【作者】 苏忠；

【导师】 李建东； 魏春雁；

【作者基本信息】 东北师范大学 ， 生态学， 2008， 博士

【摘要】 本文通过野外调查和观测、田间试验、温室试验、实验室内理化分析等方法,对松嫩草原罗布麻(Apocynum venetum L.)的有性繁殖特性、无性繁殖特性、耐盐碱特性和化学生态特性等进行了研究,目的在于进一步找出其生物学特性、进一步发掘其资源可利用性、进一步发现其资源开发途径,以对这种具有特殊生态意义的资源性植物的开发利用起到促进作用。在松嫩草原,罗布麻群落斑块状分布在羊草草甸内,罗布麻群落内的伴生植物有羊草等共计31种。罗布麻的有性繁殖特性松嫩草原罗布麻5月末进入蕾期,6月中旬进入初花期,6月下旬进入盛花期,7月中旬进入末花期。整个花期50余天,单个小花的花期为5～7天。7月中旬现果,9月中旬果实成熟,从现果到果实成熟需60天左右。植株总的小花数量与进入初花期的先后时间显著负相关,结实率与小花数量明显负相关。结实率很低,平均仅为0.8%。先期进入花期的罗布麻,果实内所含种子数量较后开花的要低。先后进入花期的罗布麻种子千粒重的差异不大。罗布麻植株一级分枝数平均为每株15.39条,初花期不同的种群一级分枝数在12.72～18.20之间,单株上最少的9条,最多的达23条。但是,分枝数量多,小花数和果实数并不同步增多。随着初花期的延迟,在主茎上和一级分枝上,小花数量均有减少的趋势。主茎上的小花总数与平均数均多于一级分枝上的小花总数和平均数。同步地,主茎上的果实数量多于一级分枝上的果实数量。随着初花时间的延迟,罗布麻主茎与一级分枝的结实率一致表现为增加的趋势,主茎上的结实率远高于一级分枝上的结实率。与一级分枝比较,主茎上的种子更饱满,千粒重更重。种子繁殖容易,播种后三天即出苗,第七天出苗最多,20天出完。出苗率以草甸土最高,达到86%;其次是农田沙壤土,为80%;再次为碱化草甸土,出苗率48%;盐碱土中最低,仅20%。虽然在盐碱土上只有20%的出苗率,仍表明罗布麻具有很强的耐盐碱能力,可以作为盐碱地植被恢复和改良的先锋植物,具有很高的生态价值和经济价值。罗布麻的无性繁殖特性因成活率更高,罗布麻垂直根是无性繁殖更好的取材部位。2cm根段成活率低,不适合作罗布麻无性繁殖材料,而3cm的垂直根根段和5cm的水平根根段是根段繁殖最适宜截取长度。因沙培成活率超过了90%,生殖生长后期截取根段是罗布麻无性繁殖取材的最佳时期。50ppm ABT-1处理生殖生长后期2cm垂直根根段,沙培一个月后的成活率为62.5%,而对照组无成活,表明生根粉溶液显著提高2cm罗布麻垂直根根段成活率。以生根粉处理生殖生长后期的垂直根2cm根段作为无性繁殖材料,是一种更经济的罗布麻繁殖措施。罗布麻茎段扦插生根困难。这一未解课题需要在今后的研究工作中,通过进一步探讨罗布麻自身生理特性和生根粉溶液的浓度来加以解决。罗布麻的耐盐碱特性综合盐碱度8项检测指标,特别是电导率和,将松嫩草原6种来源土壤的盐碱化程度分为三个级别:轻度盐碱化,农田土和退耕地土壤,土壤的电导率均在200us/cm以下;中度盐碱化,碱化草甸土,土壤的电导率309-316us/cm之间;重度盐碱化,盐碱土,土壤电导率在596-956us/cm之间。在盐碱胁迫下,电导率309.00us/cm、pH7.56以下时,盐碱成分的增加可以促进罗布麻的出苗,当电导率超过309.00us/cm、pH7.56时,罗布麻的出苗被逐渐抑制,电导率达到956us/cm、pH9.87时罗布麻种子的出苗受到完全抑制。土壤盐碱含量的升高,明显抑制罗布麻根长和茎长的生长以及根、茎、叶的生物量的增加。在盐碱胁迫下,1610-8010us/cm的高电导率和9以上的高pH值条件下,罗布麻种子在培养箱内能快速近全部萌发,这一结果提示,罗布麻种子繁殖有可能成为生产上可以运用的有效的繁殖方式。但该结果与土壤栽培试验结果有差距,有待进一步验证。盐碱浓度的升高抑制了罗布麻萌发后胚根和胚芽的生长。罗布麻的化学生态特性罗布麻叶中粗蛋白的含量从苗期(21.33%)经花期(盛花期13.25%)到果期(盛果期10.95%)呈现明显下降趋势,表明罗布麻叶在整个生长发育期的饲用质量持续降低。叶中水解氨基酸的含量变化趋势与粗蛋白相同,从苗期到果期呈下降趋势。生长发育不同时期罗布麻叶中粗脂肪的含量变化呈现两个峰值,第一个峰值出现在6月12日的花蕾期,达到了4.51%;第二个峰值达到5.81%,出现在8月14日的盛果期。整个果期罗布麻叶中的脂肪含量都较高,而果后营养期脂肪含量下降,表明果期储备的高量脂肪,可能在果后期转运到果实和种子。除了在花期时出现一个峰值外,罗布麻叶中可溶性糖的消长动态为一个缓慢的下降趋势。在花期出现高峰值,表明可溶性糖与生殖时期的罗布麻的生理关系密切。综合考虑一般营养成分的积累状况,建议作为饲用资源时,罗布麻最佳利用时间应在花蕾期之前。总黄酮在罗布麻花中分布最多,含量达到12.89%,叶中次之(7.21%),茎中再次(1.92%),根和果实中分布很少。因黄酮化合物是罗布麻药用的主要生物活性物质,依据总黄酮含量和生物产量,可确定药用罗布麻的最佳采收部位为叶和花。总黄酮在罗布麻叶积累动态呈现为两峰夹一谷,初花期和果实成熟期为罗布麻叶总黄酮积累高峰期,而盛花期为一个低谷期。提示在旺盛的生殖期,黄酮类化合物可能由叶器官向花器官转移,以供应生殖生理需要。槲皮素的积累动态也与总黄酮一致,呈现为盛花期前后的两峰夹一谷状态。遇到血清时,槲皮素分子结构中的B环和C环、A环和C环形成的两套共轭体系中的电子,发生转移并使酚羟基解离,形成带双负电荷的阴离子,此阴离子将与人血白蛋白结构中结合位点上的氨基酸残基以离子键的形式结合。对人血清白蛋白具有荧光增强的效应。槲皮素与人血白蛋白结合后的相互作用机理、结合位点、结合强度和结合模式的揭示,对深入了解罗布麻活性成分在人体内的运输、分布以及其药理药效具有重要的意义,在药物分子设计方面也具有应用价值。更多还原

【Abstract】 In this thesis,the characters of sexual reproduction,asexual reproduction,saline-alkaline tolerance and chemical ecology of Apocynum venetum L.were studied by such methods as wild investigation,measure,field tests,green-house tests,physical and chemical analysis.The aims of this thesis are to find out the biological characters of A.venetum,excavate resource uses of A.venetum and discover the development ways of A.venetum resource,and to promote the resource to be developed quickly.In Songnen grassland,the distribution of A.venetum in Leymus chinensis meadow was shown in spot pattern.In the community of A.venetum,there were 31 species of plants such as L.chinensis and so on.The characters of sexual reproduction of A.venetumA.venetum comes to flower bud stage in the end of May,to initial bloom stage in the middle ten-days of June,to the full-bloom stage in the last ten-days and to the last bloom stage in the middle ten-days of July.Whole bloom stage of A.venetum spends more than 50 days.The every little flower blooms for 5-7 days.The