利用莖頂組織超低溫冷凍處理法去除甘藷病毒之研究

Abstract

本研究試驗材料為甘藷[Impomoea batatas ( L ) Lam.]栽培種「台農57 號」、「台農66 號」與野生種「WT248」、「WT427」分別感染甘藷羽狀斑駁病毒(SPFMV)、甘藷病毒G (SPVG)與甘藷黃矮病毒(SPCSV)，取病毒株莖頂組織為材料，以藻膠包埋玻璃質化法進行超低溫冷凍保存，於回復生長培養基(即MS 基本鹽類)添加1 μM NAA, 0.5 μM BA, 0.5 μM Kinetin,30 g L-1 蔗糖及9.4 g L-1 Difco agar。結果顯示，「台農66 號」及「WT427 」可獲得植株成活率最佳13.115.2%，而「台農57 號」僅獲得2.2%；若以1 μM IAA 替代NAA，並且將BA 濃度提高1 倍，則「台農57 號」的植株成活率提高為44.6%，但野生種兩品系的植株成活率降低為011.1%；以感染病毒之甘藷進行超低溫冷凍處理法去除病毒的試驗顯示，栽培種「台農57 號」、「台農66 號」及野生種「WT248」之再生株以RT-PCR 均未測到上述三種病毒，去病毒率為100%，野生種「WT427」的9 個再生株中，5 個測到甘藷病毒G，去病毒率為44.4%。 Sweet potato [Ipomoea batatas (L) Lam.] cultivars/lines, ‘Tainung No. 57 (TNG57)’,‘Tainung No. 66 (TNG66)’, ‘WT248’ and ‘WT427’ infected with Sweet potato feathery mottle virus (SPFMV), Sweet potato virus G (SPVG) and Sweet potato chlorotic stunt virus (SPCSV) were cultivated at Wufeng District, Taichung City, for the field experiment. The treatment of cryotherapy was applied to the shoot tips of infected plants for preservation. The preserved shoot tips were put into the survival medium which consisted of MS (Murashige and Skoog) basic salted medium and supplemented with 1 μM NAA, 0.5 μM BA, 0.5 μM Kinetin, 30 g L-1 sucrose, and 9.4 g L-1 Difco agar. The shoot regeneration rates were 13.1-15.2% from in itro-grown sweet potato of ‘TNG66’ or ‘WT427’, and was 2.2% for ‘TNG57’. In the case of 1 μM IAA replaced with NAA and concentration of BA was increased twice in the survival medium, the shoot regeneration rate enhanced to 44.6% for ‘TNG57’, but decreased to 0-11.1% for 2 wild types of sweet potato. By multiplex RT-PCR, SPFMV, SPVG and SPCSV were undetectable in all regenerated plantlets of ‘TNG 57’, ‘TNG 66’ and ‘WT248’ (100% virus eradication); however, SPVG was detected in 5 out of 9 regenerated plantlets of ‘WT427’.