本研究針對13種山藥不同品種系塊莖之性狀與產量進行調查與比較,同時進行不同山藥塊莖物理與生化性質以及RAPD之分析,配合不同品種系塊莖抗氧化酵素活性之比較,可明確區分山藥品種系間各項特性之差異。本研究另以強迫餵食方式,進行台農2號山藥嫩芽之急性毒性測試,可確知山藥嫩芽是否安全無慮。本研究之試驗結果可供山藥品種篩選、栽培生產、加工與醫藥利用之參考。山藥不同品種系中以台農2號、大葉壽豐品系、二刺品系、大汕三品系及中國長品系等之塊莖產量表現最為優異,公頃產量皆達34 t/ha以上,其中大汕三品系及二刺品系另具有很高之過氧化酵素活性;青森品系含有高量之P、K、Ca、Mg、Fe、Mn、Cu、Zn,且塊莖亦具頗高之過氧化酵素活性,惟其產量僅為8 t/ha。由山藥台農2號嫩芽對造成白鼠急性毒性之試驗結果可知,強迫餵食組之鼠隻均不產生任何臨床症狀,亦不造成白鼠死亡,台農2號之嫩芽可歸類為無毒或少毒性類。利用篩選之隨機引子prime # 31 : 5'TGTCCGGGTG3',可在DNA層次明確區分山藥各品種系。經由RAPD分析所得之23條DNA片段中,其中3條,即587bp、834bp及1,045bp,在參試山藥15樣品之出現率依次為73.3%、66.7%及80.0%,其他20條具有多型性差異特色,有11條僅存於單一山藥品種系中,可藉以鑑別山藥不同品種系;而片段587bp不存於青森、黃藥及大汕品系;基隆品系獨具956bp及1,123bp;黃藥品系獨具556bp及802bp,且強度皆在22以上,皆可利用來與其他山藥品種系區隔及判別。A total of 13 Dioscorea genotypes had been cultivated, analyzed, and evaluated at Taiwan Agricultural Research Institute (TARI). The results obtained from comparison test on the varietal characters, yield potential, and phytochemical properties of these Dioscorea plants indicated that TNG2, 70W42, 70W47, 70W35, and 80W02 might be the most promising lines due to their high yield potential over 34 t/ha, among them 70W35 and 70W42 had a higher peroxidase activity than others. Yam line 70W49 possessed more mineral elements and also a higher peroxidase activity, but a lowest yield of 8 t/ha. The acute toxicological effects of water crude extracts of TNG2 buds administered in single dose of 5,000 mg/kg (maximal test threshold) were also evaluated. No gross abnormalities were noted in any organs of the treated animals at the necropsy. The TNG2 buds belonged to one of non- or less-toxic products.
In order to assess and distinguish the genetic diversity of all the Dioscorea species used in this experiment at DNA level, the Dioscorea samples were detected by RAPD (random amplified polymorphic DNA) technique. Total 23 polymorphic DNA fragments were scored for all materials tested using primer #31:
5'TGTCCGGGTG3', a random 10 bp primer selected from 35 primers used in TARI. Among these fragments, 11 fragments existed only in each of Dioscorea samples. 587 bp didn’t exist in 70W49, 70W37, and 70W33. 956 bp and 1,123 bp existed only in 70W43, and 556 bp and 802 bp only in 70W37. These fragments could be used as useful markers for distinguishing the genetic diversity of all the yam species used in this experiments