【作者】 李彦慧；

【导师】 杨建民； 李保国；

【作者基本信息】 河北农业大学 ， 森林培育， 2008， 博士

【摘要】 以盆栽2年生紫叶李（Prunus cerasifera var atropupurea）、紫叶矮樱（Prunus×cistenena‘pissardii’）、黑杆樱李（Prunus wrasifers‘nigra’）及美人梅（Prunus×bliriana‘Meirenmei’）为试材,采用简易静态熏气系统,详细研究了不同浓度SO₂处理、17.1 mg.m^-3SO2持续处理以及外源NO对SO₂处理下李属彩叶树种形态解剖构造和生理特性的影响,旨在阐明李属彩叶树种耐SO₂污染机制,对丰富植物耐SO₂研究的理论、科学评价植物抗SO₂污染能力以及指导园林绿化科学选择树种等具有重要理论和现实意义。研究结果如下:1采用模糊数学隶属度公式对叶片膜透性,MDA、脯氨酸和可溶性蛋白、POD、SOD和CAT、pH、吸硫量等指标的测定值进行转换并进行相关分析,得出4树种耐SO₂能力由强到弱的顺序为紫叶李、黑杆樱李、美人梅、紫叶矮樱。2不同浓度SO₂处理下,紫叶李和紫叶矮樱叶片可见伤害症状表现不同,以SO₂浓度17.1mg.m^-3为例,紫叶李只有叶片背面边缘产生轻微的退色斑,而紫叶矮樱叶片正面和背面均有大面积明显的退色斑,且叶片背面伤痕更严重。3不同浓度SO₂处理对紫叶李和紫叶矮樱叶片、栅栏组织、海绵组织厚度产生影响,两树种叶片CTR随处理浓度的增加表现为先增加后降低的变化,而SR呈先降低后增加的变化趋势,但两树种变化的幅度不同,在11.4mg.m^-3处理下紫叶李CTR比对照提高4.9%、SR比对照降低6.5%而紫叶矮樱CTR比对照降低了0.9%、SR比对照增加7.6%,22.8mg.m^-3处理紫叶矮樱叶片下表皮几乎全部瓦解,海绵细胞轮廓模糊,而紫叶李叶片的下表皮细胞仅有小部分瓦解。4不同浓度和不同时间SO₂处理对紫叶李和紫叶矮樱叶片活性氧清除系统及有机渗透调节物质均产生影响:细胞伤害指标相关分析表明两树种O₂产生速率、MDA、H₂O₂含量与相对电导率呈显著或极显著正相关,紫叶李相关系数分别为0.531^*、0.784^**、0.572^*,紫叶矮樱相关系数分别为0.663^**、0.912^**、0.609^*;随SO₂处理浓度的增加和处理时间的延长,两树种膜透性和MDA含量均逐渐增加,紫叶李叶片O₂^-产生速率和H₂O₂含量为先降低后升高,而紫叶矮樱逐渐增加;且紫叶矮樱增加幅度大于紫叶李。随SO₂处理浓度增加和处理时间的延长,两树种保护酶SOD、CAT、APX、DHAR、GR、GST、GPX酶活性和抗氧化剂GSH、DHASA、Car、渗透调节物质Pro含量均为先增加后降低的变化趋势,而POD、可溶性蛋白和可溶性糖逐渐增加;两树种GSSG先降低后增加,紫叶李还原型AsA含量呈先增加后降低而紫叶矮樱为逐渐降低的变化。紫叶李膜透性与POD、APX、GST、GSSG、Pro、可溶性蛋白呈极显著相关,紫叶矮樱膜透性与保护酶POD、APX、DHAR、GPX、GST及抗氧化剂ASA、DHASA、GSH、GSSG、CAR和Pro呈显著或极显著相关。5 SO₂处理对紫叶李和紫叶矮樱叶片内源激素含量和种类产生影响:紫叶李和紫叶矮樱叶片内源ABA、IAA、GA、ZT和DHZR含量随SO₂处理浓度的增加或处理时间的延长均呈先增加后逐渐减少的变化趋势。当处理浓度大于等于17.1 mg.m^-3时和处理时间大于等于8d时紫叶李叶片ZR被诱导产生,而紫叶矮樱叶片中未检测到ZR。6 SO₂处理对紫叶李和紫叶矮樱叶片色泽及相关酶产生影响:本研究采用测定色素含量和色差仪测量两种方法对SO₂处理下两树种叶色变化进行度量,SO₂处理使叶片中叶绿素、类胡萝卜素（Car）、花青苷和总酚含量发生变化,从而使两树种叶片的色度值产生变化,随处理浓度的升高紫叶李和紫叶矮樱叶片的L^*、、b^*、C^*均为先增加后降低的变化趋势:紫叶李叶片a^*呈先增加后降低的变化,而紫叶矮樱叶片a^*呈现逐渐降低的变化趋势。色素含量和色度值的相关分析表明,花青苷是决定紫叶李叶片色泽的主要物质,而决定紫叶矮樱叶片色泽的主要物质为花青苷和类胡萝卜素。随SO₂处理浓度的增加和处理时间的延长,紫叶李和紫叶矮樱叶片UFGT酶活性呈先增加后降低的变化;两树种PAL、CHI、PPO酶活性变化不同,紫叶李呈先增加后降低的变化而紫叶矮樱呈逐渐降低的变化趋势;紫叶李PPO、UFGT酶活性在所有处理中均高于紫叶矮樱,而CHI、PAL酶活性低于紫叶矮樱。通过相关分析表明PAL、UFGT、内源激素及可溶性糖含量对叶片色泽均有直接或间接的影响。7 SO₂处理对紫叶李和紫叶矮樱叶片的光合特性产生影响:不同浓度和不同时间的SO₂处理使两树种Pn与Ci变化方向相同且Ls与其变化方向相反,表明SO₂处理下光合速率的下降主要是由于气孔导度的降低引起的。低浓度和短时间的SO₂熏气处理使两树种叶片的Fv/Fm值和F_v/F_o值升高,在高浓度下,叶片的Fv/Fm值和F_v/F_o值都显著降低。随处理浓度的增加和处理时间的延长,紫叶李q_p值降低而q_N值上升,紫叶矮樱叶片q_p和q q_N值均降低。紫叶李可以在保持较高的光合速率和PSⅡ线性电子传递效率的同时,维持一定的光呼吸和热耗散能力,是一种能有效抵御胁迫因子伤害,同时还能兼顾自身生长的主动适应方式。8外源NO处理可以提高紫叶李和紫叶矮樱对SO₂污染的抵抗能力:外源NO通过不同程度的提高植株体内的保护酶活性、抗氧化剂、有机渗透调节物质及内源激素含量清除体内过量自由基,使叶片结构、色泽保持完好,使光合速率和PSⅡ电子传递效率提高,抑制SO₂对两树种的伤害,促进两树种新稍和叶片的生长,提高植株抗性。两树种比较,由于紫叶矮樱伤害较重,外源NO对紫叶矮樱伤害的抑制作用要强于紫叶李。更多还原

【Abstract】 Using two-year-old ported seedlings of Prunus cerasifera Var atropurpurea, Prunus×cistenena ’pissardii’,Prunus wrasifers ’nigra’ and Prunus×bliriana ’Meirenmei’ as materials which cultivated in closed chamber after treated with sulfur dioxide stress,the effects of different conditions on the morphological and Physiological features of seedings were analyzed,which include the sulfur dioxide stress of different concentration,17.1 mg.m^-3sulfur dioxide stress of different time and the sulfur dioxide stress of exogenous NO conditions.The mechanism of colored-leaf species in Prunus adapting to sulfur dioxide stress was clarified preliminarily to provide scientific evaluation of SO₂ resistance and scientific references for selecting proper species as ornamental trees in landscape.The results were as follows.1.The indices including membrane permeability,MDA,proline,soluble proteins,POD, SOD,CAT,pH value and sulfur absorbed content were analyzed with formula of fuzzy mathematics.Synthetical evaluation result of subordinate function analysis suggested that the resistance of four colored-leaf species to sulfur dioxide stress ranked from P.cerasifera var atropupurea,P.wrasifers ’nigra’,P.