| 摘要: | 白花海芋(Zantedeschia aethiopica (L.) Spreng.)為天南星科(Araceae)海芋屬(Zantedeschia)多年生球根花卉。本研究利用秋水仙素進行白花海芋 ‘Large White’誘變育種，以增加觀賞性狀多樣性及細菌性軟腐病抗性為育種目標，增加種質資源多樣性。以0.01%、0.05%及0.1%秋水仙素浸泡白花海芋芽基盤試管內24 hr後，培養於芽體誘導培養基誘導芽體形成，接續繼代於發育培養基，獲得54株再生植株。結果顯示0.05%及0.1%秋水仙素處理顯著抑制瓶內再生植株株高，然而出瓶馴化16週後，秋水仙素處理組的植株高度(44.0-49.6 cm)相較於對照組(38.3 cm)具顯著差異。接續調查秋水仙素處理組的植株在觀賞性狀、耐熱性及細菌性軟腐菌抗性表現，以篩選符合本試驗育種目標的變異個體。經三年的性狀調查，篩選出0.1%秋水仙素處理組編號WC09及WC26變異株，其白色佛焰苞尖端帶有綠色，性狀表現穩定。耐熱性調查結果顯示在溫室的高溫(>37C)條件下，唯有0.01%秋水仙素處理組編號WA12與0.1%秋水仙素處理組編號WC15及WC 27的Fv/Fm尚可維持在0.61-0.70，而對照組及其餘秋水仙素處理組植株的PSII最大光化學效能(Fv/Fm)均受嚴重影響，而熱顯像儀結果顯示有數棵單株葉溫散熱性尚佳，平均葉溫34.1-36.6℃。以葉圓片、葉柄切片及根莖小種球切片進行細菌性軟腐菌抗性評估，結果顯示對照組及秋水仙素處理組均會受到軟腐病菌感染，但略有程度上的差異。利用流式細胞分析比較對照組與WC09及WC26變異株DNA含量差異，其2C分別為5.02、5.06 pg及5.08 pg，顯示秋水仙素處理並未對WC09及WC26變異株造成染色體加倍的情形，推測性狀變異可能是在基因層次上的變化導致。
Zantedeschia aethiopica (L.) Spreng. is a perennial bulbous flower of the genus Zantedeschia belonging to the family Araceae. In this research, colchicine was used to induce mutation of the white flowered calla lilies ‘Larger White’ for increasing the diversity of ornamental traits and resistance to bacterial soft rot. The shoot basal discs were soaked in 0.01%, 0.05% and 0.1% colchicine for 24 hr of incubation, ddH2O as the control, and cultured in the shoot induction medium to induce shoot formation, and then subcultured in the development medium to select the regenerated mutants. The results showed that 0.05% and 0.1% colchicine treatments significantly suppressed the height of the regenerated plants in vitro. However, 16 weeks after ex vitro acclimatization, the colchicine treated plants (44.0-49.6 cm) showed significant differences compared to the control plants (38.3 cm). Colchicine treated plants were investigated for ornamental traits, heat tolerance and resistance to bacterial soft rot in order to select mutants that met the breeding objectives of this experiment. After 3 years of trait survey, the 0.1% colchicine treated plants No. WC09 and WC26 were selected for their ornamental traits of white spathe with green tips, and the trait was stable. The heat stress survey results showed that the PSII maximum photochemical efficiency (Fv/Fm) of both control and colchicine treated plants were seriously inhibited under high temperature (>37℃) conditions in the greenhouse, except the 0.01% colchicine treated plants No. WA12 and 0.1% colchicine treated plants No. WC15 and WC 27, where Fv/Fm was still maintained at 0.61-0.70. The thermal imaging results showed that several plants had good leaf temperature dispersion with an average leaf temperature of 34.08-36.6℃ under high temperature in the greenhouse. The results showed that both the control and colchicine treated plants were susceptible to soft rot infection, but there were differences in the degree of severity. Finally, flow cytometric analysis was used to compare the DNA content of ‘Larger White’, WC09 and WC26 mutants, with 2C of 5.02, 5.06 and 5.08 pg, respectively, showing that they differed in DNA content, however there was no chromosome doubling in WC09 and WC26 mutants. |
