Phylogenetic implications of endosperm cell wall morphology in Douglasia, Androsace, and Vitaliana (Primulaceae)

We investigated differences in endosperm cell wall thickening in three genera of Primulaceae; seven species of Douglasia , 28 species of Androsace representing the four sections of the genus, and the single species of the genus Vitaliana . Endosperm cell walls have irregular wall thickenings and narrow constrictions and characterize all Douglasia species and Vitaliana , whereas evenly thickened cell walls without constrictions were found in the endosperm of Androsace and Primulu . The endosperm character supports the monophyly of Douglasia and Vitaliana , and we discuss the phylogenetic implications of this conclusion.     

A new Douglasia (Primulaceae) from Idaho

Douglasia idahoensis, a new species endemic to Idaho and Valley counties, Idaho, a close relative of D. montana, is characterized by its succulent foliage, several-flowered umbels, 5–9 lanceolate bracts, short peduncles, and allopatric distribution. Chromosome number is reported as n = 18. Previous taxonomic works have included this species either with D. montana or with D. laevigata.     

点地梅属的分子系统学、生物地理学和垫状形态的趋同进化

报道了青藏高原地区的点地梅属Androsace L.及羽叶点地梅属Pomatosace Maxim.共14种29个居群的ITS与trnL-F DNA序列各27与25条;并结合已报道相关种类的有关序列,构建了“点地梅群”的分子系统发育树。研究发现“点地梅群”的4个属为一单系类群,含有两个稳定的分支：一支全部由点地梅属的种类组成,另一支分别由羽叶点地梅属、Douglasia Lindley、Vitaliana Sesler和9种点地梅属植物组成;点地梅属裂叶组sect. Samuelia Schlechtd.的3个种与点地梅组sect. Androsace的2个种在3套序列分析中位于不同的系统位置。各分支基部的种都分布在中国东南部及青藏高原东部,分子地理标记的结果支持形态学提出该地区为“点地梅群”植物起源地的假设。从青藏高原东部地区向欧洲及其他北半球地区存在不同时期内多个进化支的多次扩散。粗略的时间估算表明该群植物可能是在第三纪的中新世以来才开始发生的。垫状种类分别在青藏高原和欧洲独立起源,而在青藏高原地区的分化要早于在欧洲的分化,在前一地区可能与青藏高原自中新世开始发生的造山运动、形成高海拔的山地有关,而在后一地区则是与第三纪末至第四纪的冰期气候反复波动有关。垫状植物在青藏高原上的大规模分布则可能较晚,与冰期结束后全新世晚期气候再次变冷有关。一些物种种内的遗传分化也可能部分反映了气候来回波动中它们在高原上的退缩和再扩张过程     

Pollen morphology in Primula sect. Carolinella (Primulaceae) and its taxonomic implications

Pollen morphology in Primula section Carolinella has been investigated for the first time. Seven of the nine species constituting the section were available for study, i. e., P. cardioeides, P. chapaensis, P. intanoensis, P. kwangtungensis, P. kweichouensis, P. partschiana , and P. rugosa, A considerable variation in pollen morphology was found among the investigated species, particularly in number and arrangement of the apertures. Pollen of different species were either tricolpate, tricolporate, trisyncolpate, or polycolpate. Within Primula , the section Carolinella is diagnosed by having calyptrate capsules and leaves with revolute vernation, but the variation in pollen morphology indicates that this group is heterogeneous, and that either polycolpate pollen or a capsular lid has evolved more than once in the genus Primula.     

Traces of ancient range shifts in a mountain plant group (Androsace halleri complex, Primulaceae)

Phylogeographical studies frequently detect range shifts, both expansions (including long-distance dispersal) and contractions (including vicariance), in the studied taxa. These processes are usually inferred from the patterns and distribution of genetic variation, with the potential pitfall that different historical processes may result in similar genetic patterns. Using a combination of DNA sequence data from the plastid genome, AFLP fingerprinting, and rigorous phylogenetic and coalescence-based hypothesis testing, we show that Androsace halleri (currently distributed disjunctly in the northwestern Iberian Cordillera Cantábrica, the eastern Pyrenees, and the French Massif Central and Vosges), or its ancestor, was once more widely distributed in the Pyrenees. While there, it hybridized with Androsace laggeri and Androsace pyrenaica, both of which are currently allopatric with A. halleri. The common ancestor of A. halleri and the north Iberian local endemic Androsace rioxana probably existed in the north Iberian mountain ranges with subsequent range expansion (to the French mountain ranges of the Massif Central and the Vosges) and allopatric speciation (A. rioxana, A. halleri in the eastern Pyrenees, A. halleri elsewhere). We have thus been able to use the reticulate evolution in this species group to help elucidate its phylogeographical history, including evidence of range contraction.     

