The study was carried out to investigate the chilling requirement and optimum germinating temperature of Diospyros kaki and D. lotus seeds, and to study the effects of alternating temperature, GA and light on the germination of above two species. Interactions between these factors were also studied.
1. In D. lotus, as the stratification periods lengthened up to 10 weeks, the germination percentage increased in all temperature treatments. The best germination was obtained with 30℃ treatment.
2. In all treatments, germination percentage was greater with the alternating temperatures than with constant temperature, and higher percentage was obtained with small differences in alternating temperature under 8hr cycle than with large difference under 16hr.
3. The number of days required for 50% germination (germination rate) was less with higher germination temperature, longer stratification, and alternating temperatures.
4. Seeds of D. lotus germinated better under dark than light. The treatment with 500ppm GA improved germination percentage of seeds which were subjected to cold treatment up to 2 weeks, more effective under light than dark.
5. The promotive effect of shifting on seed germination was observed with the treatments of short stratification periods, and of low germination percentage caused by low germination temperature.
6. Seeds of D. kaki did not require stratification for the germination, but germination rate was greater with longer stratification periods.
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