Peculilarities of relationship between traits in collection accessions of Calendula L. genus

Abstract

The aim and tasks of the study. To determin the degree of correlation between morphological and economically valuable traits in genetic diversity collection accessions of Calendula L. genus.

Materials and methods. 145 accessions of four species from 18 countries were investigated. Relationship between quantitative traits was assessed by Pearson pair correlation coefficients; relationship between qualitative traits and others was determined by ranking traits and calculating Spearman rank correlation coefficients.

Results and discussion. Correlations between traits of Calendula L. collection accessions were determined. Relationship between medicinal raw material and seed yields and major quantitative and qualitative traits was assessed.

Conclusions. There was a weak and insignificant positive correlation between the yield of air-dry inflorescences and other traits. The seed yield of calendula accessions was determined by the average seed weight (r = 0.44) and to a lesser degree by maturity of vegetative organs affecting the amount of seeds. No correlation was observed between the flavonoid content, resistance to diseases, pests and drought or any other traits. There was a medium positive correlation between the peduncle thickness and the inflorescence and disc diameters (0.41 and 0.42, respectively), inflorescence doubleness (0.40); correlations between the peduncle thickness and coloration intensity of ray flowers, between the peduncle thickness and the vegetation period length were below the average (0.36); negative correlation (-0.39) was found between the peduncle thickness and the inflorescence number. Extension of the vegetation period increases the inflorescences productivity (through inflorescence number, their diameter and doubleness – r = 0.36 and r = 0.45, respectively) and positively affects their quality via coloration intensity of flowers (0.38).