【摘要】 以河砂为基质分别把50,100,150,200mmol/L的NaCl,Na2SO4,NaHCO3和Na2CO3配制成20个不同比例的处理组合,研究混合盐胁迫对蒲公英出苗和幼苗生长的影响,使蒲公英种子和幼苗在胁迫条件下成苗。结果表明,蒲公英种子的出苗率、幼苗地上地下部分长度和幼苗的鲜重不同程度受到影响,当溶液中NaHCO3与Na2CO3比例增大时,出苗率和地下部分受抑制程度强于地上部分。各种混合盐溶液浓度达到100～150mmol/L时仍有部分蒲公英出苗,当浓度为200mmol/L时蒲公英出苗完全受到抑制。当浓度为50mmol/L,且各混合盐溶液比例为NaCl∶Na2SO4∶NaHCO3∶Na2CO3=1∶2∶1∶0时,对蒲公英出苗有促进作用。当浓度为100～200mmol/L,且混合盐溶液比例为NaCl∶Na2SO4∶NaHCO3∶Na2CO3=1∶1∶0∶0时,出苗受到严重抑制,达到极显著水平(P<0.01)。蒲公英对混合盐胁迫表现出一定的耐受性,适当浓度盐溶液胁迫有助于促进蒲公英出苗。碱性盐对蒲公英出苗的胁迫作用大于中性盐,增大混合盐溶液浓度对蒲公英出苗的胁迫作用大于增大溶液中碱性盐浓度造成的胁迫作用。更多还原

【Abstract】 The objective of experiment was to study the effects of mixed salt stress on seed germination and seedling growth of Taraxacum mongolicum Hand-Mazz taking 20 different proportion compound of 50,100,150,200 mmol/L NaCl,Na2SO4,NaHCO3 and Na2CO3 and using river sand as a substrate,seed germination and seedling growth of T.mongolicum were tested under these stress conditions.The result showed that the emergence rate,seedlings on the underground part and fresh weight were different.When the solution alkaline salt of NaHCO3,Na2CO3 ratio increased,the rate of emergence and the underground parts of the degree of suppression were greater than the part on the ground.When the mixed salt solution concentration was 100-150 mmol/L,there still were some seedlings of T.mongolicum germinated there.When the concentration was 200 mmol/L,the emergence rate of T.mongolicum was completely inhibited.The concentration was 50 mmol/L mixed with NaCl∶Na2SO4∶NaHCO3∶Na2CO3 =1∶2∶1∶0,it impoved the emergence.When concentration was 100-200 mmol/L mixed with NaCl∶Na2SO4∶NaHCO3∶Na2CO3 =1∶1∶0∶0,emergence percentage were seriously inhibited.T.mongolicum tolerates to mixed salt stress and appropriate mixed salt stress help emergence of T.mongolicum.Stress effect of alkaline salts is greater than that of the neutral salt.The stress effect of increasing the concentration of mixed salt solution is greater than that of alkaline salt.更多还原