Effect of Sweet Potato (Ipomea batatas L.) Cutting Length on Growth and Tuber Yield in Ngandanjika, Mpasu Site, Lomami (D.R Congo)

In Ngandanjika (Democratic Republic of Congo), there has been a decline in sweet potato root yields, explained on the one hand by the lack of propagation materials, which are vines, and on the other hand by the old age of these cuttings, which have not undergone any varietal improvement for several years. The average yield there varies from 6 to 14 tons per hectare, whereas in research stations such as Yangambi, yields easily reach 40 tons. With a view to increasing crop yields, the Mbuaya variety, one of the most widely grown varieties, was selected and the effect of the length of the cuttings (vines) on growth and yield during the 2022-2023 growing season was evaluated. The trial was conducted at the MPASU Site on a randomised complete block design with three replicates, each of which was in turn divided into five elementary plots representing the experimental treatments. The treatments consisted of cuttings 20 cm long (T1), 25 cm (T2), 30 cm (T3), 35 cm (T4) and 40 cm (T5). The results show a higher yield (14.7 tons per hectare) of roots with 40 cm long cuttings, followed by 12.7 tons per hectare obtained with 35 cm long cuttings. The lowest average is 4.5 tons per hectare for 20 cm long cuttings.