Genetic Diversity and Molecular Genetics of Ornamental Plant Species

Abstract

ABSTRACTIt is estimated that Plant Kingdom has over half of million species including unicellular organisms, bryophytes, seedless vascular taxa and seed plants on the earth. Among them, approximately the half of the species are flowering plants. Especially, many flowering species of industrial importance belong to Anthophyta (=angiosperms), which contains around 50,000 in monocots and 200,000 species in dicots, respectively. Including the agriculturally important species for food and feed, only about thirty out of thousands of species, are heavily invested for R&D for agricultural and/or industrial uses. Particularly speaking about flower and ornamental plants, there is not much inputs in terms of critical mass and efforts compared with the industrial outcomes and benefits using them. The importance of the plant genetic resources is not only in the number of the available species, but also in the genetic diversity existing in each species, which could provide the precious genetic bases for the flower improvement by breeding and for flexibility in conservation. Only on a small number of such flower and ornamental species, genetic diversity has been estimated at in situ and ex situ collections with a limited number of different traits. Recent development on the molecular markers and specific statistical approaches, especially PCR-based ones with multivariate analyses, are making it possible to assess more preciously the intraspecific and interspecific genetic variation. A progress has been demonstrated even on the species with difficult using of conventional measurements for estimating genetic variation. Consequently, these tools should alleviate pitfalls in conservation and utilization. Genetic variation created with chromosome manipulation such by polyploidy, aneuploidy, cytoplasmic-nuclear substitutions and transposable elements, has been provided unique characteristics in flower breeding. What is more, findings from the plant molecular biology make the flowers further improved with the use of the modern biotechnology. Genetic engineering with the specific alteration of the primary and/or secondary biosynthetic pathways could make more variations in flower appearance, and increase marketable values and the quality and quantity of metabolites for medical and cosmetic uses.