苗期溫度、低溫及光週處理對臺灣百合抽莖及開花的影響

The Effect of Seedling Temperature, Prechilling and Photoperiod on the Shoot Emergence and Flowering of Lilium formosanum Wall

臺灣百合實生苗生長發育期可分為三階段：簇生期（rosette phase）、抽莖期（shoot emergence phase）、及生殖生長期（reproductive phase）。實生苗從播種後，連續形成大量簇生葉，著生於地下短縮莖盤上。簇生葉之葉鞘部位肥大成鱗片，遂建立了簇生期。簇生苗短縮莖之莖頂伸長而為地上莖之轉換為感溫型。低溫處（5℃）可有效促進抽莖及花芽形成，苗期溫度20°/15℃可減少對低溫處理之需求。低溫處理效果隨處理期限增加而提高。以處理3~4週最佳，生長於25°/20℃時，抽莖、露蕾、開花三個階段，分別需要4~5週左右，即需12週便可達開花。長日處理對抽莖效果並不穩定，當低溫處理不足時，長日對抽莖具明顯協同促進效果。長日並可促進莖上葉展開速率、節間伸長、提早露蕾及開花。本研究顯示臺灣百合實生苗栽培比其他種百合具早熟性，同時實生苗亦適用於促成栽培而調節花期。

The growth pattern of Taiwan lily (Lilium formosanum Wall.) following sexual propagation could be classified into three developmental stages: rosette, shoot emergence and reproductive phases. After sowing, the seedling produced 40-60 rosette leaves from compressed stem successively. The leaf sheathes transformed into swollen scales, and the rosette phase were established. The transition of compressed stem to elongation was low temperature dependent. Seedling grew at 20°/15℃, but reduced cold requirement for shoot emergence. Prechilling (5℃) could induce shoot emergence efficiently and also shorten the timing for floral bud appearance. The timing of shoot emergence was related to the duration of prechilling. Seedling with 15-20 rosette leves given 15℃ prechilling for 3-4 weeks could be forced to shoot emergence by 4 weeks. Day-length did not affect shoot emergence directly, but could partially substituted the cold requirement. Night break treatment had pronounced effects on the development of post-emergence, enhanced foliage leaf unfolding, inter-node elongation and floral bud appearance. It was suggested that the programming production of Lilium formosanum through sexual propagation was feasible.