×bliriana ’Meirenmei,P.×cistenena ’pissardii’.2.The visible injury of P.cerasifera var atropupurea and P.×cistenena ’pissardii’ varied with different SO₂ concentrations.For an instance,under 17.1 mg.m^-3SO₂ treatment, lightly faded spots appeared on abaxial leaf surface edges of P.cerasifera var atropupurea. while obvious faded spots appeared on adaxial and abaxial leaf surface edges of P.×cistenena ’pissardii’,and the abaxial leaf surface were damaged severely.3.The thickness of leaves,palisade tissue and spongy tissue was affected with different concentration of SO₂ treatment,CTR of P.cerasifera var atropupurea and P.×cistenena ’pissardii’ increased first and then dropped with the increment of SO₂ concentration,SR was in an inverse trend,but the changes degree between two species were different.Under SO₂ treatment of 11.4mg.m^-3,CTR of P.cerasifera var atropupurea were increased by 4.9%,and its SR were decreased by 6.5%,while CTR of P.×cistenena ’pissardii’were decreased by 0.9%,and SR were increased by 7.6%compared with the control.SO₂ treatment of 22.8mg.m^-3decreased the CTR of P.cerasifera var atropupurea and P.×cistenena ’pissardii’by 1.3%and 7.4%respectively,and increased the SR of P. cerasifera var atropupurea and P.×cistenena ’pissardii’by 2.5%and 11.0%respectively compared to their controls.Under the SO₂ treatment of 22.8mg.m^-3,the abaxial foliar epidermis in leaves of P.×cistenena ’pissardii’ were almost disintegrated,the outline of spongy cells were not distinct,while the abaxial foliar epidermis in leaves of P.cerasifera vat atropupurea were disintegrated a little.4.Active oxygen scavenging system and organic osmolytes contents were affected under the sulfur dioxide stress of different concentrations and different times:According to correlation analysis,the production rate of superoxide anion radical,MDA and H₂O₂ contents had significant or most significant positive correlation with the relative conductivity,Correlation analysis of P.cerasifera var atropupurea.was 0.531^*,0.784^**,0.572^* and Correlation analysis of P.×cistenena ’pissardii’ was 0.663^**,0.912^**,0.600^*respectively. With the increment of concentration and duration of SO₂ treatment,the membrane permeability and MDA contents of two species increased steadily,while the rising extents in P.×cistenena ’pissardii’ was larger than that in P.cerasifera var atropupurea. O₂^- production rate and H₂O₂ contents in leaves of P.cerasifera var atropupurea increased, and then decreased,while in P.×cistenena ’pissardii’,they all increased with SO₂ treatment concentration and time enhancing.As SO₂ concentration and duration increased,activities of protective enzyme, including SOD,CAT,APX,DHAR,GR,GST,GPX,antioxidant such as GSH,DHASA, Car,and Pro contents of P.cerasifera var atropupurea and P.×cistenena ’pissardii’ increased,and then decreased,while activities of POD,contents of soluble protein and soluble sugar were in an steadily increasing trend.GSSG contents of two species were reduced first and then increased.The deoxidize AsA contents of P.cerasifera var atropupurea increased at first then decreased,while those of P.×cistenena ’pissardii’ decreased gradually.The relative conductivity of P.cerasifera var atropupurea had significant or most significant correlation with the indexes POD,APX,GST and had most significant positive correlation with GSSG,Pro,soluble protein,while the relative conductivity of P.