芒和荻种子对复合盐碱胁迫的生理响应

Effects of complex salt-alkali stress on the physiological characteristics of Miscanthus sinensis and M. sacchariflora

关键词:  芒, 荻, 复合盐碱胁迫, 种子, 生理特性

Key words:  Miscanthus sinensis, M. sacchariflora, complex salt-alkali stress, seed, physiological characteristics

摘要:

土壤盐碱化在世界范围内普遍存在,日益严峻的盐碱化形势严重威胁着植物的生长发育。芒(Miscanthus sinensis)和荻(Miscanthus sacchariflora)作为能源植物具有良好的经济效益和生态效益,并且在城市园林中已得到广泛应用。该研究以引种自辽宁省本溪阿家岭的芒和哈尔滨市太阳岛的荻为对象,模拟我国东北大庆盐碱地的低(浓度1、2)、中(浓度3)、高(浓度4、5)浓度土壤环境,分别对芒和荻的种子进行复合盐碱胁迫处理,对芒和荻的种子萌发情况进行研究。结果表明:(1)复合盐碱胁迫处理下,芒种子的发芽率随着复合盐碱浓度的升高而降低,发芽势、活力指数、发芽指数、胚根长度、胚芽长度、胚根鲜重、胚芽鲜重和耐盐碱指数均先升高后降低; 荻种子的发芽率、发芽势、活力指数、发芽指数、胚根长度、胚芽长度、胚根鲜重、胚芽鲜重和耐盐碱指数均随着复合盐碱浓度的升高而降低。(2)芒和荻的种子能够抵抗低、中浓度的复合盐碱胁迫处理,当高浓度的复合盐碱胁迫处理时,各项指标均下降明显,且芒种子的各项指标均优于荻种子,说明芒种子比荻种子更耐盐碱。该研究结果基本界定芒荻种子的复合盐碱耐受范围,为今后芒荻类能源植物的耐盐碱性筛选和在园林中的应用提供了理论依据。

Abstract:

Today, soil salinization is prevalent in the world. The increasingly salinization seriously threatened the growth and development of plants. With good economic and ecological benefits, Miscanthus sinensis and M. sacchariflora which are energy plants have been widely used in urban landscape architecture. Taking M. sinensis, introduced from Ajialing of Benxi, Liaoning Province, and M. sacchariflora, introduced from Sun Island of Harbin, as materials, and simulating the saline-alkali soil environment of Daqing in northeast of China which include low(concentration 1,2), middle(concentration 3)and high concentration(concentration 4, 5), we studied the seed germination of M. sinensis and M. sacchariflora when they were in the complex salt-alkali stress treatments. The main experiment results were as follows:In the complex salt-alkali stress treatment, the germination percentage of M. sinensis seed decreased with the complex salt-alkali concentration increasing, but other indexes of M. sinensis seed included the germination energy, seed vigor index, germination index, radicle length, germ length, radicle weight, germ weight and drought-salt index increased at first and then decreased. All the indexes of M. sacchariflora seed included the germination percentage, germination energy, seed vigor index, germination index, radicle length, germ length, radicle weight, germ weight and drought-salt index decreased with the mixed alkali-saline concentration increasing. It was found that the two kinds of seeds could resist complex salt-alkali stress of middle and low concentration. When they were in high concentration, all the indexes decreased obviously. But each index of M. sinensis seed was superior to that of M. sacchariflora seed which could indicate that the salinity tolerance of the former was stronger than the latter. The study basically defined the complex salt-alkali tolerance range of M. sinensis and M. sacchariflora seeds. This provides a theoretical basis for the screen of saline-alkali tolerant plant and applications in landscape of energy plants like M. sinensis and M. sacchariflora in the future.