雅江点地梅（报春花科）3个居群的核型和倍性变化

首次报道了雅江点地梅（Androsace yargongensis)3个居群的染色体数目和核型,对倍性也进行研究。3个居群的染色体数目（2n),核型公式（KF）,染色体相长度组成（C．RL）,核型不对4称系数（As,K%)和核型类型（KT）分别为：野牛沟居群2n=40,KF=36m(1SAT) 2SM 2ST b,C,RL=2L 14M2 22M1 2S 2bS,As.K=54.75%,KT=2A;巴颜喀拉山居群2n=40,KF=36m 2sm 2st 1b,C.RL=4L 16M2 18M1 2S 1bS,As.K=56.31%,KT=2B;达坂山居群2n=60,KF=40m 14sm 6st,C.RL=4L 24M2 26M1 6S,As.K=59.56%,KT=2B。根据3个居群的染色体和核型不对称性与居群所在地的地理位置,认为雅江点地梅核型和倍性的演化与高海拔生态环境和寒冷、干旱的气候加剧有密切关系。     

On the identity of Androsace sarmentosa var. yunnanensis (Primulaceae) from Yunnan,China

Androsace sarmentosa Wall. var. yunnanensis R. Knuth is placed in synonymy with A. sublanata Hand.‐Mazz. based on critical examinations of herbarium specimens and living plants. In addition, a lectotype is designated for A. sarmentosa var. yunnanensis.     

Phylogenetic implications of corolla morphology in subfamily Barnadesioideae (Asteraceae)

The previously insignificant and small South American subtribe Barnadesiinae of tribe Mutisieae has been shown recently to be ancient within Asteraceae. Due to absence of a 22 kb diagnostic chloroplast inversion, plus other features, this subtribe has been elevated to subfamilial status as Barnadesioideae, now containing 90 species in nine genera. Recent cladistic analyses at the generic and specific levels based on morphology and DNA sequences (ITS and trnL intron) have revealed different relationships among taxa of the subfamily. To better understand these conflicts, we analyze specific morphological features of corollas (shape and vascularization) to develop trends (trees) in these features based on minimal structural change (i.e., morphological parsimony), and to compare these with relationships among genera derived from the two recent cladistic analyses. We define six principal types of corollas in Barnadesioideae (tubular, split, double split, ligulate, subbilabiate and bilabiate) and six principal types of corolla vascularization patterns (combinations of presence or absence of central bundles, fusion of adjacent bundles and fusion of bundles at the apex of corolla lobes). In all features we assume character states in Calyceraceae to be ancestral. In corolla shape, from tubular ancestry, we hypothesize two general evolutionary trends within the subfamily: (1) splitting of the tube, and (2) flattening of the tube. In vascularization of corollas, from an ancestral condition of one central and one lateral bundle in each corolla lobe and all traces fused at the apex, we hypothesize four basic trends: (1) gain or (2) loss of lateral vascular traces in each lobe, (3) loss of the central vein, and (4) loss of fusion of traces in lobe apices. These morphological trends allow tests of the two previous phylogenetic hypotheses by (1) counting step changes (following steps in the morphological network) in the two characters on the two competing phylogenetic trees and (2) constructing an index of morphological advancement for each genus (based on morphological trees of the two characters) and correlating these with cladistic distances within the two phylogenies. Results of both tests reveal the molecular phylogeny to be more compatible with evolutionary inferences from the two morphological features. With Fulcaldea excluded, a highly significant correlation is seen between morphological advancement and cladistic distance in the molecular phylogeny.     

