Assessment of the magnitude of genetic diversity among sweetpotato (Ipomoea batatas (L.) Lam) accessions collected from Nigeria and Niger based on agro- morphological and nutritional attributes

Abstract

Most tropical nations regard the sweet potato (Ipomoea batatas (L.) Lam.) to be their most significant staple crop. It is mostly recognized for its ability to withstand drought, grow quickly, and produce with few inputs. A study was carried out during the 2020 and 2021 growing year a field experiment was conducted at the University of Ebonyi State–CAS Campus, to determine variability among sweetpotato accessions, identify traits which are positively and significantly associated with yield and accessions with high yield. A randomized complete block design with three replications was used to compare the performance of improved and local accessions The results of both years and over year combined statistical analysis indicated that the varieties significantly varied in terms of all yield and yield-related traits. As a result, the Umu SPO 3 acquired the greatest values of average root girth in both the 2020 (5.2cm) and 2021 (2.4cm) growing seasons. In both 2020 and 2021 growing seasons and over year combined analysis, the highest average root yield (2.67 Kg), total root yield (8.89 t/ha), were recorded for Koudakou 4 whereas accessions TIS-87/0087 and Dan Maradi had significantly higher mean dry matter content. PCV was found to be higher than GCV suggesting major environmental influence on gene expression controlling those characters. Low heritability coupled with high, moderate and low genetic advance in percent of mean was observed in all characters. Traits considered in the study revealed positive and significant correlations. The two major clusters could be utilized in further breeding programme as newly selected lines to exploit their contrasting traits. The lines could be studied using marker-assisted backcross breeding method or marker-assisted pedigree selection method involving the two lines and the newly selected superior variety, Koudakou-4.