【作者】 赵勐；

【导师】 范海； 赵可夫；

【作者基本信息】 山东师范大学 ， 植物学， 2008， 硕士

【摘要】 据联合国教科文组织（UNESCO）和粮农组织（FAO）不完全统计,全世界盐渍土面积为9.5438亿公顷。根据王遵亲等1993年报道,我国现代（活性）盐渍化土壤的面积总额为5.54亿亩,残余盐渍化土壤约为6.73亿亩,潜在盐渍化土壤为2.6亿亩左右。除此,由于不合理的农业灌溉措施还不断造成一些次生盐渍化土壤,使中国盐碱土面积不断增加,严重地影响我国农作物产量和农业的发展。由于盐碱土对农作物生长的影响,随着盐渍化的日趋严重,阻碍了世界可耕地的利用。因此引起了全世界很多科学家对盐碱地的重视。植物的耐盐问题,主要是指植物对NaCl的耐性问题,植物耐盐生理的研究,主要从两个方面入手:一是研究盐生植物对盐度的耐性生理;二是研究盐度对非盐生植物的盐害生理,从而了解改善和提高植物抗盐能力。因此,本研究从不同盐类对盐生植物和非盐生植物生长和离子分布的影响入手,以盐生植物盐地碱蓬（Suaeda Salsa）和非盐生植物烟草（Nicotiana tabacum L. Var NC82）为实验材料进行了三种盐类对Na⁺和Cl-吸收、运输、积累以及其功能的研究。1.盐地碱蓬:盐生植物盐地碱蓬（Suaeda Salsa）的幼苗分别用0、50、100和200 mmol/L的NaCl、NaNO₃和KCl处理15和30d后取样并测定干鲜重、肉质化、离子含量、SOD活性、光合和叶绿素荧光以及X-ray微区分析的情况。结果显示:（1）. NaCl处理后植株鲜重和干重均随着NaCl浓度的增大而升高,NaNO₃的效应次之,KCl则起抑制作用;（2）.三种盐处理后植株肉质化水平依次为NaCl>NaNO₃>KCl;（3）.离子含量:Na⁺含量依次为NaCl>NaNO₃>KCl,Na⁺含量随着处理时间的延长而增大;K+含量依次为KCl>NaCl>NaNO₃,并且与处理时间和浓度有关;Cl-含量依序为KCl>NaCl>NaNO₃,并随着处理时间的延长而下降;（4）. NaCl促进了碱蓬的SOD活性,而KCl抑制了活性,NaNO₃对SOD的影响不明显;（5）.三种盐对光合的影响情况也不同,NaCl促进了Pn和Gs,KCl处理刚好相反;（6）. NaCl和NaNO₃处理对Fv/Fm的效应不明显,而对ΦPSⅡ则起明显的促进效应。KCl对Fv/Fm和ΦPSⅡ都起明显的抑制作用;（7）.叶细胞各区室内液泡中三种离子相对含量最大;（8）.盐地碱蓬对NaCl的响应特别显著并具有很强的依赖性,200 mmol/L NaCl处理30d后植物体内Na⁺和Cl-含量分别占干重的13.5%和10.1%。显然,盐地碱蓬是一种专性盐生植物,是一种Na和Cl的超富集植物。2.烟草:烟草（Nicotiana tabacum L. Var NC82）在4叶期分别用含有不同浓度NaCl、NaNO₃和KCl的Hoagland营养溶液处理。结果显示:（1）.烟草幼苗鲜重和干重受到不同程度的抑制作用,25 mmol/L NaCl处理的烟草幼苗的鲜重和干重接近对照,NaNO₃和KCl也对烟草幼苗产生不同程度的抑制,而NaCl的抑制作用最大;（2）. NaCl、NaNO₃和KCl对烟草离子积累效应如下: Na⁺积累水平是NaCl>NaNO₃>KCl;K+积累水平被KCl促进,而NaCl和NaNO₃抑制K+的积累;Cl-的积累水平是KCl>NaCl>NaNO₃;NO₃-的积累水平为NaNO₃促进,受KCl抑制,而NaCl作用不明显;（3）.三种盐对SOD活性的抑制是NaCl>KCl >NaNO₃;（4）. NaCl、NaNO₃和KCl的各种浓度也抑制光合作用过程,Pn和Gs被这三种盐抑制,并引起Ci升高;（5）.另外,三种盐也抑制最大PSⅡ效率Fv/Fm和实际PSⅡ光化学效率ΦPSⅡ;（6）.在所有的细胞器中,K含量最高。除液泡外的其它三个细胞器中都是NaCl处理的Na⁺含量最高,Cl-情况为NaCl>KCl。而液泡中离子含量为NaNO₃处理下Na⁺含量最高,在Cl-积累方面是KCl>NaCl。通过上述研究可以看出盐生植物盐地碱蓬对盐的响应特别显著,并且有很强的依赖性;而烟草则相反,它对盐度非常敏感,在25 mmol/L NaCl条件下,其生长即被抑制。说明盐生植物与非盐生植物对盐度的响应有本质的区别。要彻底了解植物的耐盐本质还需要进一步从植物耐盐基因生物学来解决。更多还原