fruit of A.venetum comes in the middle ten-days of July and is mature in the middle ten-days of Sept.Total little flower number of A.venetum plant was correlated negatively with the time when it came to initial bloom stage. Seed rate was correlated negatively with the little flower number.Seed rate of A.venetum was very low and it was just 0.8%.In the fruit that bloomed early,seed number was less than the one that bloomed late.The differences of 1000-grain weights between A.venetum that bloomed early and that bloomed late were not evident.The mean number of the first branch on one plant of A.venetum was 15.39.The number of the first branch on one plant in different population was 12.72～18.20 in the initial bloom stage and the lest one was 9,the most one was 23.But the numbers of little flower and fruit did not increase with the number of branch.The numbers of little flower on the main stem and first branch all decreased with the delay of initial bloom stage.Total number and mean number of little flower on the main stem are more than those on the first branch.Similar situation occur in fruit.Seeding rate of the main stem and first branch all increased with the delay of initial bloom stage.Seeding rate of main stem was higher than the one of first branch. Comparing with the first branch,the seed of main stem was fullerSexual reproduction of A.venetum is easy.The third day after sowing,plantlet occurred. Plantlet came out in the most amount in the 7^th day.All plantlets had come out in 20^th day. Plantlet rate in meadow soil was 86%.Sandy soil was 80%,alkaline meadow soil 48%and saline-alkaline soil just 20%.Even 20%plantlet rate,it still showed that A.venetum has strong saline-alkaline tolerance and A.venetum could be used pioneer plant when saline-alkaline soil needs to be recovered and meliorated.The characters of asexual reproduction of A.venetumThe segment from vertical root of A.venetum was good asexual reproduction material due to high survival rate.The segment of 2cm was not good reproduction material due to low survival rate.The 3cm segment and 5cm segment were best length for vertical root and horizontal root respectively.The last generation stage was the best time for collection of root segment.The 2cm segments of vertical root were treated by 50ppm ABT-1 and the survival rate of them reached 62.5%after growing in sandy soil for 3 months.It shows that ABT could promote survival rate of 2cm root segment of A.venetum remarkably and it would be good reproduction measure to use 2cm root segment with ABT treatment.Stem segment cutting of A.venetum was difficult.This problem needs to be studied further in future works.The characters of saline-alkaline tolerance of A.venetumThe soil samples from Songnen grassland were graded into 3 levels.The slight saline-alkaline soil insists of farm soil and abandoned cropland and the conductivity of the soil was below 200us/cm.Middle saline-alkaline soil insists of alkaline meadow soil and the conductivity of the soil was between 309-316us/cm.Heavy saline-alkaline soil insists of saline-alkaline soil and the conductivity of the soil was between596-956us/cm.Under the condition of saline-alkaline threatening:when the conductivity of the soil was below 309.00us/cm and pH was below 7.56,the increase saline-alkaline component could promote A.venetum plantlet to come.When the conductivity of the soil was over 309.00us/cm and pH was over 7.56,the increase saline-alkaline component could restrain A.venetum plantlet to come.When the conductivity of the soil reached 956us/cm