【作者】 王龙强；

【导师】 蔺海明；

【作者基本信息】 甘肃农业大学 ， 药用植物资源与利用， 2011， 博士

【摘要】 本文采用野外试验与室内模拟处理相结合的方法,对自然盐渍生境下荒漠盐生药用植物黑果枸杞渗透调节机制、光合作用、叶片超微结构及模拟条件下幼苗生长规律、渗透调节及离子区域化分布等内容进行了深入研究,旨在探讨黑果枸杞耐盐生理生态机制,为引种驯化及种质资源保护提供理论依据。得出的主要结论如下:1.随着植株高度的增加,黑果枸杞叶片肉质化程度增加,丙二醛和脯氨酸含量下降,可溶性糖和可溶性蛋白含量在植株高度20～40 cm时含量最低,在小于20 cm时相对最高,而K⁺/Na⁺、Ca²⁺/Na⁺、Mg²⁺/Na⁺、Si⁴⁺/Na⁺均在30～40 cm时最大,而在10～20 cm时最小。可见,在野生状态下,黑果枸杞在30～40 cm高度时个体耐盐能力最强,而在20 cm以下时耐盐能力最弱。当邻体植物为白刺和柽柳时,黑果枸杞叶片肉质化程度相对较高,丙二醛、脯氨酸、可溶性糖和可溶性蛋白含量也较低,K⁺/Na⁺、Ca²⁺/Na⁺、Mg²⁺/Na⁺和Si⁴⁺/Na⁺则较高,而当邻体植物为花花柴和盐爪爪时,各物质积累情况正好相反。通过综合评价,发现黑果枸杞叶片在邻体植物为白刺时隶属函数值最高,其次为柽柳、盐爪爪,花花柴时最小。说明黑果枸杞在邻体植物为白刺时耐盐能力最强,而邻体植物为盐爪爪或花花柴时耐盐能力较弱。就不同器官而言,Na⁺、K⁺、Cl^-主要分布在黑果枸杞地上部分,而Ca²⁺主要分布在根部,Mg²⁺在叶片中最高,Si⁴⁺则茎中最高;根中K⁺/Na⁺、Ca²⁺/Na⁺均比叶片为高。同时,K⁺/Na⁺、Ca²⁺/Na⁺、Mg²⁺/Na⁺、Si⁴⁺/Na⁺总体呈现随根长增加呈现“两头大,中间小”的变化规律。2.在民勤盐渍区生长的5种荒漠植物黑果枸杞、盐爪爪、白刺、花花柴和芦苇,元素平均含量顺序为Cl>Ca>S>K>Si>Na>P>Mg>Al,其中积盐及泌盐盐生植物中Cl、Ca、S三种元素的相对含量较高,而拒盐盐生植物中K和Si两种元素的相对含量比Ca、Cl和S要高。积盐盐生植物中,黑果枸杞的K/Na、Ca/Na、Mg/Na、Si/Na等离子比值高于盐爪爪和白刺,表现出相对较强的耐盐能力。黑果枸杞及花花柴Fo、qN从早上6:00到18:00呈倒“V”型走势,最大值均出现在中午13:30,而Fm、Fv/Fm、Fv/Fo及Φ_PSⅡ等则呈“V”型走势,最小值出现在13:30。在同一生境中,当环境温度较低时,花花柴热耗散较低,光化学活性比黑果枸杞大,而当环境温度达到全天最高,即接近39～40℃时,黑果枸杞热耗散较高,光化学活性反而比花花柴大,表现出对光抑制较强的适应能力。3.轻度盐胁迫可增加枸杞属两种植物的叶片相对含水量,而随着盐胁迫程度的加重,叶片相对含水量迅速下降,同时,在对照及盐处理组,黑果枸杞叶片相对含水量显著高于宁夏枸杞。盐处理组中黑果枸杞和宁夏枸杞叶片叶绿体各光合色素含量显著高于对照,且随盐浓度升高而增加,但chla/chlb比值在低盐时增加,而后随胁迫程度的加重而快速下降。而叶片相对电导率和各器官丙二醛含量随胁迫浓度的增加而呈逐渐升高趋势,但中、高盐胁迫下,黑果枸杞各器官中的丙二醛含量显著低于同浓度胁迫下的宁夏枸杞。在对照及盐处理组,黑果枸杞和宁夏枸杞脯氨酸和可溶性糖含量在各器官中的分布规律为根>茎>叶。同时,盐处理组中两种植物各器官中的脯氨酸和可溶性糖含量随着盐胁迫浓度的增加呈逐渐增加态势。其中,在对照及盐处理组,黑果枸杞叶片中积累的脯氨酸含量显著高于宁夏枸杞,茎及根中的脯氨酸含量却显著低于宁夏枸杞;在盐胁迫下,两种植物各器官中的Na⁺和Cl^-相对含量均显著高于对照,且随着盐浓度的增加,其含量也逐渐增加,尤以叶片中积累最多;K⁺、Ca²⁺、Mg²⁺、Si⁴⁺在盐处理组各器官中的相对含量比对照降低或无差异。同时,各器官中的K⁺/Na⁺、Ca²⁺/Na⁺、Mg²⁺/Na⁺及Si⁴⁺/Na⁺均随盐浓度增加而呈逐渐下降的趋势。盐处理组中,黑果枸杞各器官中K⁺/Na⁺、Ca²⁺/Na⁺、Mg²⁺/Na⁺和Si⁴⁺/Na⁺离子比值均显著高于同浓度胁迫下的宁夏枸杞,且高盐胁迫下黑果枸杞各离子比值相对于对照下降的幅度远小于宁夏枸杞。综合分析,在盐胁迫下,枸杞属两种植物有机溶质和无机离子同时发生积累,但有机溶质主要在根部积累,而无机离子（主要是Na⁺和Cl^-）则选择在叶片中积累,表现出不同类型渗透调节物在植物渗透调节中的互补性。而且,相对而言,黑果枸杞比宁夏枸杞具有较强的耐盐能力。4.随着胁迫天数的延长,低盐胁迫均可促进黑果枸杞株高、根长、植株鲜干重及根冠比的增加,高盐胁迫虽抑制了黑果枸杞株高生长,降低了叶片、茎及整株的鲜干重,却促进了根长、根鲜干重的增加,并导致根冠比上升;质膜透性和丙二醛含量随胁迫强度和胁迫时间的增加而逐渐增加,且高盐胁迫比在低盐胁迫下,叶片相关指标随时间的积累幅度较大;脯氨酸积累量呈先增加后降低的倒“V”型趋势,与处理前相比,胁迫结束时脯氨酸含量呈几倍甚至几十倍增加,对盐胁迫的响应较为敏感,可溶性糖在低盐胁迫下虽总体呈增加态势,但积累不明显,而高盐胁迫下其含量随胁迫时间增加呈倒“V“型走势,胁迫前后相比其增幅较大;Na⁺和Cl^-相对含量逐渐增加,且高盐胁迫比低盐胁迫积累幅度更大,K⁺、Ca²⁺、Mg²⁺和Si⁴⁺四种离子逐渐下降,且高盐胁迫比低盐胁迫下下降幅度更大,而K⁺/Na⁺、Ca²⁺/Na⁺、Mg²⁺/Na⁺和Si⁴⁺/Na⁺离子比值均呈下降趋势。5.黑果枸杞叶绿体在高盐环境中结构膨大,有部分变成近圆形,淀粉粒消失,空泡化现象非常明显,似空泡状结构呈增多增大趋势,并从叶绿体边缘向类囊体中转移,类囊体结构被破坏。线粒体紧密分布在叶绿体周围,数量不多,变化不大。更多还原

