抄録
This study evaluated high-ratio and high-quality propagule production in white Guinea yam (Dioscorea rotundata) using semi-autotrophic hydroponic (SAH). Experiments were conducted to evaluate varietal differences, the effect of single-nodal cutting density in SAH boxes on cutting survival rate and minituber yield, and the direct field transplant of SAH-derived plantlets on seedling survival and minituber production efficiency of yam varieties to optimise the seed tuber system. White Guinea yam seedlings were raised using the SAH technique, and single-nodal cuttings were used as the planting material for the experiments. In Experiment 1, five white Guinea yam varieties exhibited high survival rates (84 – 95%) and produced minitubers in leaf axils, with fresh weights ranging from 0.5 ± 0.1 to 1.3 ± 0.1 g/plantlet. Experiment 2 showed that reducing plant density per SAH box increased minituber weight, yielding 4.2 ± 0.1 g/plantlet in Asiedu and 3.9 ± 0.1 g/plantlet in Kpamyo, respectively. Experiment 3 demonstrated high field survival rates of SAH-derived plantlets (92.5 ± 7.1% for Asiedu and 87.0 ± 8.8% for Favourite), producing a wide range of minituber sizes in the field. Most minitubers (46.6 ± 5.5% for Asiedu and 59.8 ± 6.7% for Favourite) weighed 1 – 5 g, which is ideal for seed tuber production. Our results demonstrate that the SAH method enables cost-effective and scalable high-ratio mass propagation for producing high-quality planting materials (propagules), strengthening seed systems, and accelerating the breeding of white Guinea yam. Hence, we propose a three-stage seed system that leverages vine multiplication for high-ratio propagation, high-quality minituber production from these vines, and seed tuber production using minitubers to optimise seed quality and quantity in white Guinea yam cultivation.
