中文摘要：

为探索短蔓西瓜坐瓜较难的原因，对短蔓西瓜和普通二倍体西瓜的花粉生活力和花粉形态结构进行了测定。结果表明，普通二倍体西瓜花粉大小整齐一致，呈短椭球形，极轴和赤道轴比（P/E）为1．34，而短蔓西瓜的空瘪花粉和畸形花粉较多，花粉大小不一，极轴和赤道轴难以区分，比值为1．09；普通西瓜花粉4h萌发率达到了98％，而短蔓西瓜花粉的萌发率只有9％，显著低于普通西瓜。因此推测短蔓西瓜坐瓜难可能与花粉萌发率低和花粉畸形有关。

英文摘要：

In order to find out the reason why fruit setting of short - internode watermelon is difficult, the pollen morphology and viability of short-internode watermelon and normal diploid watermelon were analyzed. The results showed that the pollens of the common diploid watermelon were short ellipsoid shaped with the same size, and the average P/E ratio was 1.34. The pollens of short-internode watermelon varied in size, many anomalous and empty pollens were observed, the polar axis and equatorial axis were difficult to distinguish, the average P/E ratio was 1.09. The 4 h germination rate was significant differences between normal watermelon（98%） and short-internode watermelon（9%） pollens. So the lower fruit setting rate of short-internode watermelon might be caused by anomalous pollens and worse germination rate.