【作者】 张涛；

【导师】 李志华；

【作者基本信息】 南京农业大学 ， 草业科学， 2014， 硕士

【摘要】 为探讨海滨雀稗(Paspalum vaginatum)’Seaspray’结缕草(Zoysia japonica)‘兰引3号’的耐盐机制,为草坪草耐盐育种及绿化生产过程中的抵抗盐分胁迫提供理论依据。本研究采用盆栽试验的方法,研究不同浓度的NaCl溶液(0,100,200,300,400和500 mmol/L)处理对两种草坪草生长特性、生理指标、光合生理的影响,并借助于微根管技术(Minirhizotron)对海滨雀稗和结缕草在盐胁迫下的根系生长到消亡过程中的根系长度、根系表面积、根系投影面积、根系直径、根系体积为基础的根系生长速率进了原位监测,得到以下结论。(1)在NaCl处理下海滨雀稗和结缕草的生长受到一定影响。在盐处理第14d和21d.当NaCl浓度为300、400和500 mmol/L时两种草的相对生长速率、生物量和叶片相对含水量的均显著低于对照。比较500 mmol/L NaCl浓度下3个观测期的值发现,海滨雀稗和结缕草的相对生长速率、生物量均随胁迫时间的延长而明显降低。(2)不同浓度的NaCl处理对海滨雀稗和结缕草生理作用产生影响。在第7d、第14d和第21d三个不同的观测期,随着NaCl农度的增加,海滨雀稗和结缕草相对电导率和渗透调节物质含量均有增加的趋势,NaCL胁迫第14d时,NaCl浓度在400和500 mmol/L的处理时使海滨雀稗和结缕草的相对电导率、丙二醛含量和脯氨酸含量与对照相比均存在明显增加。随着盐处理时间的增加,海滨雀稗和结缕草相对电导率、丙二醛含量和脯氨酸含量均呈现升高的趋势。在盐处理第7d盐浓度小于300 mmol/L盐胁迫程度下海滨雀稗和结缕草SOD活性升高,在高盐浓度(>300 mmol/L)下呈下降的趋势。随着NaCl胁迫程度的增加POD和CAT酶活性逐渐降低。(3)不同浓度盐处理对海滨雀稗和结缕草光合作用的影响,随]NaCl胁迫程度的加剧,海滨雀稗的净光合速率(Pn)在100 mmol/L NaCl浓度处理与对照相比显著增加，其他各处理则随NaCl胁迫程度的增加而逐渐下降；且气孔导度(Gs)和蒸腾速率(Tr)呈逐渐降低的趋势,且500 mmol/L NaCl浓度处理时与对照相比显著降低。海滨雀稗叶片水分利用效率(WUE)和海滨雀稗的气孔限制值随NaCl胁迫程度的增加呈逐渐增加的趋势,且在第7d 400 mmol/L浓度的NaCl容液下比对照显著增加。结缕草的净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)、叶片水分利用效率(WUE)呈逐渐下降的趋势,且在500 mmol/L浓度的NaCl溶液处理与对照相比显著降低；分别在NaCl胁迫第14d和21d时，500 mmol/L NaCl浓度处理与对照相比使结缕草的胞间C02浓度(Ci)和气孔限制值(Ls)明显增加(4)海滨雀稗和结缕草的根系长度均随盐胁迫程度的增加而先升高后降低,在100 mmol/L盐浓度处理时达到最大。根系投影面积和根表面积,海滨雀稗在300mmol/L浓度处理有显著降低,结缕草在100 mmol/L浓度处理有显著降低。盐胁迫刺激了海滨雀稗根系直径的增长,各浓度处理均明显高于对照；结缕草的根系直径受到盐胁迫的抑制,各处理均有不同程度的降低。更多还原

【Abstract】 To explore the seashore paspalum(Paspalum vaginatum)’Seaspray’ zoysiagrass (Zoysia japonica) ’Lanyin NO.3’salt-tolerant mechanism for breeding salt-tolerant turf grass and green manufacturing process provides a theoretical basis to resist salt stress. A pot experiment was conducted to study the different NaCl concentrations (100,200,300,400 and 500mmol/L) treatment on seashore paspalum (Paspalum vaginatum) and Zoysia grass (Zoysia japonica) growth, physiology, photosynthesis and root physiological indicators, and by means of micro-root tube technology (Minirhizotron) on seashore paspalum and zoysia root growth under salt stress to the demise of the process of root length, root surface area, root projected area, root diameter, root volume-based rate of root growth into the in-situ monitoring the following conclusions.(1) Under NaCl treatment the growth of seashore paspalum and zoysia are affected. In the 14d and 21d under salt treatment, at the NaCl concentration of 300, 400 and 500 mmol/L the relative growth rate of two grass biomass and leaf relative water content are significantly lower then the CK. Compare the value under 500 mmol/L of three observations we can find that the relative growth rate and biomass of seashore paspalum and zoysia significantly reduce with stress time extend.(2) Different concentrations of NaCl treatment affect the physiological effects of seashore paspalum and zoysia.At three observation period(7d,14d,21d), with the increasing of NaCl concentration, Zoysia soluble protein content, relative electrical conductivity and MDA had a rising trend meanwhile at 21d under 400 and 500 mmol/L NaCl concentration, relative electrical conductivity, MDA and proline content and soluble protein content had a more significant rising trend than control. Compared the values at three observation period under 500mmol/L respectively, we found that relative growth rate, biomass and leaf relative water content of Zoysia were decreased and relative electrical conductivity, MDA and soluble protein were increased with a greater salt stress. Under high NaCl concentration, POD and CAT enzyme activity were low.(3) Different concentrations of NaCl treatment affect the photosynthesis effects of seashore paspalum and zoysia Pn was higher than control at 100mmol/L NaCl concentration, but other treatments Pn were decreased with NaCl concentration increasing.Gs and Tr were declined at high NaCl concentration and 500mmol/L treatment was significantly lower than control. WUE and Ls were increased with NaCl stress and significantly higher than control under 400mmol/L NaCl concentration at 7d.(4) The results showed that:Seashore Paspalum and Zoysia root length increased with increasing of salt stress at first and then decreased after reaching to the maximum at the 100 mmol/L NaCl concentration. Seashore paspalum root projected area and superficial area were significantly reduced at 300 mmol/L NaCl concentration, at same time Zoysia’s downtrend were began at 100 mmol/L NaCl concentration. Salt stress stimulated Seashore Paspalum root diameter increase and each treatment were significantly higher than the control. Zoysia root diameter were decreased because of salt stress inhibition.更多还原