【摘要】 【目的】探讨钙施用时期对提高番茄耐盐性的作用。【方法】以番茄辽园多丽为材料,研究不同时期(提前3d、同时、延后3d)营养液增施Ca2+(10mmol·L-1)对NaCl(100mmol·L-1)胁迫下番茄幼苗的生物量、外渗电导率、相对含水量、脯氨酸含量、可溶性糖含量、丙二醛含量、Ca2+-ATPase活性的影响,探讨Ca2+对盐胁迫伤害的缓解作用。【结果】在各处理中,100mmol·L-1NaCl(T2)胁迫条件下,番茄幼苗的生长较对照(T1)显著受到抑制,上述相关生理代谢受到影响;提前3d(T5)营养液增施钙,在NaCl胁迫时停止增施钙,结果对缓解盐胁迫伤害无显著作用;在NaCl胁迫情况下同时增施10mmol·L-1CaCl2(T3),显著缓解了盐胁迫对番茄幼苗的伤害,但提前3d增施钙处理(T4),未能进一步显著增强这种缓解作用。【结论】盐胁迫同时增施外源Ca2+具有显著缓解NaCl盐胁迫对番茄幼苗伤害的作用,但盐胁迫之前增施外源Ca2+不具备这种作用,可见外源钙提高番茄耐盐性不是诱导效应,而主要是与Na+共存的离子竞争效应。更多还原

【Abstract】 【Objective】 The objective of this study was to investigate the effects of timing of exogenous calcium application on the alleviation of tomato injury of salt stress. 【Method】 The exogenous calcium (10 mmol·L-1) was applied to the growth medium of tomato (Lycopersico esculentum Mill. cv. Liaoyuanduoli) seedling before three days,together with,or after three days of NaCl (100 mmol·L-1) application. Some physiological and biochemical responses (amount of growth ,extravasation conductivity,relative water content,proline content and soluble sugar content,malondialdehyde (MDA) content,Ca2 +-ATPase activity) were studied,and then Ca2+ application on the alleviation of salt stress was investigated. 【Result】 The growth of tomato seedling was suppressed and physiological metabolism of tomato was going worse under 100 mmol·L-1NaCl (T2)stress compared with the control (T1). Solution without NaCl or 10 mmol·L-1CaCl2 was added 3 d(T5) immediately before being grown in the solution with 100 mmol·L-1 NaCl,alleviation of NaCl stress was not significantly achieved. Solution with 100 mmol·L-1 NaCl and 10 mmol·L-1CaCl2 (T3) significantly alleviated the harm of salt stress to tomato seedlings,but solution added with CaCl2 3 d before being grown in the solution with 100 mmol·L-1 NaCl and 10 mmol·L-1 CaCl2 (T4),the role of alleviation of salt stress did not increase compared with T3. 【Conclusion】 Effects of exogenous calcium application on the alleviation of salt stress of tomato were significantly achieved,but the alleviation of salt stress was achieved when Ca2+and Na+ coexisted in the growth medium,and no effect of Ca2+ on salt stress was observed when Ca2+ was applied before NaCl stress. The alleviation of salt stress on tomato was not Ca2+-induced,but the competitive effect of coexistence of Ca2+ and Na+.更多还原