【Abstract】 According to United Nations Educational, Scientific and Cultural Organization （UNESCO） and the Food and Agriculture Organization （FAO） to incomplete statistics, the area of world saline soil is 0.95438 billion hectares. According to the report of Wang et. al.（1993）, the area of Chinese total modern （activity） salinized soil is 0.554 billion acres, together with about 0.673 billion acres of residual salinized soil.Furthermore, there is about 0.26 billion acres of potential salinized soil. Beside these, due to the irrational agricultural irrigation measures, some secondary salinized soil continually appears which increases the area of the Chinese salinized soil, seriously influences Chinese agricultural production and the development of the Chinese agriculture. Due to the influence of the salinized soil to the growth of the crops and the increase of soil salinization, the utilizeation of cultivable land is seriously limited. That aroused the recognition for the salinized soil of many scientists all over the world. The problem of plant’s tolerance to salt is mainly the tolerance to NaCl. The research is mainly focused on two aspects: First, the study of salt-tolerance physiology in halophytes; second, the study of the injurious physiology in nonhalophytes. Thereby we can understand how to ameliorate or increase the plants’salt-resistance. Thus, my study focused on research of the effect of different salts on absorption, transport, accumulation, and the function in halophyte Suaeda Salsa and nonhalophyte Nicotiana tabacum L.1. Suaeda SalsaSeedlings of Chenopodiaceae halophyte Suaeda Salsa were treated with 0, 50, 100, and 200 mmol/L NaCl, KCl and NaNO₃ respectively after germination. The fresh and dry weight, succulent level and ion content were then determined after treated for 15 and 30d. The results showed that: （1）. The fresh and dry weight was promoted by NaCl and NaNO₃ at all concentrations, while inhibited by KCl; （2）. The order of the succulent level under the three salt treatment was NaCl>NaNO₃>KCl; （3）. The order of ion accumulation of Na⁺ was NaCl>NaNO₃>KCl, and Na⁺ content increased with the time course; The order of K+ was KCl>NaCl>NaNO₃, and the content varied with treatment time and concentration; The order of Cl- was KCl>NaCl>NaNO₃, and the content decreased with the time; （4）. NaCl promoted the SOD activity of Suaeda Salsa, KCl inhibited it, while NaNO₃ had no obvious effect; （5）. The effect of the three salts on the photosynthesis was different, NaCl promoted the Pn and Gs, while KCl was opposite to the NaCl treatment; （6）. The effect of NaCl and NaNO₃ on Fv/Fm was not obvious, while they promotedΦPSⅡ. On the other hand, KCl obviously inhibited both Fv/Fm andΦPSⅡ; （7）. The CPS of the three ions in the vacuole was the most in the compartments of leaf cells; （8）. The response of Suaeda Salsa to NaCl was extremely significant and the Na⁺ and Cl- contents in Suaeda Salsa under 200 mmol/L NaCl after 30d were 13.5% and 10.1% respectively. It is obvious that S.salsa is an obligatory sodium and chloride hyperaccumulating halophyte.2. Nicotiana tabacum L.Seedlings of tobacco （Nicotiana tabacum L. var. NC82） at four-leaf stage were treated with Hoagland solution containing different concentrations of NaCl, NaNO₃ and KCl respectively. Results showed that: （1）. The fresh and dry weights of tobacco seedlings treated with NaCl suffered different degree of inhibition, the fresh and dry weights of the seedlings treated with 25 mmol/L NaCl were close to the controls. NaNO₃ and KCl also exerted different degree of stress to tobacco seedlings. The inhibition of NaCl was the biggest; （2）. The effect of NaCl, NaNO₃ and KCl on ions accumulation of tobacco seedlings were as follows: Na accumulation levels were NaCl>NaNO₃>KCl; K+ accumulation levels were promoted by KCl, but K+ accumulation was inhibited by NaCl and NaNO₃; Cl- accumulation levels were KCl>NaCl>NaNO₃; NO₃- accumulation levels were promoted by NaNO₃, but KCl inhibited it, NaCl effects was not obvious; （3）. The initiative effects of NaCl, NaNO₃ and KCl on antioxidase SOD were NaCl>KCl>NaNO₃; （4）. Concentrations of NaCl, NaNO₃ and KCl also inhibited photosynthetic processes. Pn and Gs of tobacco were inhibited by NaCl, NaNO₃ and KCl, while promoted the Ci; （5）. On the other hand, the three salts also inhibited the maximum PSⅡefficiency Fv/Fm and actual PSⅡphotochemical efficiencyΦPSⅡ; （6）. The CPS of K+ in all the cell compartments was the largest. The CPS of Na⁺ in the NaCl treatment was the largest in all the cell compartments except the vacuole, As for the CPS of Cl- in the 3 organelles except vacuole, thr order was NaCl>KCl. On the other hand, the CPS of Na⁺ in the NaNO₃ treatment in the vacuole was largest, while the Cl- was KCl>NaCl.Through the studies above, the response of Suaeda Salsa to NaCl was extremely significant and showed strong dependence, while the tobacco was opposite; it was sensitive to salinty. Its growth was inhibited under the 25 mmol/L NaCl condition. That indicated there was essential difference between the response of halophyte and nonhalophyte to salinty. They are determined by the availability of salt-tolerant gene. To fathome the essences of plant’s salt-tolerance needs further study from the point of plant salt-tolerance genetic biology.更多还原