2种藏茵陈类植物的引种地繁殖系统研究

通过观察、套袋、人工授粉对引种至低海拔栽培地的2种“藏茵陈”类植物——川西獐牙菜（Swertia mus-sotii）和抱茎獐牙菜（S.franchetiana）繁育系统进行研究.结果表明：（1）引种的2种植物均为雌雄同株、自交亲和,但大部分花雌雄异熟（dichogamy）和雌雄异位（herkogamy）,雌雄同熟的比例为24%,且雌雄同熟的雄蕊群远离雌蕊,需要靠传粉昆虫等传粉媒介传粉.（2）引种到低海拔的2种“藏茵陈”类植物结实率和发芽率均较高,其中川西獐牙菜柱头张开第2天的授粉结实率达76.54%,种子发芽率达84.29%.（3）低海拔栽培的川西獐牙菜的传粉昆虫是家养蜜蜂,抱茎獐牙菜的开花时间较川西獐牙菜晚20 d,有效的传粉昆虫由家养蜜蜂变成一种很小的蜂类.研究表明,川西獐牙菜和抱茎獐牙菜由高海拔引种到低海拔地区后,结实率和种子发芽率均较高,可以用引种栽培的方式进行“藏茵陈”药材的繁殖.

藏药抱茎獐牙菜的引种栽培研究

抱茎獐牙菜Swertia franchetiana H．Snath为龙胆科獐牙菜属植物，主要分布于我国青海、西藏、四川及甘肃南部等地。以全草人药，是治疗黄疸型肝胆疾病和病毒性肝炎的常用藏药之一，藏译音名“蒂达”，俗称“藏茵陈”。近10多年来，随着我国民族医药的迅速发展，抱茎獐牙菜的资源需求快速增加，特别是在植物生长阶段的花果期大量采收导致其资源量锐减和逐渐枯竭，其地域分布亦日益狭窄，野生资源植物濒临灭绝。因此，对抱茎獐牙菜植物人工引种栽培的研究具有十分重要的意义。在国家中西部专项基金的资助下，作者通过3年的技术攻关，初步掌握了抱茎獐牙菜的生长发育特点及引种栽培技术。

二叶獐牙菜化学成分研究

从二叶獐牙菜(Swertia bifolia Batal.)的全草中分离得到了7个化合物,5种口山酮和2种甾醇类化合物.它们的结构经光谱方法分别鉴定为1-羟基-3,5-二甲氧基口山酮(Ⅰ)、1-羟基-3,7,8-三甲氧基口山酮(Ⅱ)、1,8-二羟基-3,5-二甲氧基口山酮(Ⅲ)、1,8-二羟基-3,7-二甲氧基口山酮(Ⅳ)、1,7-二羟基-3,8-二甲氧基口山酮(Ⅴ)、β-谷甾醇(Ⅵ)、胡萝卜苷(Ⅶ).

青藏高原特有植物祁连獐牙菜（龙胆科）的花综合征与虫媒传粉

雌雄异熟和异型花在一些被子植物中的共同存在被认为是一种有效避免两性花植物自交并促进异交的机制。本文报道青藏高原特有植物祁连獐牙菜Swertia przewalskii pissjauk.的花同时具有雌雄异熟和异型花这两种特征。在此基础上，我们详细观察了该植物访花昆虫的访花行为，主要探讨这种促进异花传粉的机制是否能完全避免株内异花传粉的自交。繁育系统试验证明祁连獐牙菜单花套袋不结实，说明雌雄异熟和异型花的花特征完全避免了单花的自花传粉，自然结实必须依赖昆虫传粉才能完成。然而，该植物却是高度自交亲和的，因为人工株内异花自交具有较高的种子结实率。每个植株在盛花期开放1-6朵，平均具有3朵开放的雄性期或者雌性期的花，二者的比例为2：1，在植株上的分布没有规律。我们观察到多种昆虫访问该植物的花，其中，克什米尔熊蜂Bumbuskeshimirensis Friese和蜜蜂如Apis mellifera L．是该植物最常见与最有效的传粉者。进一步的观察发现，这两类传粉昆虫对雌性阶段和雄性阶段的花的访问没有选择，但在一个植株上访花顺序的总体趋势是由下向上的。它们在同一植株上访花数超过1朵的访问比例约占37．1％。因此可以初步推断，祁连獐牙菜中异型花和雌雄异熟现象的共同存在并没有完全避免同株异花传粉导致的自交。结果支持两性花中的这种雌雄异熟和异型花现象可能在避免两性冲突上具有更为重要的功能。

