本試驗以甘藷(Ipomoea batatas)誘變品系(P、13、17、87、89)與對照品種「台農57號」、「紅心尾」為材料，分別於組織培養、盆栽及田間三方面進行鹽分逆境試驗，分析甘藷於鹽分逆境下之外表型性狀及生理反應，以評估參試品系(種)之鹽分耐受性。試驗結果顯示，不同誘變品系之耐鹽指數(salt tolerance index; STI)因不同性狀而異，且隨鹽分濃度增加而下降；組培苗期性狀於0.5%鹽分濃度下表現穩定，當鹽分濃度達1.0%時，甘藷生長明顯受到抑制，其中誘變品系以13、89號之根長表現最佳。此外，盆栽試驗結果顯示，甘藷以150 mM NaCl處理下塊根重量表現穩定，以誘變品系87號之STI為最高，且甘藷塊根累積大量Na+及麥芽糖含量增加，推測為參試品系具較強耐鹽性之原因。進一步評估田間試驗之結果，鹽分逆境對甘藷地上部之負面影響較輕微，而對根部有較大之負面效應，導致甘藷產量降低，但減產程度因不同品系(種)而異，其中以「紅心尾」、P及87號產量顯著較高。綜合所有試驗結果，在鹽分逆境條件下，甘藷誘變品系P、87號於整個栽培期可正常生長且塊根產量較高，顯示兩品系有較高之鹽分耐受性，可供台灣未來育種選用之耐鹽甘藷雜交親本。

In this study, the mutants (P, 13, 17, 87, 89), ‘TN57’ and ‘Hong Xin Wei’ of sweet potato (Ipomoea batatas) were used as experimental materials. The salt stress was conducted in three aspects: tissue culture, potted trial and field experiment. The physiological and phenotype responses of sweet potato under salt stress were analyzed to evaluate the salt tolerance of the mutants. The results showed that different mutants responded differently to salt stress, and their salt tolerance index (STI) varied with different traits and decreased with increasing salt concentrations. The seedlings of tissue culture for mutants performed stably at 0.5% and was significantly inhibited at 1.0% salt concentration. Among them, the root length of No. 13 and No. 89 of mutants performed best. In addition, the results of the potted experiment showed that the root weight of sweet potato was stable under 150 mM salt stress, and the STI of the mutagenic line, No. 87, was the highest. It was worth noting that under 150 mM salt stress, sweet potato accumulated large amounts of Na+ and maltose content in the roots, which might be the reason to explain why the mutants had strong salt tolerance. Further evaluation in the results of the field experiment showed that the salt stress had a slight negative impact on the shoots of sweet potato, but had larger negative effect on the roots, and it caused to the decreasing of yield for sweet potato. However, the degree of yield reduction varied with different genotypes. Among them, ‘Hong Xin Wei’, P and No. 87 were significantly higher. In the potted trial and the saline soil field experiment, the sweet potato mutant P and No. 87 could grow normally and had higher yields throughout the whole cultivation period. It indicated that the two lines had higher salt tolerance and could be used as the experimental materials of salt-tolerance in the breeding program of sweet potato.