正常情况下的甘薯子房为双心皮、二室,每室胚珠数固定为二个(Juliano,1935)。因此,在正常受精情况下,每一蒴果可结4粒种子。然而,即使在柱头上有大量花粉粒萌发的和交配中,甘薯品种的授粉结实率一般都很低,每一蒴果都结4粒种子亦极为罕见。迄今前人巴经指出了导致结实率低的一些因素,例 Under normal circumstances the sweet potato ovary is double carpel, two rooms, each ovule is fixed to two (Juliano, 1935). Therefore, under normal fertilization conditions, each capsule can bear 4 seeds. However, even with large numbers of pollen grains germinated and mated on the stigma, sweet potato varieties generally have low rates of pollination and seed setting, and it is extremely rare for each capsule to bear 4 seeds. So far, the predecessors pointed out some factors that led to the low rate of seed set