祁连獐牙菜化学成分研究

目的 研究祁连獐牙菜Swertia przewalskii全草的化学成分。方法 采用硅胶柱层析进行分离纯化，通过波谱方法及化学关联进行结构鉴定；结果 分离纯化出15个化合物，分别鉴定为：1，7-二羟基-3，8-二甲氧基San酮（Ⅰ），1，8-二羟基-3，7-二甲氧基San酮（Ⅱ），1，7，8-三羟基-3-甲氧基San酮（Ⅲ），1，3，7，8-四羟基San酮（Ⅳ），1-O-β-D-吡喃葡萄糖基-7-羟基-3，8-二甲氧基San酮（Ⅴ），1-O-β-D-吡喃葡萄糖基-8-羟基-3，7-二甲氧基San酮（Ⅵ），7-O-β-D-吡喃葡萄糖基-1，8-二羟基-3-甲氧基San酮（Ⅶ），1-O-[β-D-吡喃木糖（1→6)-β-D-吡喃葡萄糖]-7-羟基-3，8-二甲氧基San酮（Ⅷ），1-O-[β-D-吡喃葡萄糖]-1，7-二羟基-3-甲氧基S sgmk(X),木犀草素（Ⅺ），齐墩果酸（Ⅻ），乌苏酸（XⅣ）和龙胆苦苷（XV）。结论 化合物Ⅳ-Ⅷ，Ⅺ,Ⅻ,XⅣ和XV均为首次从该种植物中分得。

獐牙菜属植物花蜜腺形态及解剖学

在扫描电镜下观察了獐牙菜属Swertia L.10组30种植物花蜜腺的数目，位置，形态和附属物等特征；同时还利用光镜对各组代表种的蜜腺结构进行了解剖学观察。结果表明獐牙菜属花蜜腺外部形态多种多,但在组与组之间无明显间断，演化序列呈梯度变化；内部结构基本相同，为不具维管束的结构蜜腺，且均为淀粉型蜜腺。因此，从花蜜腺的角度不支持将獐牙菜属划分为小属的观点，同时，还结合其它证据讨论了花蜜腺特征的演化趋势。

四数獐牙菜的胚胎学及其系统学意义（英文）

四数獐牙菜花药四室，药壁发育为双子叶型；绒毡层腺质型。小孢子母细胞减数分裂为同时型，四分体的排列方式为四面体形；成熟花粉为３细胞。子房２心皮，２心皮连接处强烈内凸，４列胚珠。薄珠心，单珠被，直生胚珠。胚囊发育为蓼型。胚乳发育为核型。胚胎发育为茄型酸浆Ⅰ变型。反足细胞在胚囊成熟时期宿存。果实成熟时，种子只发育至球型胚阶段。承珠盘存在。与已研究的獐牙菜种类的胚胎特征相比较，该种存在三个显著的特点：直生胚珠，心皮连接处强烈内凸，承珠盘存在。这三个特征目前仅在龙胆族中的花锚属中发现。经过性状分析，它们均是演征，此三个共有演征表明四数獐牙菜与花锚属是一单系群，它们的亲缘关系最近。这与Yun&Kupfer(1995)的分子证据部分吻合，因为分子系统树上的花锚单系支包括花锚、四数獐牙菜和北美的密花属（广义獐牙菜属中的密花组），而后者的胚胎学特征未有任何报道。胚胎学研究暗示四数獐牙菜的分类学等级有待重新评价，广义的獐牙菜属有可能不是一单系发生群。

