英文摘要 |
Chilling stress causes great damages to the quality and yield of sweet potato leaves. The injured leaves would appear wilted, water-soaked and yellow, with patches of necrosis. The aim of this experiment was to select chilling tolerant cultivars of sweet potatoes. Five sweet potato cultivars were observed at 6 in the dark for 0, 3, 5, 7, 9 and 15 h, and then subsequently kept at 25 for 24 and 48 h for recover. The total chilling injury indices of ‘Japanese’, ‘Big leaves’, ‘Tainung 71’, ‘Yellow leaves’ and ‘Cracked leaves’ were 7.31, 8.13, 6.75, 14.44 and 12.22, respectively, while their total recovery indices were 5.47, 3.00, 5.10, 10.15, and 7.49, respectively. The results demonstrated that ‘Japanese’, ‘Big leaves’ and ‘Tainung 71’ leaves exhibited more chilling tolerance, compared to ‘Yellow leaves’ and ‘Cracked leaves’. ‘Tainung 71’ maintained at 6 for 15 hours and then recover for 48 hours (R 48 hr) showed significant increase of Fv/Fm, and the plants kept at 6 for 9 and 15 hours had higher SOD activity. |