Pollen grain morphology ofCoris (Primulaceae)

Pollen grain morphology, sculpturing, and wall ultrastructure are investigated in two species ofCoris (Primulaceae),C. monspeliensis L. andC. hispanica Lange. The study includes both acetolysed and unacetolysed pollen. No evidence of any major palynological difference is recorded between these two species, apart from a somewhat larger pollen inC. monspeliensis. However,Coris can be distinguished from the remaining members of thePrimulaceae by the conjunction of relatively large pollen grains, prominent margo, and particular tectal pattern causing a reticulate surface with minute luminal perforations decreasing towards the colpi. From both these distinctive features, and others typically primulaceous, some evolutionary considerations are inferred. Finally, the higher proportion of irregular grains inC. hispanica is interpreted in light of environmental stress.     

Disjunctions in relict alpine plants: phylogeography of Androsace brevis and A. wulfeniana (Primulaceae)

Amplified Fragment Length Polymorphism (AFLP) was used to clarify the glacial history of the rare, disjunctly distributed, alpine cushion plant Androsace wulfeniana , which is endemic to the Eastern Alps (Austria and Italy). Disjunct populations in the Dolomites are genetically very distinct from those in the main distributional area. It is hypothesized that they are descendants of long-term isolated glacial survivors and are not a result of recent long-­distance dispersal. Within the main distributional area of the species in the central Eastern Alps, two groups of ­populations can be distinguished, which are congruent with hotspots of rare relictual vascular plant taxa. In the ­taxonomically closely related A. brevis growing in the Southern Alps (Italy, Switzerland), no genetic-geographical structure was found. Genetic variation is extremely low in disjunct populations of A. wulfeniana in the Dolomites and in A. brevis . In contrast, in the main distributional area of A. wulfeniana , genetic variation is similar to that of the colonizing widespread congener A. alpina .  © 2003 The Linnean Society of London, Botanical Journal of the ­Linnean Society , 2003, 141 , 437–446.     

Environmental influences on the phenology and abundance of flowering by Androsace septentrionalis (Primulaceae)

We studied the timing and abundance of flowering by Androsace septentrionalis L. (Primulaceae), an indeterminate winter annual or short-lived perennial, in 2 × 2 m plots at the Rocky Mountain Biological Laboratory in Colorado, USA, from 1982 to 2000. Flowers were counted every other day for most or all of the growing season in seven plots in a rocky meadow habitat and nine plots in a wet meadow habitat. The phenology and abundance of flowering were both highly variable, with mean dates of first flowering ranging from 16 May to 12 July and maximum daily counts of flowers ranging from 1 to 1187. Snowmelt date was the primary determinant of timing of flowering. For rocky meadow plots, the previous year's summer precipitation and the current year's average minimum temperature in May had significant effects on maximum number of flowers produced, but no environmental variable we considered was significantly correlated with flower abundance in the wet meadow plots. Length of flowering in individual plots ranged from 2 to 85 d, and many plot-years had both primary (about 1 mo) and secondary (about 10-12 d) flowering periods. The predicted increase in variability of precipitation accompanying climate change will affect negatively the long-term abundance and persistence of this species at our study site.     

Phylogeography of the High Alpine Cushion Plant Androsace alpina (Primulaceae) in the European Alps

Abstract: Recent studies elucidating the glacial history of alpine plants have yielded controversial results. While some have favoured glacial survival on mountain tops above the glaciers (nunataks), others did not find support for this hypothesis. Furthermore, all of the published phylogeographic patterns are strikingly different. In order to provide more data for a future comparative phylogeographical approach, we investigated 53 populations of the high alpine cushion plant Androsace alpina (Primulaceae), endemic to the European Alps, using amplified fragment length polymorphism (AFLP). While Principal Co-ordinate Analysis (PCoA) of populations revealed four genetically-defined phylogeographical groups corresponding to geographic regions, Neighbour Joining analysis (NJ) separated only three groups. Mantel tests were used to assess the goodness-of-fit between the grouping in PCoA and the genetic similarity matrix, and these showed high similarity between the two eastern phylogeographical groups. This, together with other lines of evidence, is interpreted as an indication for colonization of the eastern part of the distributional range of A. alpina from westerly adjacent populations. The phylogeographical groups can all be related to potential refugia for alpine plants, based on geological and palaeoclimatological data. However, due to the comparatively weak phylogeographical structure, our data do not allow us to rule out glacial survival on nunataks in central parts of the Pleistocene ice shield.     

