Effect of Putrescine Pretreatment to Roots on Growth and Lactate Metabolism in the Root of Tomato (Lycopersicon esculentum Mill.) under Root-zone Hypoxia
Effect of Putrescine Pretreatment to Roots on Growth and Lactate Metabolism in the Root of Tomato (Lycopersicon esculentum Mill.) under Root-zone Hypoxia
复制标题
DOI：
10.2503/jjshs.73.337
复制
发表时间：
2004-07
影响因子：
--
通讯作者：
K. Nada;Etsuko Iwatani;T. Doi;S. Tachibana
中科院分区：
文献类型：
--
作者：
K. Nada;Etsuko Iwatani;T. Doi;S. Tachibana
根区缺氧不耐受的番茄植物（Lycopersicon esculentum Mill.，CV. House-Momotaro）从第5叶期开始在溶解氧浓度为1 mg·L-1（低氧）或6 mg·L-1（常氧）的营养液中生长7 d。营养液中溶氧水平对根系多胺合成酶活性和游离多胺含量无明显影响。与常氧营养液相比，低氧营养液中的植物生长较差，且表现出显著的乳酸脱氢酶活性和根系中乳酸含量的增加。然而，预孵育的植物在0.5 mM腐胺含常氧营养液6小时促进根的生长，并抑制了上升的乳酸发酵的根后5天缺氧。这些结果表明，腐胺干扰低氧诱导的根系乳酸发酵，减轻了根系的低氧伤害，提高了番茄植株的根区耐缺氧能力。
Root-zone-hypoxia-intolerant tomato plants (Lycopersicon esculentum Mill., cv. House-Momotaro) were grown in nutrient solution with a dissolved O2 concentration of either 1 mg·liter-1 (hypoxia) or 6 mg·liter-1 (normoxia) for 7 days starting at the fifth leaf stage. The dissolved O2 levels in nutrient solution did not affect polyamine biosynthetic enzyme activities and free polyamine contents in the roots. Plants in hypoxic nutrient solution grew poorly and exhibited a significant increase in lactate dehydrogenase activity and lactate content in the roots compared with those grown in normoxic nutrient solution. However, preincubation of plants in 0.5 mM putrescine-containing normoxic nutrient solution for 6 hr promoted root growth and inhibited the rise of lactate fermentation in the roots after day 5 under hypoxia. These results indicate that putrescine interferes with hypoxically induced lactate fermentation in the roots; it alleviates hypoxia injury of roots and increases the root-zone hypoxia tolerance of tomato plants.