ABSTRACT 

The productivity of sweetpotato (Ipomoea batatas (L.) Lam.] is mainly dependent on the acquisition of genotypes which possess desirable traits and development of high yielding varieties with desired quality attributes. For this purpose, a field experiment was carried out at the National Root Crops Research Institute, Umudike, Nigeria, to characterize and evaluate the level of diversity within and across eight different sweetpotato families (LIGRI X SAUTI, SAUTI X 442162, LIGRI X FAARA, LIGRI X APOMODEN, SAUTI X BOHYE, SAUTI X LIGRI, LIGRI POLY CROSS AND SAUTI POLY CROSS) during the 2015 and 2016 cropping seasons.. A total of 141 sweetpotato genotypes obtained from eight different families of sweetpotato seeds sourced from the West Africa Sweetpotato Breeding Platform, Kumasi, Ghana and two checks were used for this research work.  The sweetpotato families which were poly-cross (half-sib) and controlled cross (full-sib) were characterized morphologically using International Potato Centre (CIP) descriptors. The total of 143 genotypes were laid out in an augmented design. Varied numbers of genotypes recorded significantly higher values than the mean of the checks for days to physiological maturity, fresh weight of storage roots, total storage root yield, marketable storage root yield, dry matter and starch content. However, non significant differences were observed among the genotypes for unmarketable weight. Ligri PC/17 had the highest storage root yield in 2015 cropping season, Sauti X Bohye/8 had the highest storage root yield in 2016 cropping season. For the half-sib families, SAUTI PC and LIGRI PC dry matter ranged from 23.59% to 50.76% while starch content ranged from 13.6400mg100g^-1 to 30.1200mg100g^-1 while for the full-sib families, LIGRI X APOMEDEN, SAUTI X 440163, SAUTI X LIGRI, SAUTI X BOHYE, LIGRI X FAARA, LIGRI X SAUTI dry matter ranged from 18.89% to 51.49% while starch content ranged from 11.21mg100g^-1 to 33.41mg100g^-1. LIGRI X FAARA/8 gave the highest dry matter content of 51.49% while SAUTI X LIGRI/5 gave the lowest 18.89%. LIGRI X FAARA/6 gave the highest starch content of 33.41mg100g^-1 while SAUTI X 440163/5 gave the lowest of 11.21mg100g^-1. Results from the study showed the presence of considerable variation among the genotypes for several traits studied and the possibility of selecting accessions for further testing for different breeding objectives.