Understanding the genetic variability, heritability and association pattern for the characters related to reproductive phase of carrots (Daucus carota L.) in tropical region

Abstract: Carrot is a sexully propagating, biennial root crop. Flowering related characters and germination parameters have a significant role on the root quality and productivity in the succeeding generations. Larger genetic variation exists in nature for seed and umbel characters due its out crossing behavior. In order to study, the nature of genetic variability, heritability and the association pattern, 48 open pollinated varieties were evaluated in tropical region of Karnataka, India during 2015 for 27 characters including seed, umbel and germination parameters. Both qualitative and quantitative characters were used for the study. The data was subjected to statistical analysis for genetic variability components such as genotypic coefficient of variation (GCV), phenotypic coefficient of variation (PCV), heritability in broad sense (h²) genetic advance (GA) and Genetic advance as percent mean (GAM) and Pearson’s correlation. Genetic variability and heritability coupled with genetic advance as percent mean (GAM) were high for number of umbellates per umbel, bolting tendency and umbel weight. Many other characters showed low to moderate genetic variability coupled with moderate heritability and GAM. From the correlation coefficient analysis few characters viz., density of flowers in umbels, number of umbellates/ umbel, umbel shape, bolting tendency showed positive association with seed and umbel yield. Seed length and size of spines on the seeds affects the germination % negatively. Since, the present study involves maximum characters and good number of cultivars with wider genetic background; hence, detailed understanding of the genetic variability and association pattern for these characters in the reproductive phase of carrot would provide useful information for breeders as well as seed scientists.