Genetic Parameters and Prediction of Genotypic Values for Postharvest Physiological Deterioration Tolerance and Root Traits in Cassava using REML/BLUP

The study aimed to estimate the genetic parameters and predict the genotypic values of postharvest physiological deterioration and root characteristics in cassava (Manihot esculentaCrantz) using restricted maximum likelihood (REML) and the best linear unbiased prediction (BLUP). A total of 76 cassava accessions were evaluated over two growing seasons. The evaluated traits included postharvest physiological deterioration response (PPD), root length (RL), root diameter (RD), root weight (RW), dry matter content (DMC), total starch content (TS) and total sugar content (TSU). All the traits had a higher phenotypic variance component than genetic or environmental variance, with genotypic variance making up a larger portion of the total phenotypic variance. Heritability estimates ranged from low to high, with high heritability values being recorded for dry matter content, PPD, and root diameter. The study discovered high genotypic coefficients of variation (CVg) for PPD, root weight and diameter, indicating strong genotypic variability beneficial for selection. As larger genetic effects than non-genetic effects lead to increased selection gains, the highest CVr values for dry matter content and PPD suggest the biggest probability of selection gain. Postharvest Physiological deterioration (PPD) had the highest genetic advance, indicating significant gain in the following generation. Thirty eight genotypes were selected as the most promising based on BLUP index, promoting improvement and genetic gain in several traits. The genotypes selected can be included in cassava breeding programs for PPD tolerance and other tuber traits.