Agro-Morphological and Cytogenetic Characterization of Colchicine-Induced Tetraploid Plants of Polemonium caeruleum L. (Polemoniaceae)

Abstract

Polemonium caeruleum L. (Polemoniaceae) is a valuable medicinal herb with a wide spectrum of biological activities. Under natural conditions, the productivity of this species is rather low. In this study, colchicine-induced tetraploid plants (2n = 4x = 36) of P. caeruleum were obtained, and for the first time, their morphological and cytogenetic characterization was performed. In the tetraploid plants, raw material productivity and also the content of triterpene saponins were significantly higher than in the control diploids. The analysis of chromosome behavior at meiosis and FISH chromosome mapping of 45S and 5S rDNA generally demonstrated stability of both genomes in the tetraploid plants. Based on chromosome morphology and distribution patterns of the studied molecular cytogenetic markers, all chromosome pairs in karyotypes were identified, and chromosome karyograms and idiograms of P. caeruleum were constructed. The revealed specific microdiagnostic characteristics of P. caeruleum (strongly sinuous cells and anomocytic stomata of the leaf epidermis, and also glandular hairs along the veins) could be useful for raw material identification. In the obtained tetraploids, the predominance of large stomata on the lower leaf epidermis was determined. The studied tetraploids can be used in various breeding programs to obtain high-quality pharmaceutical raw materials of P. caeruleum.

Cytogenetics and Consequences of Polyploidization on Different Biotic-Abiotic Stress Tolerance and the Potential Mechanisms Involved

“…With the increase of ploidy level, the plant height, width and length of flower, flower size, and the number of internodes in dendrobium increased [ 17 , 126 , 127 , 128 ]. Polyploidization affects the floral traits such as flowering time, flower diameter, shape, size, and color, as well as different parts of flowers in kiwifruit and salvia [ 9 , 129 , 130 , 131 , 132 , 133 , 134 , 135 , 136 , 137 ]. These shreds of evidence suggest that polyploidy can be applied in plant breeding by targeting the flower size, shape, color, modifications in size, and the number of floral parts.…”

“…These shreds of evidence suggest that polyploidy can be applied in plant breeding by targeting the flower size, shape, color, modifications in size, and the number of floral parts. Fruit size and fruits number, along with other fruit characteristics such as fruit weight, fruit peel, flesh weight and seed number are affected by the increase of ploidy number [ 130 , 138 , 139 , 140 , 141 , 142 , 143 , 144 ]. Due to variations in cell size and chromosome size ( Figure 5 ), polyploidy changes the characters of the leaf [ 145 , 146 , 147 , 148 , 149 , 150 , 151 , 152 , 153 ].…”