Studies on polyploidy induction for improvement of quality traits in ornamental and medicinal plants

Plants provide food, medicine, fuel and they have a positive impact on human life. Ornamental plants have a fundamental role in the human relationship with nature. Medicinal plants as genetic reserves can be considered as the precious national resource for each country and can be the most primary agricultural product. These two groups of plants are part of the natural wealth and have great economic values. Modern breeding methods are invented to resolve the need to diversify ornamental plants. These methods shorten the length of the breeding period to a good extent as well as affecting in the breeding of some plants whose improvement is not possible due to traditional methods. Creating a genetic mutation to improve quality is a necessity in any breeding program. Using natural and induced mutations in improving gene resources is very effective and as a result, helps in the development of improved and new cultivars of ornamental and medicinal plants. Haploid, double haploid and polyploidy plants are the new sources of germplasm that can be introduced as new cultivars or can be used in breeding programs. One of the breeding works to improve the valuable properties of plants is artificial polyploidy induction. Medicinal and ornamental plants with the complete set of duplicated chromosomes (not the usual ones) consist of more distinctive features such as modified phytochemical features, higher content of medicinal molecules, plant shape, plant color, size, scent and long-lasting flowering. To develop a successful protocol for duplicating the chromosomes, some important factors must be considered such as plant genotype and sample type. The type, amount and duration of mitotic inhibitors must also be considered as principal factors. In this article, significant advances in polyploidy are investigated using various mitotic inhibitors in ornamental and medicinal plants.