ABSTRACT
There is a steady increase in the demand for orange-fleshed sweetpotato (Ipomoea batatas L.) in South-eastern Nigeria. This study was aimed at determining the planting density appropriate for a high production of orange-fleshed sweetpotato (Ipomoea batatas L.). Field experiments were conducted at the National Root Crops Research Institute, Umudike, in 2015 and at the Research farm of Michael Okpara University of Agriculture, Umudike, Umuahia, Abia state, in 2016 to determine the effect of planting density on the growth and yield of orange-fleshed sweetpotato using three planting densities (25,000; 33,333 and 50,000 plants/ha) and two varieties (Tio-joe and Melinda). The trial was conducted as a 2 x 3 factorial laid out in randomized complete block design (RCBD) with six replicates. The results of the experiment indicated a significant effect on vine length from the Tio-joe over Melind variety at both cropping seasons, and the Melinda variety performed better than the Tiojoe variety in number of branches and number of leaves at 8 weeks after planting (WAP) in 2015 and 12 WAP in 2016. Vine length was influenced by the interaction of planting densities and varieties at 8 WAP in 2015. However, planting density and the treatment combination of the planting densities and varieties had no significant influence on vine length in 2016, number of branches, ornumber of leaves in 2015 and 2016. Similarly, vine girth, weed density, and weed dry weight were not significantly influenced by the varieties, planting densities, and the interaction of varieties x planting density in both seasons. Findings from this study showed that the yield and yield components of Tio-joe were higher than those of the Melinda variety in both seasons. These yield components were not influenced by planting densities and interactions. Although, it was observed that the highest yield components were obtained from 50,000 plants/ha in both seasons.