Evaluation of the genus <i>Calendula</i> L. diversity for forming collection of varieties with standard characters
Purpose. Evaluation of collection samples of the genus Calendula L. available at the Experimental station of medicinal plants (ESMP) for the levels of display of morphological characters in order to identify the reference varieties and form a collection of standards. Methods. Field, laboratory, mathematical and statistical ones. Results. During 2012-2014 years the collection of the genus Calendula L. was evaluated, that includes 145 samples of 4 species from 18 countries, for the eight morphological characters (plant height, inflorescence number, full inflorescence number, the color of ligulate and tubular florets, number of rows of ligulate florets, inflorescence diameter, disk diameter) and varieties were distributed by the level of manifestation according to current technique for distinctness, uniformity and stability (DUS). Conclusions. Samples of marigold were identified that can be sources of standards or starting material by plant height, inflorescence number, inflorescence full number, color of ligulate and tubular florets, number of rows of ligulate florets, inflorescence diameter, disk diameter and by all degree of their manifestation. For the highest level of manifestation of character complex (inflorescence diameter, disk diameter, the number of rows of ligulate florets, inflorescence full number and their manifestation pattern) ‘Mandarin Twist' variety appeared to be the best.