Effects of Natural Plant Products as Primers of Nodal Vines on Early Vegetative Growth of Orange Fleshed Sweet Potato (Ipomoea batatas L) Varieties

Aims: The experiment was conducted to determine the effect of priming on early vegetative growth of varieties of orange fleshed sweet potato (OFSP- Ipomoea batatas L.)

Study Design: Treatments were 2 OFSP varieties primed in coconut water, grapefruit juice, mixture of coconut water and grapefruit juice and water (control), in a Completely Randomized Design with 3 replications.

Place and Duration of Study: This study was conducted in the screen house of the Department of Plant Science and Biotechnology, Rivers State University, Rivers State, Port Harcourt Nigeria for a period of 3 months.

Methodology: Nodal vines of 2 varieties of orange fleshed sweet potato UMUSPO 1 “King J”, and UMUSPO 3 “Mothers Delight” were primed in 10% coconut water, 10% grapefruit juice and a mixture of 10% coconut water and 10% grapefruit juice and water (control) for six hours before planting in plastic containers. Time to new sprouting was recorded. Six weeks after planting, number of leaves, nodes, internodes, and vine length were recorded.

Results: Nodal vines of both varieties primed with coconut water and water (control) and those of the variety UMUSPO 3 primed with grapefruit juice initiated sprouts significantly (P =.05) earlier (4 days) than other treatments. Both varieties primed with coconut water and grapefruit juice mixture initiated new sprouts after 7 days. The variety UMUSPO 1 produced higher number of leaves, nodes, and internodes and had longer vines than UMUSPO 3 in all treatments. Priming with mixture of coconut water and grapefruit juice produced a significantly (P = .05) higher number of leaves, nodes, internodes and vine length in UMUSPO 1 than all other treatments.

Conclusion: To double vegetative growth for planting materials, farmers should prime nodal vines of UMUSPO 1 with a mixture of 10% coconut water and 10% grapefruit juice for six hours before planting.