A preliminary analysis of the phylogeny of the Swertiinae (Gentianaceae) based on ITS data

To better understand the floral diversity and the phylogeny of the Swertiinae (Gentianaceae), the internal transcribed spacer (ITS) region of nrDNA for 17 species and one outgroup was sequenced. Our data suggest that corolla type, gland shape, and corolla appendage are poorly correlated with the ITS phylogeny. The genus Swertia s.l. and the rotate group previously recognized based on the corolla types and gland shapes are polyphyletic. Four genera with simple protruding glands and three taxa with corolla appendages are not clustered as the monophyletic groups. Four separate clades, corresponding to the four sections, were identified in Swertia s.1. Lomatogoniopsis with the simple protruding gland type of the tubular group closely related to Lomatogonium of the rotate group. The deeply lobing corolla and concave foveae may be ancestral in the Swertiinae, while the tubular corolla and the protruding glands may have undergone convergent evolution.

Characterization of metabolites of sweroside in rat urine using ultra-high-performance liquid chromatography combined with electrospray ionization quadrupole time-of-flight tandem mass spectrometry and NMR spectroscopy

Sweroside, a major active iridoid in Swertia pseudochinensis Hara, is recognized as an effective agent in the treatment of liver injury. Based on previous reports, the relatively short half-life (64 min) and poor bioavailability (approximately 0.31%) in rats suggested that not only sweroside itself but also its metabolites could be responsible for the observed hepato-protective effect. However, few studies have been carried out on the metabolism of sweroside. Therefore, the present study aimed at identifying the metabolites of sweroside in rat urine after a single oral dose (100 mg/kg). With ultra-high-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (UHPLC/Q-TOF-MS), the metabolic profile revealed 11 metabolites in rat urine, including phase I, phase II and aglycone-related products. The chemical structures of metabolites were proposed based on accurate mass measurements of protonated or deprotonated molecules and their fragmentation patterns. Our findings showed that the aglycone of sweroside (M05) and its glucuronide conjugate (M06) were principal circulating metabolites in rats. While several other metabolic transformations, occurring via reduction, N-heterocyclization and N-acetylation after deglycosylation, were also observed. Two metabolites (M05 and M06) were isolated from the rat urine for structural elucidation and identifcation of reaction sites. Both M05 and M06 were characterized by 1H, 13C and two-dimensional nuclear magnetic resonance (NMR) spectroscopy. UHPLC/Q-TOF-MS analysis has provided an important analytical platform to gather metabolic profile of sweroside.

Effect of leaf extract of Aegle marmelose in diabetic rats

Alloxan induced animal model was used to evaluate the potential antidiabetic effect of A . marmelose leaf extract. The diabetic animals were given insulin injection and another group A . marmelose leaf extract orally. It maintained the weight of the animals near to the control rats but a significant decrease in weight was noted it diabetic animals without any treatment . The blood elucose level in 'treated animals were near to that of control ones. Also a significantly increased glucose tolerance was observed in animals orally given the leaf extract prior to the experiment . A significant decrease in liver glycogen ( 1.24 -.07 s!/ 100 g of wet tissue) was observed in diabetic rats which was brought to almost the normal level (I.84- . 14 g; 100 g) with Icaf extract treatment. Blood urea and serum cholesterol increased ( 62.66 - 3.50 and 192.67± 13.64 mg' dl) significantly in alloxxan diabetic rats . The leaf extract treatment decreased the blood urea and serum . cholesterol (37.83 - 3.97 and 99?0±8.43 mg/dl ) to that of control ones . A similar effect was seen with insulin treatment . The results indicate that the active principle in .4. marmelose leaf extract has similar hypoglycaemic activity to insulin treatment.

