以電解質滲漏率評估四種萵苣幼苗之耐熱性

Assessment on the Heat Tolerance of Plug Seedlings of Four Lettuces by Electrolyte Leakage Ratio

李志中(Zhi-Zhong Li) ； 洪進雄(Chin-Hsiung Hung)

《植物種苗》 12卷1期 (2010/03) Pp. 1-12

https://doi.org/10.30077/SN.201003.0001

摘要

本研究以電解質滲漏率為工具，評估細胞膜受到熱破壞之溫度及時間，探討萵苣品種（葉萵苣‘V-155’、尖葉萵苣‘V-305’、紅菲萵苣‘葉萵41’、皺葉萵苣‘LS-005’）之耐熱性。萵苣幼苗取第三葉及第五葉打洞成小圓葉片，在30-70℃水浴中處理1-8小時，電解質滲漏率呈S型反應曲線，所有處理中以第三位葉在50℃水浴處理最能區分出耐熱及熱敏感品種之差異。耐熱品種（葉萵苣‘V-155’）於高溫50℃水浴下第1小時之電解質滲漏率為16.4％；熱敏感品種（皺葉萵苣‘LS-005’）為22.8％，不同高溫時間對葉片細胞膜熱穩定性均具有破壞能力，耐熱品種之電解質滲漏率明顯低於熱敏感品種；在相同熱破壞溫度下，處理時間越長，電解質滲漏率越高。不同處理之電解質滲漏率以50℃水浴下60-80分鐘差異最顯著，四品種之電解質滲漏率由低而高可區分為尖葉萵苣‘V-305’＜葉萵苣‘V-155’＜紅菲萵苣‘葉萵41’＜皺葉萵苣‘LS-005’；尖葉萵苣‘V-305’及葉萵苣‘V-155’為耐熱品種，紅菲萵苣‘葉萵41’及皺葉萵苣‘LS-005’為熱敏感品種。

關鍵字

萵苣 ； 高溫逆境 ； 耐熱性 ； 電解質滲漏率

並列摘要

The heat-tolerance of four lettuce cultivars (Leaf lettuce'V-155', asparagus lettuce'V-305', lettuce-41, Curled lettuce'LS-005') were evaluated by electrolyte leakage, and the damage of cell membrane were assessed by the duration under heating temperature. Plug seedling at 5-6 true leaf stage, the 3rd and 5th leaf of each cultivar were punched to 1 cm round leaf disc, then placed 5 leaf discs in a water bath at 30-70℃ for 1-8 hours and at 50℃ for 1-8 hours for measure electrolyte leakage. The curve of electrolyte value leakage was sigmoidal in all treatments. The value of the 3rd leaf at 30-70℃ water bath was able to distinguish the heat-tolerant and heat-sensitive cultivars. Electrolyte leakage value of heat-tolerant leaf lettuce was 16.4% in the water bath at 50℃ for one hours; but heat-sensitive (curled lettuce) was 22.8％. Thermal stability of the cell membrane was dependent on the heating temperature and its duration. Electrolyte leakage value of heat-tolerant cultivars was lower than those of the heat-sensitive cultivars. The damage of cell membrane (electrolyte leakage ratio) at the same temperature showed that the longer the treated period, the higher the electrolyte leakage ratio. The heat tolerant of four lettuce cultivars could be separated by electrolyte leakage value under water bath at 50℃ for 80 minutes. The electrolyte leakage ratio of four lettuce cultivars were ranked as follow: asparagus lettuce'V-305'＜Leaf lettuce'V-155'＜lettuce-41＜Curled lettuce'LS-005'. Asparagus lettuce as well as leaf lettuce were heat-tolerant and leaf lettuce and lettuce-41were heat-sensitive.

並列關鍵字

Lettuce (Lactuca sativa L.) ； high temperature stress ； heat tolerance ； electrolyte leakage value