A statistical approach to the morphological variability of Androsace himalaica (Knuth) Handel-Mazetti (Primulaceae) in Pakistan

The species Androsace himalaica is found lo comprise two spatially separate populations. Statistical analysis of bract and hair length show that the tax in question can be distinguished morphologically and recognized as subspecies.     

Seed morphology and endosperm structure of selected species of Primulaceae, Myrsinaceae, and Theophrastaceae and their systematic importance

Seed size and shape, seed coat surface pattern, seed coat thickness, and endosperm structure were investigated in Androsace septentrionalis, Cortusa matthioli, Hottonia palustris, Primula elatior, Soldanella carpatica (Primulaceae), Anagallis arvensis, A. minima, Cyclamen purpurascens, Glaux maritima, Lysimachia nemorum, L. vulgaris, Trientalis europaea (Myrsinaceae), and Samolus valerandi (Theophrastaceae). Three seed size categories were distinguished on the basis of biometric measurements. Almost all seeds examined were found to be small with an angular shape classified as sectoroid or polyhedral. A new type of seed shape, suboval, was identified for H. palustris. Cyclamen purpurascens seeds differed from seeds of all other species examined because of their large size, subglobose shape, and concave hilar area. Despite the different shape types, the length/width ratio of the seeds examined was constant, while their hilum length/width ratio was a highly variable feature. Three types of seed surface patterns were observed: (1) reticulate, (2) tuberculate with secondary striations, and (3) poroid-alveolate with the presence of a spongy outer layer. For seeds of Anagallis arvensis, A. minima, Cortusa matthioli, Lysimachia nemorum, and Soldanella carpatica, secondary seed sculpture was described. The seed coats of all species examined were two-layered, and great differences in testa thickness were found (9.9?C128.6???m). In general, seeds of the Myrsinaceae species were more often characterized by thick testa. Different proportions in thickness of the inner and outer testa layers were observed. In seeds with reticulate seed patterns, the inner testa layer was twice to several times thicker than the outer layer, while the opposite proportions were observed in seeds with the tuberculate or poroid-alveolate seed sculpture pattern. In seeds of all species examined, oxalate crystals were present on the surface of the inner testa layer. Thus, the presence or absence of oxalate crystals in testa is not a feature distinguishing species with angular or subglobose seeds. Four types of endosperm structure were identified according to the thickness of the endosperm cell walls and the relief of their inner surface: (1) with evenly thickened and smooth cell walls, (2) with evenly thickened cell walls and circular or helical thickenings on their inside surfaces, (3) with very thick, but not evenly thickened cell walls with constrictions (??pitted??), and (4) with very thin papery and undulate cell walls. There is no rule concerning the seed shape, type of the seed sculpture, testa thickness, or endosperm structure that corresponds to the family affiliation of the species examined.     

Reciprocal Pleistocene origin and postglacial range formation of an allopolyploid and its sympatric ancestors (Androsace adfinis group,Primulaceae)

The biogeographic history of polyploids and their lower-ploid ancestors is an important feature to achieve a better understanding of polyploid evolution. This is exemplified here using the ecologically congruent members of the Androsace adfinis group (Primulaceae) endemic to the southwestern European Alps. Employing relative genome size, AFLP fingerprint and chloroplast sequence haplotype data, we show that Androsace brigantiaca is a recent (probably no more than 0.2 million years) allopolyploid derivative of the geographically close A. adfinis and A. puberula, which formed reciprocally in a comparatively restricted area in the southern Southwestern Alps. Bayesian admixture analysis—also of artificial additive AFLP profiles—shows that the nuclear genome of A. brigantiaca is significantly biased towards the puberula-genome irrespective of maternal parentage. Nevertheless, there is no evidence for genetic interaction (hybridization, introgression) of A. brigantiaca with either of its ancestors, including the widely sympatric A. puberula. Sympatry might be facilitated by ecological displacement on a local scale or might be a transitory phase on the way to competitive replacement via, for instance, polyploid superiority.     

