不同品系間甘薯葉都及塊根胰蛋白脢抑制因子活性之差異

Cultivar Differences in Trypsin Inhibitory Activities of Sweet Potato Leaves and Tuberous Roots

利用蛋白質膠體電泳技術分析不同品系間甘薯（Ipomoea batatas Lam.）胰蛋白脢抑制因子的活性，發現塊根及葉部的胰蛋白脢抑制因子活性在不同品系間有所差異。甘薯的葉都組織中，台農9號、34號、57號和65號均有兩種胰蛋白脢抑制因子，分子量為31kDa及14kDa，其中65號的胰蛋白脢抑制因子活性最強，9號的活性最弱。而在台農27號、34號、57號和65號的甘薯塊根中，均有兩種胰蛋白脢抑制因子，分子量為21kDa及31kDa，57號另有一個33kDa的胰蛋白脢抑制因子。其中27號和57號的胰蛋白脢抑制因子活性較強，34號和65號的活性較弱。此結果顯示，葉部之胰蛋白脢抑制因子之活性高低，與田間栽培試驗的抗蟲能力有正相關。經由西方轉漬法（Western blotting）分析甘薯塊根與葉部組織的胰蛋白脢抑制因子，顯示葉部之胰蛋白脢抑制因子和塊根有所不同。

Trypsin inhibitor (Ti) activities in sweet potato (Ipomoea batatas Lam.) leaves and roots from five local cultivars were analyzed on 15% SDS-PAGE. At qualitative level, it showed that two forms of Ti were present in both organs, with Mr. 31,000 Da and 14,000 Da in leaves, and Mr. 31,000 Da as well as 21,000 Da in roots, respectively. At quantitative level, the Ti activities varied among these cultivars. The level of trypsin inhibitory activity was closely related with pest resistance. More Ti activity conferred strong insect resistance on several cultivars, i.e. Tainong 34 and 65. Finally, the data of immunostain with anti-sporamin antiserum demonstrated that Tis from leaves were different from those of roots in sweet potato.