温度、PEG处理和盐胁迫对小车前种子萌发的影响  

Effects of Temperature,Stress Induced by PEG-8000 and NaCl Solutions on Seed Germination of Plantago minuta(Pall)

作　　者：田美华[1] 唐安军[1] 

机构地区：[1]重庆师范大学生命科学学院,重庆400047

出　　处：《重庆师范大学学报（自然科学版）》2011年第6期67-71,共5页Journal of Chongqing Normal University:Natural Science

基　　金：重庆市教委科研项目(No.KJ100610);重庆师范大学博士启动金项目(No.09XLB016)

摘　　要：本研究旨在探讨短命植物小车前(Plantago minuta Pall.)种子的休眠特性及其对温度、干旱和盐胁迫等因子的响应特点。在10、152、02、5和30℃的不同恒温条件以及每日15、25℃各12 h的变温条件下,新鲜的小车前种子萌发率较低,其最高萌发率为15%。在经60 d的干藏后,种子休眠被解除;已解除休眠的种子的萌发是温度依赖的,以20℃为最佳,此时萌发率为97%。解除休眠后的小车前种子萌发率随PEG-8000和NaCl溶液浓度的升高而降低。结果表明,小车前种子具初级休眠,且在长期适应环境过程中形成了独特的生态适应性;对干旱和盐胁迫有一定的耐性。进一步推知,短命植物小车前特定的休眠特点和萌发模式是其适应与进化的重要基础;此种植物在严重干旱发生早期完成生活史,是避旱型植物。The present study aimed at investigating dormant characteristics and responses to germination temperature, drought and salt stress of Plantago minuta seeds. Freshly harvested seeds of P. minuta did not germinate well and showed innate dormancy at broad range of constant temperatures （ 10, 15,20, ？.5 and 30 ℃ ） and an altering temperature of 25/15 ℃ with a 12 h photoperiod. However, the dormancy was broken after 60 d dry storage at 4 ℃. Obviously, the germination was temperature-dependent and the optimum temperature was 20℃ with the germination of 97% in light. Also, the decrease in the final germination percentages was observed with increase in concentration of both PEG-8000 and NaCI solutions. It suggested that P. minuta produces innate dormant seeds and develops its unique ecological adaptation although this species is able to tolerate weak salt stress and water deficiency. Based on these results above, it could be inferred that the particular ,dormant characteristics and germination pattern underlie its adaptation to the desert environment and evolve in the field. Moreover, P. minuta has an escape strategy for a short life history which often ends at the beginning of badly natural drought in the habitat.

关 键 词：短命植物 种子休眠 萌发 生态适应性 NaCl胁迫 渗透胁迫 温度 小车前 

分 类 号：Q945.79[生物学—植物学] Q945.34