×cistenena ’pissardii’ had significant or most significant correlation with the indexes including protective enzymes POD,APX,DHAR,GPX,GST and antioxidants ASA,DHASA,GSH,GSSG,Car and Pro contents,correlation analysis showed that the damage of cellmebrance of P.×cistenena ’pissardii’was still serious through together function of protective enzymes,antioxidants and organic osmolytes.5.SO₂ treatment affected the contents and kinds of endogenesis hormone.With the increasing of concentration and prolonging of SO₂ treatment,contents of the endogenesis ABA,IAA,GA,ZT and DHZR increased,and then decreased.At the concentration of 17.1 mg.m^-3or higher than that,and the duration longer than 8 d,ZR was induced in P. cerasifera var atropupurea,but no ZR was examined in P.×cistenena ’pissardii’6.The contents of total chlorophyll,carotenoid,flavonoid,anthocyanin and total phenolic were affected in different degree,chroma values of leaf of two species were changed.With the increasing of SO₂ concentration,L^*,b^*,C of leaf of two species increased,and then decreased,a^* of P.cerasifera vat atropupurea Prunus×cistenena ’pissardii’ increased first and decreased later,but a^* of P.×cistenena ’pissardii’decreased gradually.According to the correlation analysis of pigments contents and chroma value,the leaf color of P.cerasifera var atropupurea lied on anthocyanin,while for P.×cistenena ’pissardii’,the leaf color was determined by anthocyanin and carotenoid.UFGT activity in leaves of P.cerasifera var atropupurea and P.×cistenena ’pissardii’increased and then decreased as SO₂ concentration increased and duration prolonged.PAL,CHI,PPO enzyme activities of Prunus cerasifera var atropupurea showed a trend of increasing first and then decreasing,differently,their activities of P.×cistenena ’pissardii’ decreased gradually.According to correlation analysis,activities of PAL,UFGT, the contents of endogenesis and soluble sugar influenced leaf color directly or indirectly.7.With the increasing of concentration and prolonging of SO₂ treatment,the photosynthetic parameters Pn,Tr,Gs,WUE increased first and then decreased,but Ls were in opposition to them.Pn and Ci showed inverse variation trends compared with Ls,SO₂ treatment reduced photosynthetic rates were mainly caused by the decreasing of stomatal conductance（Gs）.Under low concentration and short duration of SO₂ treatment,the values of Fv/Fm and F_v/F_o increased,while their values significantly decreased at thick concentration of SO₂.With the increasing of concentration and duration,for P.cerasifera var atropupurea,q_p decreased and q_N increased,but q_p and q_N of P.×cistenena ’pissardii’decreased.P.cerasifera var atropupurea maintained the definite ability of photorespiration and heat dissipation at the same time holding higher net photosynthetic and PSⅡelectron transport rate,so P.eerasifera var atropupurea had the initiative adaptive mode which resisted damage of stress factors effectively and had self growth simultaneity.8.Exogenous NO could improve the ability of resistance of two species to SO₂ treatment.Exogenous NO could eliminate superoxide anion radical and abirritate of SO₂ damage through improving the activities of protective enzyme,contents of antioxidant, organic osmolytes and endogenesis hormone at different degree,the color and structure of leaf was maintain completely,the systems of photosynthesis and fluorescence was protected,the growth of twigs and leaves of two species was accelerated,the ability of SO₂ tolerance of species was improved.Compared with two species,exogenous NO had more effective resistance of SO₂ damage to P.×cistenena ’pissardii’ because the injury of SO₂ was serious.更多还原