and pH 9.87, saline-alkaline component restrained A.venetum plantlet to come completely.The increase of saline-alkaline component of soil could restrain growing of root and stem and biomass increase of root,stem and leaf.Under the condition of saline-alkaline threatening:A.venetum seed could germinate in incubator quickly and almost fully when the conductivity of culture solution was 1610-8010us/cm and pH was over 9.The result suggests that seed reproduction could become an effective reproduction model of A.venetum in practical production.But the result needs to be confirmed again due to some difference with the result from culture test in soil.The increase of saline-alkaline concentration restrained growing of radicle and embryo of A.venetumThe characters of chemical ecology of A.venetumThe content of crude protein in the leaf of A.venetum displayed an outstanding degressive trend from seedling period（21.33%）,through blooming flower period（13.25%） and to fruit period（10.95%）.It revealed that the feeding value is to decline continuously during whole growing and developing period.The change trend of contents of hydrolyzed amino acids in leaf of A,venetum was same with that of crude protein.It was degressive from seedling to fruit during whole growing and developing process.The content change of crude fat displayed 2 peaks.The first peak was in the 12th of June and the content reached 4.51%;the second peak was in 14th of Aug and the content was 5.81%.Fat content was high in fruit period and degressive in nutrition period after fruit.It means saved fat in leaf could be transferred to fruit and seed.Except one peak occurred in flower period,the content of soluble sugar in the leaf of A. venetum was a slow degressive tend.The peak means that soluble sugar correlated closely with physiological action of A.venetum during procreant period.As a grazing grass,the best collecting time of A.venetum was suggested in flower bud period according to above study results.In different organs,the highest content,12.89%,of total flavonoid was in flower.The second organ（7.21%） was in leaf and the third（1.92%） in stem.In root and fruit,just a little flavonoid occurred.According to the content and biomass of total flavonoid,leaf and flower of A.venetum were suggested to be the best organs used as natural medicineDynamic accumulation of total flavonoid in leaf of A.veneturn displayed one valley （blooming flower period） lying between two peaks（flower beginning period and fruit maturating period）.It means that flavonoid could be transferred to flower from leaf in order to meet procreation need during procreating period.The accumulation mode of quercetin was same with the mode of total flavonoid.One valley（blooming flower period） lied between two peaks（flower beginning period and fruit maturating period）.When meeting blood serum,the electron on the ring B-C and A-C of quercetin molecule would move and make -OHs of Ring B and A ionizated and one anion with double negative charge would present.The anion would connect with amino acid of white protein in blood serum by ionic band and enhanced fluorescence effect of white protein.The mechanism,point,intensity and model of connection of quercetin and white protein in blood serum have been revealed in this thesis and it would help us to know how effective compounds of A.venetum transfer and distribute in human body deeply and let us to know more knowledge about pharmacological effects of effective compounds of A.venetum.And it also has important value in molecular design of drug.更多还原