and Tissue

Radish, one of the important root vegetables, is widely grown in the world due to its easy cultivation, short duration, growing habit, and adaptability to various growing conditions. However, it is still extremely difficult to produce good quality radish roots due to its vulnerability to different preharvest physiological disorders. Important physiological disorders that significantly reduce the yield and quality of radish are forking, pithiness/sponginess, cracking/splitting, hollowness, and internal browning. Different abiotic factors like moisture stress, temperature fluctuation, growing medium, nutrient imbalance, plant density and harvesting time cause a disturbance in the metabolic activities of root tissues that produce non-marketable roots. Therefore, this review provides a detail insight on the causes, physiology of these disorders, and the management practices to prevent them to produce commercial quality roots. This comprehensive knowledge will not only help the growers, but it will provide relative information for researchers as well to control these disorders through breeding innovations and biotechnological tools.

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Tomato (Lycopersicum esculentum L.) is one of the most economically important plants in the Solanaceae family. Water scarcity is one of the major climatic constraints which is affecting all crops including tomato in the world. Selection of water stress tolerant cultivars is an important strategy to overcome this problem. Therefore the present research was conducted to determine the effect PEG induced water stress on germination percentage and early growth stages of tomato seedlings. Fifteen different tomato genotypes were screened under in-vitro conditions using two different concentrations of PEG (2% and 4%). The experiment was arranged in a completely randomized design (CRD) with three replications. Parameters like germination percentage (%), root length (cm), shoot length (cm) and seedling biomass (g) were recorded during the experiment. Results indicated that PEG induced water stress significantly reduced germination percentage (%) and other growth parameters in drought susceptible tomato genotypes (RUS-1, Rustam, R-2017, Pakit, 17904, Kashmiri, Kiara, Avinash, and K.K.2). Whereas in other genotypes “R. Wonder, Naqeeb, Rio grande, T-4, Patfeeder and Nagina” all parameters increase with an increase in PEG concentration. However among these genotypes, “Patfeeder” exhibited highest germination percentage (100 %) with maximum root and shoot length and seedling biomass at highest PEG concentration 4%. Based on experimental results, “Patfeeder” was considered a drought tolerant genotype due to its better performance in different levels of water stress.