Pollen records from two outcrop profiles in the Kakitu Mountain of Tibet

There is a great similarity between pollen types which occur in the early Holocene NE Tibetan pollen spectra and those which are commonly considered to be typical for the Würm Late Glacial period in Central Europe and for the Würm Pleniglacial period in Southern Europe. Evidently, this similarity is due to a remarkable general conformity of plant taxa growing in cold-arid regions of the northern hemisphere. The improvement of the climate and the retreat of the glaciers that commenced at the end of the Würm period had already terminated definitely before 9500 BP. In addition, the climatic situation as well as the vegetation belts must have remained rather constant during the following 3000 yr, i.e. through most parts of the climatic optimum of the Holocene.

AMS radiocarbon dates and pollen analysis of ODP Hole 175-1078C

ODP Site 1078 situated under the coast of Angola provides the first record of the vegetation history for Angola. The upper 11 m of the core covers the past 30 thousand years, which has been analysed palynologically in decadal to centennial resolution. Alkenone sea surface temperature estimates were analysed in centennial resolution. We studied sea surface temperatures and vegetation development during full glacial, deglacial, and interglacial conditions. During the glacial the vegetation in Angola was very open consisting of grass and heath lands, deserts and semi-deserts, which suggests a cool and dry climate. A change to warmer and more humid conditions is indicated by forest expansion starting in step with the earliest temperature rise in Antarctica, 22 thousand years ago. We infer that around the period of Heinrich Event 1, a northward excursion of the Angola Benguela Front and the Congo Air Boundary resulted in cool sea surface temperatures but rain forest remained present in the northern lowlands of Angola. Rain forest and dry forest area increase 15 thousand years ago. During the Holocene, dry forests and Miombo woodlands expanded. Also in Angola globally recognised climate changes at 8 thousand and 4 thousand years ago had an impact on the vegetation. During the past 2 thousand years, savannah vegetation became dominant.

Palynology on sediment profile Tso Kar in Ladakh

Palynological investigation of a 410 cm long core section from Tso Kar (33°10'N, 78°E, 4527 m a.s.l.), an alpine lake situated in the arid Ladakh area of NW India at the limit of the present-day Indian summer monsoon, was performed in order to reconstruct post-glacial regional vegetation and climate dynamics. The area was covered with alpine desert vegetation from ca. 15.2 to 14 kyr BP (1 kyr=1000 cal. years), reflecting dry and cold conditions. High influx values of long-distance transported Pinus sylvestris type pollen suggest prevailing air flow from the west and northwest. The spread of alpine meadow communities and local aquatic vegetation is a weak sign of climate amelioration after ca. 14 kyr BP. Pollen data (e.g. influx values of Pinus roxburghii type and Quercus) suggest that this was due to a strengthening of the summer monsoon and the reduced activity of westerly winds. The further spread of Artemisia and species-rich meadows occurred in response to improved moisture conditions between ca. 12.9 and 12.5 kyr BP. The subsequent change towards drier desert-steppe vegetation likely indicates more frequent westerly disturbances and associated snowfalls, which favoured the persistence of alpine meadows on edaphically moist sites. The spread of Chenopodiaceae-dominated vegetation associated with an extremely weak monsoon occurred at ca. 12.2-11.8 kyr BP during the Younger Dryas interstadial. A major increase in humidity is inferred from the development of Artemisia-dominated steppe and wet alpine meadows with Gentianaceae after the late glacial/early Holocene transition in response to the strengthening of the summer monsoon. Monsoonal influence reached maximum activity in the Tso Kar region between ca. 10.9 and 9.2 kyr BP. The subsequent development of the alpine meadow, steppe and desert-steppe vegetation points to a moderate reduction in the moisture supply, which can be linked to the weaker summer monsoon and the accompanying enhancement of the winter westerly flow from ca. 9.2 to 4.8 kyr BP. The highest water levels of Tso Kar around 8 kyr BP probably reflect combined effect of both monsoonal and westerly influence in the region. An abrupt shift towards aridity in the Tso Kar region occurred after ca. 4.8 kyr BP, as evidenced by an expansion of Chenopodiaceae-dominated desert-steppe. Low pollen influx values registered ca. 2.8-1.3 kyr BP suggest scarce vegetation cover and unfavourable growing conditions likely associated with a further weakening of the Indian Monsoon.

