滲調處理促進結球萵苣種子發芽時endo-β-mannanase之活性

Priming Enhances endo-β-mannanase Activity in Lettuce (Lactuca sativa L.) Seeds

‘Dark Green Boston’萵苣滲調種子於27℃較未滲調者提高28.8%發芽率，發芽整齊度與平均發芽天數均縮短。‘Everglad’萵苣滲調種子於33℃時較未滲調種子提高46.1%發芽率，增加發芽整齊度，達顯著性差異。於33℃‘達豐’萵苣滲調種子發芽率較未滲調種子提高47.6%，發芽整齊度、平均發芽天數差異不顯著。利用Gel-diffusion測定種子胚根尖端珠孔區及側邊胚乳之endo-β-mannanase活性，‘Dark Green Boston’、‘Everglade’與‘達豐’萵苣滲調種子之endo-β-mannanase活性於二發芽溫度下浸潤時，以胚根尖端珠孔區之活性較高，且滲調種子活性較未滲調者高。‘Dark Green Boston’萵苣滲調種子於20℃時產生與endo-β-mannanase為標識之相同位置編號2、3、4之蛋白質，浸潤於27℃使未滲調種子產生少量編號1及3蛋白質。 At 27℃, the germination rate of primed ‘Dark Green Boston’ seeds was 28.8% greater than that of unprimed seeds. In addition, priming decreased the GT90-10 and the mean number of days to germination (MDG). At 33℃, priming increased the germination of ‘Everglade’ seeds by 46.1% and shortened GT90-10 by 0.4 days. At 33℃, priming increased the germination of ‘Mesa 659’ seeds by 47.6%, but it had no significant effect on GT90-10 and MDG. During lettuce seed germination, the endo-β-mannanase activity was measured with a gel-diffusion assay. In the primed lettuce seeds of all the three cultivars germinating at high or low temperatures, the endo-β-mannanase activity was higher in the micropylar region than in lateral regions. In addition, activity was higher in primed seeds than in unprimed ones. Based on two-dimensional gel electrophoresis fluorographs, primed ‘Dark Green Boston’ seeds imbibed at 20℃ produced protein No. 2, 3 and 4. Primed seeds imbibed at 27℃ made unprimed seeds produce spots of protein No. 1 and 3.