Genetic variability, heritability and variance components of some yield and yield related traits in second backcross population (BC2) of cassava

Abstract

Second backcross population developed from crosses between wild relative Manihot walkarae and Manihot esculenta were evaluated using randomized complete block design at National Root Crops Research Institute (NRCRI) Umudike in 2011 and 2012 cropping seasons. The objective of this study was to assess the extent of genetic variability, heritability, variance components of some yield, yield related traits, pest and diseases from BC2 population. Combined analysis of variance showed significant differences among the genotypes for all the traits evaluated. The phenotypic coefficient of variation (PCV)  in the BC2 population was higher than the corresponding genotypic coefficient of variation (GCV) for all the traits mearsured indicating the effect of environment on the expression of these traits. High heritability was recorded in some of the traits evaluated. This will aid the phenotypic selection for these traits in cassava.   Key words: BC2 population, cassava genotypes, heritability, genetic variability, phenotyic coefficient of variation, genotypic coefficient of variation