高溫季節野生番茄於淹水下之生理反應

The Physiological Responses of Wild Tomatoes to Flooding during the Hot Season

Heat and flooding are environmental stresses that inhibit tomato growth and productivity during the hot season in Taiwan. Selecting plant lines tolerant to flooding and heat would increase the productivity of tomato during the hot season. Two-month-old plants from the tomato lines Solanum pimpinellifolium L4422, S. habrochaites L3683, S. peruvianum L1947, and the tomato (S. lycopersicum L.) 'ASVEG #6' were flooded for 5 d during the hot season in Taipei. The relative water content, stomatal conductance, and chlorophyll fluorescence in the leaves, and the antioxidant contents, and activity of antioxidative and fermentative enzymes in the roots were measured. At 12 h after flooding, L1947 revealed a rapid decrease in stomatal conductance and Fm value, higher α-tocopherol content and Fv/Fm value than L4422, and higher alcohol dehydrogenase activity than that in the other three Solanum plants. The Fm values for L1947 and L3683 decreased earlier (at 12 h) than 'ASVEG #6' and L4422 (at 24 h) after flooding. The ascorbate peroxidase activity and fresh weight in L1947 root were increased at 48 h after flooding. Thus, among the four Solanum plants studied, L1947 is more tolerant to flooding during the hot season in Taipei. 高溫與淹水是抑制臺灣夏作番茄生長與生產力的環境逆境，選拔耐高溫淹水品系有助於提高夏作番茄生產力。以野生番茄Solanum pimpinellifolium L4422、S. habrochaites L3683、S. peruvianum L1947與番茄‘臺南亞蔬6號’（S. lycopersicum L.‘ASVEG #6’）2月齡植株為試驗材料，於臺北高溫季節淹水5天，期間量測植株生長、葉片之相對含水量、氣孔導度與葉綠素螢光、及根部之抗氧化物含量、抗氧化酵素及無氧呼吸酵素活性。淹水後12小時，L1947之葉片氣孔導度與Fm值快速下降，葉片Fv／Fm值與根部α-生育醇含量比L4422高、根部酒精去氫酶活性比其他三種茄屬根部高。L1947與L3683植株在淹水後，葉片Fm值下降時間（12小時）比‘ASVEG #6’與L4422（24小時）早。L1947根部之鮮重與抗壞血酸過氧化酶活性亦於淹水後48小時增加。故四種茄屬試驗材料於臺北高溫季節以L1947較耐淹水。