将甘薯的近缘野生种Ipomoeatrifida（2x与I．littoralis（4x）杂交，得到三倍体杂种。在三倍体杂种无性系中观察到可被醋酸洋红染色的可育大粒花粉（2n花粉），该花粉频率与花粉母细胞四分体时期的二分体频率呈显著正相关。以三倍体2n花粉系为父本与甘薯杂交，观察到花粉萌发、受精、胚发育和结实，但结实率很低，且种子大多没有生活力。本研究表明，其主要原因有：柱头花粉附着量和花柱中花粉管较少，受精后合子停止发育和胚未能发育成熟。用植物生长调节剂处理对克服子房水平的上述不亲和性有效。 Diploid Ipomoea trifida (2 × cross with I.littoralis (4x) was obtained from the wild relatives of sweet potato, and triploid hybrids were obtained.Explovable pollen grains pollen (2n pollen) stained with acetate magenta was observed in triploid hybrid clones, The pollen frequency was significantly and positively correlated with the diurnal frequency of pollen mother cells in the tetrad stage.The pollen germination, fertilization, embryo development and seed setting were observed by crossing triploid 2n pollen lines with sweet potato, but the seed setting rate Very low, and most of the seeds have no viability.This study showed that the main reasons are: the amount of stigma attachment and the pollen tube in the style less, the development of the zygote stops after fertilization and the embryo fails to mature.Plant growth regulator The above-mentioned incompatibility that overcomes the ovary level is effective.