【摘要】 为探究10种高原乔木对低温胁迫的生理响应和抗寒性差异,以栽植苗木的一年生枝条为材料,研究低温处理(-5℃,-15和-25℃)对其相对电导率、丙二醛(MDA)含量、超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性及脯氨酸含量的影响,并使用隶属函数法对供试树种的抗寒性进行了评价和分析。结果表明:随胁迫程度的加剧,参试树种的相对电导率均呈逐渐上升趋势;多数供试树种的SOD和POD活性呈现先升高后降低的趋势,两个酶的活性在-15或-25℃胁迫条件下达到最高;大部分树种中脯氨酸的积累随胁迫程度加剧而增加,而MDA含量则呈现先增加后减少或逐步增加的趋势。采用隶属函数法得出的抗寒性强弱顺序依次为:落叶松>青海云杉>祁连圆柏>川西云杉>油松>白榆>新疆杨>小叶杨>青杨>旱柳。更多还原

【Abstract】 To explore physiological response to low temperature stress and cold resistance difference of 10 plateau trees, using the annual branches of plant seedlings for the material, we studied the effects of low temperature treatment(-5℃,-15℃ and-25℃) on the relative conductivity, malondialdehyde(MDA) content, superoxide dismutase(SOD) activity, peroxidase(POD) activity and proline content, and evaluated and analyzed cold resistance of the tested trees by the membership function method.The results showed that with the intensification of stress, the relative electrical conductivity(REC) of all the tested trees showed a gradually increasing trend, the activity of leaf superoxide dismutase(SOD) and peroxidase(POD) in most of the tested trees increased first and then decreased, and the activities of the two enzymes reached the highest under-15℃ or-25℃ stress.The accumulation of proline in most tree species increased with the intensified degree of stress, while the content of MDA increased first and then decreased or gradually increased.The order of cold resistance from high to low obtained by the membership function method was as follows: Larix gmelinii>Picea crassifolia>Sabina przewalskii>Picea likiangensis>Pinus tabuliformis>Ulmus pumila>Populus alba var.pyramidalis>Populus simonii>Populus cathayana>Salix matsudana.更多还原