入侵植物北美车前种子粘液的吸水特性及其对干旱胁迫的萌发响应  

Water absorbance features of seed mucilage of an invasive plant,Plantago virginica,and its germination response to drought stress

作　　者：罗辉[1] 闫小红[2] 周兵[2] 王宁[2] 杨佳琴[2] 

机构地区：[1]井冈山大学医学院 [2]井冈山大学生命科学学院

出　　处：《生态学杂志》2015年第8期2155-2160,共6页Chinese Journal of Ecology

基　　金：国家自然科学基金项目(31360090和31460488);江西省自然科学基金项目(20114BAB214011);江西省高等学校科技落地计划项目(KJLD12079)资助

摘　　要：北美车前（Plantago virginica）是中国南方广泛分布的一种入侵植物。为探讨北美车前种子的休眠萌发特性及种子粘液对其种子在干旱环境中萌发的作用,在室内控制条件下研究了其种子在收获后不同月份的萌发状况、粘液的吸水失水特性、有粘液种子和无粘液种子在不同渗透胁迫条件下的萌发状况。结果表明：北美车前种子有近1个月的休眠期,成熟后第2~9个月保持较高的种子萌发率（48.75%~88.75%）;北美车前有粘液种子对水分的吸收能力明显强于无粘液种子,粘液可吸收其干质量近59倍的水量;在-1.21~0 MPa渗透势胁迫下,与对照相比,有粘液种子萌发率只下降了18.58%,无粘液种子萌发率下降了62.71%;可见,北美车前种子休眠期短,萌发率高,种子粘液有较强的吸水能力,有利于种子对干旱环境的适应,从而间接增强了其入侵性。Plantago virginica is one of the widespread invasive weeds in southern China. The seed germination in different postharvest months, water absorption of seed mucilage and the ger- mination of the seeds with or without mucilage under different osmosis were studied in laboratory to assess its seed dormancy and germination properties, and the effects of the mucilage in seed germination under drought environment. The seeds of P. virginica had a dormancy period about one month and kept high germination rates 2 to 9 months after mature （48.75%-88.75%）. The water absorption ability of the seeds with mucilage was obviously higher than that of the seeds without mucilage, and the water absorbed by the mucilage was 59 times or so as its dry mass. Compared with the control, the germination rates of the seeds with mucilage and without mucilage decreased by 18.58% and 62.71% respectively under the osmosis stress from -1.21 to 0 MPa. Our experimental findings suggested that the characteristics of P. virginica such as short dormancy period and high germination rate of the seeds, and the obviously strong water absorption ability of seed mucilage, might contribute to its adaptation to the drought environment and indirectly enhance its invasive capability.

关 键 词：北美车前 萌发 粘液 吸水 干旱胁迫 

分 类 号：Q945.78[生物学—植物学]