Response of radial growth to climate change for Larix olgensis along an altitudinal gradient on the eastern slope of Changbai Mountain,Northeast China

AimsTo further understand the sensitivity of tree growth to climate change and its variation with altitude, particularly the growth-climate relationship near the timberline, the radial growth of Larix olgensis in an oldgrowth forest along an altitudinal gradient on the eastern slope of Changbai Mountain was investigated. MethodsThe relationships between climate factors and tree-ring index were determined using bootstrapped response functions analysis with the software DENDROCLIM2002. Redundancy analysis, a multivariate “direct” gradient analysis, and its ordination axes were constrained to represent linear combinations with meteorological elements. The analysis was used to clarify the relationship between tree-ring width indexes at different elevations and climate factors during the period 1959-2009.Important findings indicated: (1) Tree ring chronologies from high altitudes were more superior than other samples in terms of growth-climate relationship, revealing that trees at high altitudes are more sensitive to climate variation than at low sites, (2) Tree growth was mainly affected by temperatures of from before and through growing season in previous year, especially in June and August. In comparison, tree growth in the low elevation was regulated by the combination of precipitation of August and Palmer drought severity index (PDSI) of September in current year, (3) Trees growing below timberline appeared to be more sensitive to climate warming; small extents of habitat heterogeneity or disturbance events beyond timberline may have masked the response, hence the optimal sites for examining growth trends as a function of climate variation are considered to be just below timberline, and (4) Redundancy analysis between the three chronologies and climate factors showed the same results as that of the correlation analysis and response function analysis, and this is in support of previous conclusion that redundancy analysis is also effective in quantifying the relationship between tree-ring indexes and climate factors.     

黄花蒿培养细胞中青蒿素合成代谢的体外调节

黄花蒿培养细胞通过两步培养积累青蒿素．第１步在含有０．２～０．４ｍｇ／Ｌ６－苄基氨基嘌呤（６－ＢＡ）和３～４ｍｇ／Ｌ吲哚乙酸（ＩＡＡ）的Ｎ６培养基中进行细胞的增殖培养,第２步将培养好的细胞转入含０．２～０．４ｍｇ／Ｌ６－ＢＡ和０．２～０．４ｍｇ／ＬＩＡＡ的改良Ｎ６培养基中进行青蒿素的合成．青蒿素的合成量为１９０μｇ／ｇ干细胞左右．当在第２步培养中加入青蒿素合成前体青蒿酸,青蒿素合成量比仅靠激素诱导提高了３倍多．青蒿素的合成途径是植物固醇合成途径的分支途径,当在青蒿素合成过程即第２步培养中加入固醇生物合成抑制剂双氯苯咪唑和氯化氯胆碱处理,可使代谢向合成青蒿素的方向移动,青蒿素合成量明显提高．经２００ｍｇ／Ｌ氯化氯胆碱处理２ｄ,黄花蒿细胞合成青蒿素量为３７２μｇ／ｇ干细胞;经２０ｍｇ／Ｌ双氯苯咪唑处理４ｄ,黄花蒿细胞合成青蒿素量为１５４０μｇ／ｇ干细胞,比靠激素诱导提高了８倍多,与诱导脱分化细胞的黄花蒿叶中所含的青蒿素（３０００μｇ／ｇ干细胞）处于同一个数量级．以上结果表明：在通过植物激素调节可以合成青蒿素的黄花蒿培养细胞中,缺乏青蒿素合成前体是青蒿素合成量低的重要原因．因此,在青蒿素合成的过程中通过体外调节,     

黄花远志的新齐墩时烷型三萜皂甙

从云南产远志科药用植物黄花远志茎皮的乙醇提取物中何妨以４个新的齐墩果烷型三萜皂甙,人花远志皂甙Ａ－Ｄ。同时还分离得到１个已知的三萜皂甙远志甙ＸＸＸＶ。它们的结构通过波谱方法推定。     