国产6种点地梅属植物的核型及其系统学意义

报道了点地梅属6种12个居群的染色体数目和核型。它们的染色体数目(2n)、核型公式(KF)、染色体相对长度组成(CRL)、核型不对称性系数(A．sK%)和核型类型(KT)分别为：点地梅在南京的2个居群都是2n=2x=20,KF=18m 2sm,CRL=2L 6M2 10M1 2S,核型KT属于1A型,但核型不对称性系数As．K%分别是55.04％和56．71％;北点地梅在内蒙古锡林郭勒和白音锡勒居群的2n=2x=20,KF分别为16m 2sm 2st 1b和16m 2sm 2st 4b,染色体相对长度组成分别是14M2 4M1 2S 1b和12M2 6M1 2S 4b,核型不对称性系数As．K％分别是57．65％和58．86％,属2A型和2B型;高原点地梅在青海玛沁县昌马河居群和兴海县温泉居群都是2n=2x=20,KF=10m 8sm 2st。但相对长度组成分别为12M2 8M1和4L 6M2 6M1 4S,As．K％分别是60．35％和62．57％,属2A型和2B型;雅江点地梅在青海玛多县巴颜喀拉山居群和大通县达坂山居群分别为2n=4x=40和2n=6x=60,KF=36m 2sm 2st和KF=46m 10sm 4st 2b,CRL=2L 20M2 14M1 4S和CRL=6L 30M2 16M1 8S 2b,As．K％分别为55．62％和58．31％,核型均属于2B;巴颜喀拉山北坡的鳞叶点地梅2n=40、60、80。西藏点地梅青海湖居群中有2种细胞型：①2n=2x=24,KF=12m 6sm 6st 4b,CRL=6L 6M2 8M1 4S 4b,As．K％=65．74％,核型属2B;②2n=2x=22,KF=14m 4sm(2SAT) 4st,CRL=4L 6M2 8M1(2sAT) 4S,As．K％=63．40％,核型也属于2B。西宁西山湾居群也有2种细胞型：①2n=3x=36,KF=36m,CRL=4L 12M2 20M1,As．K％=54．82％,核型属1A;②2n=3x=33,KF=33m,CRL=3L 12M2 18M1,As．K％=52．11％,核型属1A。点地梅属的染色体原始基数可能是x=10,在种间或种内观察到有3种核型变化：染色体非整倍性变化、多倍化和核型不对称性变化。将2倍体居群的核型和不对称性进行比较,可以看出点地梅是较对称的核型。因此,在研究的种中应是比较原始的类群。北点地梅的核型不对称性和进化程度高于点地梅而低于高原点地梅和西藏点地梅。染色体多倍化的雅江点地梅、鳞叶点地梅和西藏点地梅等在核型上也许是最进化的类群。     

细蔓点地梅在豫西南的发现及其微形态特征和系统演化意义

该文报道了河南报春花科点地梅属1新记录种,即细蔓点地梅(Androsace cuscutiformis Franch.)。该种因其叶片显著分裂,裂片深达叶中部,具有典型匍匐茎而明显区别于该属在河南分布的其它种类,同时编制了河南点地梅属植物检索表,并对该种的叶表皮和花粉形态特征进行了观察和描述。结果表明:该种上下表皮细胞都为不规则多边形,垂周壁深波状,下叶表皮具有椭圆形气孔器,上下表皮都具有坑状雕刻的多细胞毛和球状蜡质,叶表皮形态特征和毛的类型可能为点地梅属系统分类和演化提供参考。花粉椭圆形,具三孔沟,沟较狭窄,花粉外壁具有坑状雕刻,未发现有萌发孔,该种是点地梅属裂叶组内最小的花粉粒。裂叶组因叶大、具长柄、叶缘有齿或深裂而明显区别于该属的其它组,该种与其近缘种腋花点地梅(A.axillaris)和掌叶点地梅(A.geraniifolia)间断分布的地理格局和特殊的繁殖方式表明该种很可能为点地梅属的原始类群在伏牛山、秦岭南坡及大巴山的孑遗植物。