Trichomes of Higher Plants: Homologous Series in Hereditary Variability and Molecular Genetic Mechanisms
- PDF / 937,498 Bytes
- 12 Pages / 612 x 792 pts (letter) Page_size
- 24 Downloads / 233 Views
EWS AND THEORETICAL ARTICLES
Trichomes of Higher Plants: Homologous Series in Hereditary Variability and Molecular Genetic Mechanisms N. A. Shvachkoa, *, T. V. Semileta, and N. G. Tikhonovaa aFederal
Research Center Vavilov All-Russian Institute of Plant Genetic Resources (VIR), St. Petersburg, 190000 Russia *e-mail: [email protected] Received May 8, 2020; revised June 8, 2020; accepted June 17, 2020
Abstract—The diversity of trichomes is extremely large in the plant kingdom: this is the pubescence of leaves and glumes in cereals and fruits and petioles in fruit plants, thorns in rose and cucumber, hairs on Drosera leaves, or cotton fibers. Trichomes vary in shape, size, structure, location, capability to secrete, etc. All trichomes share a common basic function—protecting plants from various biotic and abiotic factors. Artificial selection sometimes works against the development of trichomes. For example, in the selection of fruit trees, preference is given to those with smooth fruits. Among wild species, intraspecific variability on the presence/absence of trichomes was also detected. The aim of this review is to compare the mechanisms of formation of trichomes in different species in order to estimate extension of homologous series in hereditary variability within different taxa. Data on the morphology of trichomes are summarized. Data on genes determining variability are compared, and orthologous genes are revealed. Comparison with data on gene networks involved in the development of trichomes indicates that, despite the common molecular mechanisms of trichome development in all higher plants, mutations of different components of this gene network confer observed variability within different taxa. Keywords: trichomes, monocotyledons, dicotyledons, genes, gene networks DOI: 10.1134/S1022795420110083
INTRODUCTION In the process of evolution, owing to dynamic changes in environmental conditions, various plant species acquire variability in physiological and morphological characteristics, which contributes to a greater plasticity of species, which allows them to adapt to a wide range of environmental changes. One of the important morphological characters, the variability of which is widely represented in different taxa of higher plants, is the presence or absence of trichomes and their structure and functions. The formation of trichomes is a complex process that occurs in the epidermis of vegetative and generative organs, which is divided into several phases: the phase of initiation, the phase of differentiation, and development of trichomes. Traits associated with the presence or absence of pubescence of a particular part of a plant are often used to determine the taxonomic affiliation and to describe varieties during their official registration (https://www.upov.int/test_guidelines/en/list.jsp). The character of pubescence inheritance was well studied in economically significant plant species as early as the beginning of the 20th century [1–5]; linkage with other morphological characters was shown [6, 7]. A
Data Loading...
