MORPHOLOGICAL AND GENETIC DIVERSITY ANALYSIS IN CALENDULA (CALENDULA OFFICINALIS L.) INFLUENCED BY MUTAGENIC EFFECT OF COLCHICINE

Abstract

Calendula officinalis L. (pot marigold) is one of the main aromatic and medicinal plants with many uses in food and medicines. This study was carried out to demonstrate the efficiency of six colchicine concentrations (0.025, 0.05, 0.1, 0.2, 0.4 and 0.8 per cent, w/v) for Calendula improvement and induction of genetic variation. Colchicine treatments had a positive effect on the number of branches/plant, number of inflorescences, fresh and dry weight of inflorescences, inflorescence diameter, total soluble carbohydrates and β-carotene except for plant height, while seed germination and plant height were reduced. Estimation of heritability, genetic advance, genetic variability and selection of superior genotypes will be an important object in crop breeding and genetic improvement programs, and selection of genotypes with higher desirable characters. Heritability was high and ranged from 48.64 to 90.81, respectively (inflorescence diameter and plant height, respectively). Molecular markers based on a RAPD-PCR study elucidate the classification of induced Calendula mutants into two clusters. The coefficient of genetic diversity was estimated at 30%.  A combination of morphological and physiological responses with molecular data contained in the various colchicine treatments illustrated the utility of RAPD-PCR as a method for identifying useful mutants and could be used to detect the colchicine effect significantly. Findings recommend the 0.05 per cent colchicine for efficient breeding calendula mutation and genetic improvement.