不同土壤环境对黄花蒿生长和青蒿素含量的影响研究

通过田间小区试验,比较研究了施肥与不施肥条件下,4种土壤环境（沙土、旱地土、水稻土和棕色石灰土）对黄花蒿的生长、生物量分配和青蒿素含量的影响。结果表明：黄花蒿对土壤养分的适应性较强,在沙土、旱地土、水稻土和石灰土上均能生长发育,养分水平低时,分配更多的生物量到根,根生物量分数和根/冠比增大;养分水平高时,分配更多的生物量到叶,叶生物量分数增加。黄花蒿的生长和青蒿素含量显著受土壤养分的影响,不施肥时,石灰土和水稻土栽培黄花蒿的株高、地径、总生物量、叶生物量和青蒿素含量显著大于旱地土,而旱地土又显著大于沙土。但在施肥条件下,以上参数不同土壤间无显著差异,且显著高于不施肥。因此,只要根据土壤养分状况合理施肥,黄花蒿在不同养分土壤栽培均能获得较高的青蒿素产量。     

黄花石蒜中的黄酮类成分

通过对黄花石蒜（Lycoris aurea）乙醇提取物的乙酸乙酯溶解部分进行分离纯化,得到7个化合物.经物理方法和波谱分析,分别鉴定为（2S）-4＇-羟基-7-甲氧基黄烷（1）、（2S）-3＇,7-二羟基-4＇-甲氧基黄烷（2）、（2S）-4＇,7-二羟基黄烷（3）、（2S）-4＇,7-二羟基-8-甲基黄烷（4）、（2S）-4＇,7-二羟基-3＇-甲氧基-8-甲基黄烷（5）、（2S）-4＇,5,7-三羟基-8-甲基黄烷酮（6）、2,4＇-二羟基-4-甲氧基二氢查尔酮（7）.所有化合物均为首次从该属植物中分离得到,另外,本文首次归属了化合物5、6、7的13C NMR信号.     

黄花水龙作为人工浮岛植物的开发研究

介绍了当前湖泊水环境保护与治理中流行的人工浮岛技术,指出了其面临的等问题。通过野外考察发现,利用一种土著的水生植物黄花水龙作为人工浮岛植物,能够克服当前人工浮岛技术面临的养分溢流,二次污染及生物入侵等若干问题。描述了黄花水龙形态学及生态学特征,并在室内实验的基础上,初步分析了该种植物对污水的净化效果。旨在为人工浮岛的改良与应用提出一条具有实践意义的技术途径,并为湿地水环境生态修复理论研究积累相关的资料。     

尾叶远志抗氧化活性研究

采自贵州兴义的尾叶远志(Polygala caudata Rehd.et Wils.)根,经乙醇提取,再用不同溶剂萃取和柱层析分离,得到了12个不同的组分.用比色法研究了各组分还原三价铁离子及清除脂性自由基DPPH能力,采用化学发光法观察各组分清除羟自由基和超氧阴离子的活性.研究发现,尾叶远志各组分均有一定的清除自由基作用,并且其活性成分可能主要集中在PC-BuOH组分.     

黄花石蒜的组织培养和植株再生

1植物名称黄花石蒜(LycorisaureaHerb.),又名忽地笑。2材料类别鳞茎。3培养条件(1)不定芽诱导培养基:MS+6-BA10mg·L-1(单位下同)+NAA0.5;(2)不定芽增殖培养基:MS+6-BA5+NAA0.5;(3)生根培养基:MS+IBA2。上述培养基均加入3%蔗糖和0.8%琼脂,培养基灭菌前pH5.8。培养温度为19￣21℃,光照时间为12h·d-1,光强为24￣30μmol·m-2·s-1。4生长与分化情况4.1不定芽的诱导将鳞茎用自来水洗净,剥去外层黑色鳞片,切去石蒜的根部和鳞茎的上半部分。将切留的鳞茎放进烧杯置于超净工作台中,先用70%酒精灭菌40￣50s,无菌水冲洗2遍,再用0.15%升汞…     

黄花杓兰根内的小型菌核

Most fungal species Chaetomhun aureum Chivers and Papulaspora byssina Hosson are associated with Cypripedium flavum Hunt et Sumrmnerh. They are confined to Xianggehla County of Yunnan alpine areas, 3 400 - 3 600 m. alt. Bubils of the genus Papulaspora (anamorph) are seem as produced by apothecial fungus as Chaetomium (teleomorph)for those fungi.It is interesting to speculate as to a possible perfact state for those fungi.