Analysis of phenotypic variability for yield and quality traits within a collection of cassava (Manihot esculenta) genotypes. Issue 3 (27th May 2018)

• Record Type: Journal Article
• Authors: Nduwumuremyi, Athanase; Melis, Rob; Shanahan, Paul; Theodore, Asiimwe
• Is Part Of: South African journal of plant and soil. Volume 35:Issue 3(2018)
• Page Start: 199
• Page End: 206
• Publication Date: 2018-05-27
• Subjects: broad-sense heritability -- carotenoid -- genetic advance -- genotypic variance coefficient -- phenotypic variance coefficient -- postharvest physiological deterioration; Plant-soil relationships -- South Africa -- Periodicals; Plant-soil relationships -- Periodicals; Agronomy -- South Africa -- Periodicals; Soil science -- Periodicals; Botany -- Environmental aspects -- Periodicals; 630
• DOI: 10.1080/02571862.2017.1354406
• Languages: English
• ISSNs: 0257-1862

Abstract

Abstract: Genetic diversity is essential for crop improvement and knowledge of the genetic variability within a breeding population facilitates its future exploitation. This study examined the phenotypic and genetic variability for specific cassava key traits in a collection of 30 genotypes at five environments in Rwanda. Seventy-three percent of the variation in dry matter content (DMC) and 98% of the variation in total carotene (TC) content was explained by genotypes. The broad-sense heritability ( H bs ) of TC was high (99.2%) and the predicted genetic advance (GA; %) from selection was 159.7%. The phenotypic variance coefficients for all traits were higher than the genotypic variance coefficients. The highest H bs (%) and GA for carotenoids was an indication that conventional breeding could improve carotenoid content in cassava using simple recurrent selection. The postharvest physiological deterioration (PPD) showed significant ( p < 0.05) negative correlation and interrelation with TC and DMC, indicating that the high-TC and low-DMC cultivars could have delayed PPD. The higher-TC genotypes could be used to improve TC in the cassava population and consequently could contribute to the development of delayed-PPD cultivars. The results confirm that there is useful variation for key traits within the collection that could be indicative of a broad range of useful variability in natural populations, landraces and cultivars that could be exploited for breeding.