【Abstract】 In order to explore physio-ecological mechanism of salt tolerance of Lycium ruthencium, osmotic regulation, photosynthesis, leaf ultrastructure of natural saline habitat and seedling growth, organic solute, ion content in simulation condition were studied deeply adopting field test and indoor simulation method. These results could provide theoretical basis for cultivation and resource protection of Lycium ruthencium. The main conclusions showed that:1. With height of Lycium ruthenicum increasing, the degree of leaf succulence was improved, but MDA and proline content decreased. Soluble sugar and soluble protein content of plant that height was below 20 centimeters was the higher than that of plant whose height was between 20 to 40 centimeters. The ratio of K⁺/Na⁺, Ca²⁺/Na⁺, Mg²⁺/Na⁺ and Si⁴⁺/Na⁺ were the highest in plant whose height was 30 to 40 centimeters and lowerest in plant that was height of 10 to 20 centimeters. In conclusion, salt tolerance of individuals in the height of 30 to 40 centimeter was the strongest, while the plant whose height was below 20 centimeter was the poorest.When adjacent plant was Nitraria tangutorum and Tamirix, leaves succulent degree of Lycium ruthenicum was relatively higher, but proline, soluble sugar and soluble protein content lower, the ratio of K⁺/Na⁺, Ca²⁺/Na⁺, Mg²⁺/Na⁺, and Si⁴⁺/Na⁺ higher. But when adjacent plant was Karelinia caspica and Kalidium foliatum, each matter accumulation appeared opposite with above situation. Through comprehensive evaluation of subordinate function value, it was found that its value was the highest when adjacent plant was Nitraria tangutorum, successively Kalidium foliatum, Kalidium foliatum and Karelinia caspica. It showed that salt tolerance of Lycium ruthenicum was highest when adjacent plant was Nitraria tangutorum, and lowest when adjacent plant was Karelinia caspica and Kalidium foliatum.As far as different organs were concerned, Na⁺, K⁺ and Cl^- mainly distributed in overground part of Lycium ruthenicum, Ca²⁺ mainly accumulated in its root, but Mg²⁺ and Si⁴⁺ content were highest respectively in leaf and stem. The ratios of K⁺/Na⁺ and Ca²⁺/Na⁺ in root of Lycium ruthenicum were higher than leaf. And the same time, the change laws of K⁺/Na⁺, Ca²⁺/Na⁺, Mg²⁺/Na⁺, and Si⁴⁺/Na⁺ ratios appeared firstly reducing then adding with root length increasing.2. In Minqin saline area, the order of element content of five desert plants such as Lycium ruthenicum, Kalidium foliatum, Nitraria tangutorum, Karelinia caspica and Phragmites australis was chlorine>calcium>sulfur>potassium>silicon>sodium> phosphorus>magnesium>aluminum. Chlorine, calcium and sulfur element content of salt accumulating and excreting plants was relatively higher, while potassium and silicon element of salt excluding plants was higher than chlorine, calcium and sulfur. Among three salt accumulating plants, the ratios of K/Na, Ca/Na, Mg/Na and Si/Na of Lycium ruthenicum were higher than Kalidium foliatum and Nitraria tangutorum, which showed stronger ability of salt tolerance.Fo and qN of Lycium ruthenicum