浙江楠种子休眠生理初探

On the Physiologic Dormancy of Chekiang Phoebe Seed

浙江楠是我国三级珍稀濒危保护树种,其种子具有休眠特性。种胚发育完全,试验表明,除去种皮能很好萌发,离体胚培养时,种胚可迅速萌发,所以它的萌发主要是受到种皮阻碍。种皮中含ABA,通过层积其含量下降,但其种皮水浸提液并不影响已解除休眠及除去种皮的浙江楠种子的萌发。种皮透水性良好,而透气性差。用室温(1.5～11.5℃)或变温(15～25℃,15～30℃)层积21d,均可破除种子休眠。

Phoebe chekiangensis C. B. Shang is a valuable and rare species to be protected in China. The seeds of Chekiang phoebe are of a dormant character. The experiments showed that the seeds could germinate well when the seedcoats were completely removed. All the embryos germinated rapidly in excised embryo tests. Seed germination failure lay in the presence of seedcoat, but not in the dormancy of embryo. Although there were some germination inhibitors in the seedcoats, such as ABA, water extract of the seedcoats could not inhibit the germination of the seeds which had been broken dormancy and removed seedcoats. The seedcoat was good in moisture permeability but was bad in gases permeability. Preferable germination temperature for decoated seeds was 30癈. If the seeds were stratified at room temperature (1.5~11.5CC) or varied temperature (is^C, 8h and 25^ or SOt;, 16 h alternatively) for 21 days, the dormancy would be broken. The effects of any varied temperature treament were better than these of the room temperature treament.