FIELD EVALUATION OF SWEET POTATO (Ipomoea batatas L.) VARIETIES FOR YIELD AND YIELD COMPONENTS IN EHA-AMUFU SOUTH EASTERN NIGERIA

Abstract

Sweet potato (Ipomoea batatas L.) is an important root crop that contributes significantly to food security, nutrition, and income generation in Nigeria. However, the productivity of sweet potato in many farming communities remains low due to the continued cultivation of low-yielding local cultivars and inadequate information on the adaptability of improved varieties under specific agro-ecological conditions. This study evaluated the growth, yield, and yield-related characteristics of three improved sweet potato cultivars and one local cultivar to identify suitable varieties for sustainable production in Eha-Amufu, southeastern Nigeria.The experiment was conducted during the 2019 cropping season at the Teaching and Research Farm of the Federal College of Education, Eha-Amufu, Enugu State, Nigeria. Four cultivars (Solo Gold, TIS 087, Mother's Delight, and a local cultivar used as control) were evaluated in a Randomized Complete Block Design (RCBD) with four replications. Data were collected on phenological, growth, yield, and pest-related traits and subjected to analysis of variance (ANOVA). Treatment means were separated using Fisher's Least Significant Difference (LSD) test at 5% probability level, while Pearson correlation analysis was used to determine relationships among traits. Significant (P ≤ 0.05) differences were observed among the cultivars for days to 50% flowering, number of flowers per plant, days to harvest, peduncle length, fresh tuber weight per plot, and fresh tuber yield. Solo Gold flowered earliest (69.50 days), whereas the local cultivar flowered latest (93.25 days). The local cultivar recorded the highest survival rate (81.20%), vine length (20.40 cm), fresh tuber weight per plot (15.80 kg), and fresh tuber yield (266.00 t ha⁻¹). Mother's Delight produced the highest number of tubers per plant (8.36), while TIS 087 recorded the highest number of flowers per plant (18.28) and the lowest pest infestation score (2.00). Correlation analysis revealed significant positive associations between tuber yield and days to 50% flowering (r = 0.60), leaf area (r = 0.53), and days to harvest (r = 0.54). The local cultivar exhibited superior yield performance under the environmental conditions of Eha-Amufu and is therefore recommended for cultivation in the study area. Leaf area, flowering time, and maturity period were identified as important traits associated with yield and may serve as useful selection criteria in sweet potato improvement programmes. Mother's Delight and TIS 087 also possess desirable characteristics that could be exploited in future breeding efforts aimed at improving productivity and pest tolerance.