and Karelinia caspica appeared reverse“V”-type tendency from A.M. 6 o’clock to P.M. 18 o’clock, and their maximum value occurred at noon 13:30. While Fm, Fv/Fm, Fv/Fo andΦ_PSⅡ appeared“V”-type tendency, and their minimum value occurred 13:00. In the same habitat, when environment temperature was lower, heat dissipation of Karelinia caspica was lower, its photochemical activity was higher than Lycium ruthenicum. When environment temperature reached the highest, namely close to 39 to 40 centigrade, heat dissipation of Lycium ruthenicum was higher, and its photochemical activity was higher than Karelinia caspica, which showed stronger adapting ability to photoinhibition.3. Slight salt stress could increase relative water content in the leaves of Lycium ruthenicum and Lycium barbarum. But their relative water content declined rapidly with salt concentration increasing. At the same time, relative water content of Lycium ruthenicum was significantly higher than Lycium barbarum in contrast and salt treatment groups. Photosynthetic pigment contents of two plants in salt treatment groups were higher than in contrast, and their contents added with salt concentration increasing. But the ratio of chla and chlb increased in lower salt stress, and then decreased rapidly with stress degree aggravating. Also relative conductivity and MDA content of different organs of two plants increased with salt stress concentration rising, but in medium and high salt stress, MDA content of different organs of Lycium ruthenicum was lower than Lycium barbarum under same salt concentration.In contrast and salt treatment groups, the distribution law of proline and soluble sugar content of two plants was root>stem>leaf. Meanwhile, proline and soluble sugar content of two plants in salt treatment groups added with the increasing of salt stress concentration. Proline content in the leaves of Lycium ruthenicum was higher than Lycium barbarum, but its contents in stem and root of Lycium ruthenicum were significantly lower than Lycium barbarum. There were higher Na⁺ and Cl^- relative content of two seedlings than those of contrast, and its content became gradually higher with salt concentration increasing. Among different organs, accumulation of Na⁺ and Cl^- were the most highest in leaves tissue. On the contrary, K⁺、Ca²⁺、Mg²⁺ and Si⁴⁺ content of seedlings under different salt tolerance reduced or did not vary compared with contrast. At the same time, the K⁺/Na⁺, Ca²⁺/Na⁺, Mg²⁺/Na⁺ and Si⁴⁺/Na⁺ ratios in leaves, stems and roots decreased gradually with salt concentration increasing under NaCl stress. The K⁺/Na⁺, Ca²⁺/Na⁺, Mg²⁺/Na⁺ and Si⁴⁺/Na⁺ ratios in Lycium ruthenicum under salt stress were markedly higher than those in Lycium barbarum, and the descendant