A study was carried out to find out the causes of the low germinability of Songhwan oriental melon (Cucumis melo var, microspermus). Results are summarized as follows:
1. The seeds of Songhwan oriental melon were small (0.96g/100 seeds) and looked more or less chubby as compared to other oriental melon varieties.
2. The variety showed a considerably low germination rate and germination speed of 17% and 3%, respectively at 25 and 30℃, which is the optimum temperature range for germination of melons.
3. Germinability of breeding lines which had Songhwan as a parent tended to drop more seriously as the relationship approaches to Songhwan. Moreover, the germinability of F₁hybrid seeds of which Songhwan was used as female parent showed almost the same germination rate as the original Songhwan while the reciprocal F₁s showed normal germination,
4. When the seed coat was removed, Songhwan oriental melon showed marked increase of germination speed and percentage while other varieties showed low germinability.
5. One-year-old seeds of Songhwan appeared to recover the normal germinability almost completely .
6. Treatments of GA₃, thiourea and KNO₃ seemed to overcome the inhibitory activity on germinability of Songhwan, even though the tendency was not always consistent. In addition, the chemical treatments did not show similar effects on the other oriental varieties and aged seed of Songhwan.
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