不同生境甘草的生态型研究

采用SDS-PAGE电泳的方法,对5种不同生境的甘草(G ly cy rrh iza ura lensis F isch.)幼苗进行了同工酶过氧化物酶(POD)、酯酶(EST)、乳酸脱氢酶(LDH)和苹果酸脱氢酶(M DH)]研究,并利用PEG 6000进行了水分胁迫的生理响应实验.同时,对种植在相同生境下的2年生子代植株的地上部形态特征进行了观测.结果表明,5种生境的甘草至少已分化为2种生态型,且与它们的生境有显著的相关性,生长在生境干燥度较大的民勤甘草(M G)和酒泉甘草(JG)为一类,其幼苗的耐旱能力较强,而生长在干燥度相对小的大兴甘草(DG)、沙坡头甘草(SG)以及内蒙甘草(NG)归为另一类,幼苗的耐旱能力也低于前者,甘草生境中气候因素的水因子可能是影响其生态型分化的主导因子.由本研究结果得出以下推论,不同生境甘草的生态型分化是其适应环境进化的结果,甘草可能是甘草属的先锋种,由于长期适应不同的生态环境而产生了趋异变化,并形成了不同的生态型乃至新种.

Ecotypes of Glycyrrhiza uralensis in Different Habitats

Young liquorice(Glycyrrhiza uralensis) seedlings in five different habitats were used for investigating their POD,EST,LDH and MDH isoenzymes by SDS-PAGE and conducting their water stress experiment with PEG 6000;In the meantime,aboveground morphologies of two year old liquorice plants in filial generations were observed.The results showed that liquorices in five different habitats differentiated into at least two ecotypes,which was significantly correlated with their habitats;MG liquorice and JG liquorice grew in habitats with higher aridity falling into one type and their young seedlings had high drought-tolerating capability,but DG liquorice and SG liquorice and NG liquorice belonged to the other type and their seedlings had lower drought tolerance than the former seedlings;of all climatic factors in liquorice habitats,water was probably the dominating factor affecting the differentiation of liquorice ecotypes.It is deduced from the results of this study that the ecotypes of liquorices in different habitats are the results of their evolution by adapting to environments,and liquorice is probably the pioneering Glycyrrhiza species diverging due to its long term adaptation to different environments and thus forming different ecotypes and even new species.