degree of these ratios of Lycium ruthenicum were enormously lower than those of Lycium barbarum especially in higher salt concentration.Through comprehensive analysis, it could be found that organic solute and inorganic ions accumulated simultaneously in the organs of Lycium ruthenicum and Lycium barbarum. Differently, organic solute mainly accumulated in roots, but inorganic ions accumulated mainly accumulated in leaves, which showed complementary among different types of osmotic regulation substance. And comparatively speaking, Lycium ruthenicum had stronger ability than Lycium barbarum in salt tolerance. 4. With the extension of stress days, lower salt stress could increase height, root length, fresh dry weight and root/shoot ratio of Lycium ruthenicum. Though higher salt stress suppressed height growth of Lycium ruthenicum, and reduced fresh dry weight of leaves, stems and whole plants, it increased length, fresh dry weight of root and root/shoot ratio. Membrane permeability and MDA content of Lycium ruthenicum increased gradually with stress strength and time increasing, and the accumulation of above two physiological indexes in higher salt stress was larger than lower salt stress with stress time increasing. The accumulation of proline of Lycium ruthenicum firstly increased then decreased during salt stress, but its accumulation at the end of salt stress increased several or even dozens of times compared with stress before, which showed proline was more sensitive to salt stress. Soluble sugar content of Lycium ruthenicum increased in lower salt stress on the whole, but its accumulation was not obvious. Under higher salt stress, soluble sugar content appeared reverse“V”-type tendency with salt stress time increasing, its accumulation at the end of salt stress were bigger compare with stress before. Na⁺ and Cl^- relative content added gradually with salt stress time increasing, and their accumulation in higher salt stress were higher than in lower salt stress. K⁺, Ca²⁺, Mg²⁺ and Si⁴⁺ relative content decreased gradually, and their declining account in higher salt stress were bigger than in lower salt stress. The ratio of K⁺/Na⁺, Ca²⁺/Na⁺, Mg²⁺/Na⁺ and Si⁴⁺/Na⁺ appeared declining tendency with salt stress time increasing.5. Chloroplasts of Lycium ruthenicum became swollen under higher salt environment, even a part of chloroplasts became suborbicular, and starch grains disappeared. Also vacuolated phenomenon was very obvious, the number of like vacuolated structure increased and size largened. These vacuolated structures transferred from edge to thylakoid, which led to thylakoid structure being destroyed. Mitochondria distributed closely around the chloroplast, and its number were a little, the change was not obvious.更多还原