Distribution of pollen and spores in sediments of ODP Hole 175-1078C

The distribution of pollen in marine sediments is used to record vegetation change on the continent. Generally, a good latitudinal correspondence exists between the distribution patterns of pollen in the marine surface sediments and the occurrence of the source plants on the adjacent continent. To investigate land-sea interactions during deglaciation, we compare proxies for continental (pollen assemblages) and marine conditions (alkenone-derived sea surface temperatures) of two high-resolution, radiocarbon-dated sedimentary records from the tropical southeast Atlantic. The southern site is located West of the Cunene River mouth; the northern site is located West of the Angolan Huambe Mountains. It is inferred that the vegetation in Angola developed from Afroalpine and open savannah during the last Glacial maximum (LGM) via Afromontane Podocarpus forest during Heinrich Event 1 (H1), to an early increase of lowland forest after 14.5 ka. The vegetation record indicates dry and cold conditions during the LGM, cool and wet conditions during H1 and a gradual rise in temperature starting well before the Younger Dryas (YD) period. Terrestrial and oceanic climate developments seem largely running parallel, in contrast to the situation ca. 5° further South, where marine and terrestrial developments diverge during the YD. The cool and wet conditions in tropical West Africa, South of the equator, during H1 suggest that low-latitude insolation variation is more important than the slowdown of the thermohaline circulation for the climate in tropical Africa.

Pollen profiles from three former lakes in the Lake Garda area

1. Late glacial and postglacial sediments from three former lakes in the Lake Garda area (Southern Alps) were investigated. 2. The pollen diagram from Bondone (1550 m) shows an older phase rich in NAP. A younger one corresponds with the Younger Dryas time according to two radiocarbon determinations. In the Preboreal no climatic deterioration could be found. 3. At first plants, which are nowadays typical for snow-ground, pioneer and dwarf shrub associations, immigrated into the surroundings of Bondone. In Alleröd times larch and pine appeared as the first trees. At the beginning of the Preboreal dense forest existed in that region. During the Alleröd timber line was at about 1500 m. 4. In the pollen diagrams from Saltarino (194 m) and Fiavè (654 m) an oldest period rich in NAP is followed by two stadial and two interstadial phases. Tree birches and larches immigrated during the oldest interstadial phase. 5. In the case of Saltarino and Fiavè only a preliminary dating could be made. A correlation seems to be possible with diagrams published by Zoller as well as with the diagram of Bondone. Discrepances in dating, which arise then, are discussed. According to the two possibilities of dating the youngest stadial is synchronous either with the so-called Piottino stadial or the Younger Dryas time. Consequently the oldest interstadial phase of Saltarino corresponds either with the Bölling or with a pre-Bölling interstadial. The last possibility seems to be more probable. 6. In the southern part of the Lake Garda area reforestation was preceded by a long shrub phase mainly with Juniperus. At about 650 m there was a period with Pinus mugo and only with a small amount of Juniperus before reforestation. A phase with Betula nana well known from areas north of the Alps could nowhere be found. 7. In the area under study larch appeared as the first tree. Lateron it has been the most important constituent of the forests near timber line. Birch, which plays an important role as a pioneer tree in Denmark - for instance at the transition of the pollen zones III/IV - as well as in Southern Germany during Bölling time, was of less importance at the southern border of the Alps. In that area the spreading of Pinus occurred very early causing dense forests. 8. During the last stadial phase (probably Younger Dryas time) dense forests with Pinus and Larix existed at 650 m. In the lower part of the Lake Garda area, however, both thermophilous trees as Quercus and herbs frequently occurred. This leads to the conclusion that during this time tree growth was limited by dryness in lower altitudes of the border of the Southern Alps. Pinus and Juniperus, however, do not show higher values in this period, a fact which cannot yet be explained. 9. A list of plants, which were found in the sediments, is compiled. Helodium lanatum, Dictamnus albus, Mercurialis cf. ovata, Buxus, Cerinthe cf. minor, Onosma, Anthericum and Asphodelus albus are findings, which are of special interest for the history of the flora of that region.