Cold Water Treatment Promotes Ethylene Production and Dwarfing in Tomato Seedlings

• Main Authors: Jing-Yueh Huang, 黃景岳
• Other Authors: Chin-Ho Lin
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/84343545425689138231

碩士 === 國立中興大學 === 植物學系 === 89 === Tomato seedlings treated with cold water (5°C) once a day, starting 14 days after sowing, were only 80% that of the controlled (25°C) plant height after 21 days. The dwarfing effect was most conspicuous on the first internode length. The hypocotyl diameter, fresh and dry weight of shoot was not significantly affected. 5°C water treatment effectively induced ethylene production with a peak duration 60-90 minutes after the cold water shower. Shoot segments excised above the first node have highest rate of ethylene production. A single treatment of 5°C water on Day 21 results in an ethylene production rate of 19.6 nl/g F.W./hr, compared to 3.4 nl/g F.W./hr for 25°C control seedlings (an increase of 5.8 times). Fourteen-day-old seedlings receiving 2 weeks of 5°C cold water treatment is equivalent to pre-treatment with 3 ppm of ethephon (2-chlorophosphonic acid); and 1 nl/L 1-methyl-cyclopropene (1-MCP) pre-treatment is sufficient to block the ethylene action induced by 5°C cold water treatment. There were no distinct differences in hypocotyl diameter and endogenous ethylene production rate among those treatments. It is inferred that cold water treatment-induced dwarfism of tomato seedlings is mediated through ethylene action.