濕冷層積、刻傷與去殼對鬼櫟（Lithocarpus lepidocarpa Hayata）種子發芽之影響

Effects of Chilling Stratification, Scarification and Excised-embryo on Seed Germination of Lithocarpus lepidocarpus Hayata

從2003年十一月三十日採集之鬼櫟（Lithocarpus lepidocarpus Hayata）果實中取出種子，經水選後，以濕冷層積、刻傷及去殼處理後播種。濕冷層積兩個月可將萌芽率提高至85%，但發芽勢差，需16週才能完成，刻傷後之種子萌芽率雖仍為85%，但發芽勢較強，需8週才達平衡。濕冷層積超過四個月之後，僅濕冷層積者萌芽率下降至20-30%間，刻傷者萌芽率亦下降至50-70%間，發芽勢均增強。濕冷層積4個月及超過4個月之種子去殼後播種，萌芽率在90-100%間，且在播種後一個月內完全萌芽，萌芽集中在播種後2-3週。由此顯示鬼櫟種子具有休眠性，此種休眠性可以4℃兩個月之濕冷層積去除，超過兩個月之濕冷層積會降低萌芽率，但不致造成種子死亡；因長期濕冷層積造成萌芽率的下降，可藉由去殼來改善。因此，濕冷層積後去殼是最有效之種子萌芽促進方法。 Lithocarpus lepidocarpa Hayata seeds were collected in 30, Nov. 2003, and the seed were water selected to remove the hollow seed. After water selected, the seeds were cold stratification under 4 , and showed ℃ after 2 months, 4 months, 6 months, and 8 months. Forty seeds were showed as control, 20 seeds were wounded and 30 seeds were de-shelled. Two months cold stratification increase germination vigor and germination rate (85%) than without cold stratification seed as Liu and Kuo (1999) done, and the germination rate of wounded seeds were the same as the seeds only cold stratification, but could germinated faster. More than 4 months cold stratification, the germination rate of not only control but also wounded seed were decrease, while the germination rate of de-shelled seed were no influenced by the duration of cold stratification and maintained the germination rate in 90-100%. The results show that the seed of Lithocarpus lepidocarpus Hayata has dormancy, which could removed after 4 ℃ cold stratification for two months, and has serious physical barrier for seed germination. The best germination condition of Lithocarpus lepidocarpa will be cold stratification the water selected seed more than 2 months and de-shelled, which the germination rate will more than 90%.