花椰菜高溫淹水耐受性之生理指標

Physiological Index for Tolerance to High Temperature and Waterlogging in Cauliflower

花椰菜58個品種於2009年夏季種植於雲林縣二崙鄉，在花球直徑約1.5 cm時給予田間淹水處理2天，‘嬌雪’為58品種中產量最高。根據產量挑選‘嬌雪’、‘H-46　’、‘雪美45天’及‘農生45天’，另加入欣樺種苗公司極早生耐熱品系9104，於2010年夏季在臺南市安南區進行淹水處理後產量試驗，亦以‘嬌雪’產量最高，而‘農生45天’最低，故挑選‘嬌雪’與‘農生45天’進行苗期高溫淹水試驗。‘嬌雪’幼苗葉圓體細胞膜之熱致死溫度為49.4°C，比‘農生45天’之47.1°C高。‘嬌雪’幼苗在高溫及淹水逆境下，比‘農生45天’有較佳之生長能力。於高溫淹水處理後，‘嬌雪’之過氧化氫酶（catalase，CAT）與抗壞血酸過氧化酶（ascorbate peroxidase，APX）活性，比‘農生45天’較早達到顯著上升程度，清除活性氧族。結果顯示，田間夏季淹水試驗高產量的‘嬌雪’幼苗具較高之細胞膜熱穩定性、高溫淹水逆境下生長能力、與較早上升CAT與APX活性。這些生理指標或可做為選育耐高溫淹水花椰菜之參考。 Fifty-eight cauliflower cultivars were grown at Yunlin in 2009 summer. Plants were waterlogged for 2 days in the field when curd diameter was about 1.5 cm and 'Charming Snow' exhibited the highest yield. 'Charming Snow', 'H-46', 'Snow Beauty 45 days', and 'Nong-sheng 45 days' and line 9104 from Sing-flow Seed Trading Company were selected to conduct the waterlogging yield trial at Tainan in 2010 summer. Results showed that 'Charming Snow' also had the highest yield and 'Nong-sheng 45 days' the lowest. High temperature and waterlogging tolerant 'Charming Snow' and sensitive 'Nong-sheng 45 days' were selected to conduct the seedling experiments. The heat killing temperature of cell membrane in 'Charming Snow' leaf discs was 49.4°C, higher than 47.1°C for 'Nong-sheng 45 days', indicating that 'Charming Snow' exhibited higher cell membrane thermostability (CMT) and more growth than 'Nong-sheng 45 days' under high temperature and waterlogging stress. The activities of catalase (CAT) and ascorbate peroxidase (APX) in 'Charming Snow' increased earlier than 'Nong-sheng 45 days' after high temperature and waterlogging treatments. 'Charming Snow' scavenged reactive oxygen species earlier than 'Nong-sheng 45 days'. The results in summer waterlogging trials showed that high-yielding 'Charming Snow' had higher CMT, better relative growth and earlier increases of CAT and APX activities in seedlings under heat and waterlogging stress. These physiological parameters may be used as indexes for breeding heat- and waterlogging-tolerant cauliflower cultivars.