A Study on the Genus Saxifraga L. from China

This paper presents a system of the genus Saxifraga L. from China, recognizes 2 subgenera, 8 sections, 7 subsections (including 1 new subsection), 31 series (including 23 new series), 4 subseries (new subseries) and 203 species (including 2 new species and 4 new varieties). The new taxa, statuses, combinations and names in this paper are as follows: Sect. Biro- stres (Gornall) C. Y. Wu et J. T. Pan, stat. nov.,; Sect. Punctatae (Engl.) J. T. Pan, stat. nov.; Ser. Rufescentes J. T. Pan, ser. nov.; Saxifraga lonshengensis J. T. Pan, sp. nov.; S. rufescens Balf. f. var. uninervata J. T. Pan, var. nov.; S. rufescens Balf. f. var. flabellifolia C. Y. Wu et J. T. Pan, nom. nov.; Ser. Stonoliferae J. T. Pan, ser. nov.; Ser. Stellariifoliae (Engl. et Irmsch.) J. T. Pan, stat. nov.; Subser. Aristulatae J. T. Pan, subser. nov.; Subser. Montanae J. T. Pan, subser, nov.; Saxifraga ciliatopetata (Engl. et Irmsch.) J. T. Pan var. ciliata J. T. Pan, var. nov.; Subser. Gonggashanenses J. T. Pan, subser, nov.; Subser. Car- diophyllae J. T. Pan, subser. nov.; Saxifraga egregia Engl. var. xiaojinensis J. T. Pan, var. nov.; Ser. Caveanae J. T. Pan, ser. nov.; Ser. Heterocladoideae J. T. Pan, ser. nov.; Ser. Chumbienses J. T. Pan, ser. nov.; Ser. Bulleyanae J. T. Pan, ser. nov.; Ser. Brachypodae C. Y. Wu et J. T. Pan, ser. nov.; Ser. Erinaceae J. T. Pan, ser. nov.; Saxifraga substrigosa J. T. Pan var. gemmifera J. T. Pan, var. nov.; Ser. Umbellulatae J. T. Pan, ser. nov; Ser. Yu- shuenses J. T. Pan, ser. nov.; Ser. Ungviculatae J. T. Pan, Ser. nov.; Ser. Punctu- latae J. T. Pan, ser. nov.; Ser. Candelabriformes J. T. Pan, ser. nov.; Ser. Tanguti- cae J. T. Pan, ser. nov.; Saxifraga tangutica Engl. var. platyphylla (H. Smith) J. T. Pan, comb. nov.; Ser. Yaluzangbuenses J. T. Pan, ser. nov.; Ser. Jainzhuglaenses J. T. Pan, ser. nov.; Saxifraga jainzhulaensis J. T. Pan, sp. nov.; Ser. Jacquemontianae J. T. Pan, ser. nov.; Ser. Nanae J. T. Pan, ser. nov.; Subsect. Microgynae J. T. Pan, subsect. nov.; Ser. Nangxi- anenses J. T. Pan, ser. nov.; Ser. Mucronulatae J. T. Pan, ser. nov.; Ser. Parkaenses J.T. Pan, ser. nov.; Ser. Deqenenses J. T. Pan, ser. nov.; Saxifraga mucronulatoides J. T. Pan, nom. nov.     

The typification of Lolium perenne L. and Loliutn temulentum L. (Poaceae)

LOOS, B. P. & JARVIS, C. E., 1992. The typification of Lolium perenne and Lolium temulentum (Poaceae). The typification of the Linnaean species Lolium perenne and Lolium temulentum has been studied. Lolium perenne is typified by material in LINN, as proposed by Terrell, but it has been necessary to select a lectotype for L. temulentum , and material in the Burser herbarium (UPS) has been chosen for this purpose. The study shows that although Linnaeus used awns as a diagnostic character to distinguish the two species, he was aware of the intraspecific variability in this character.     

虎耳草属异叶虎耳草复合群的数量分类学研究

山羊臭组（Saxifraga sect. Ciliatae Haworth）隶属于虎耳草属（Saxifraga Tourn. ex L.）,具有极高的物种丰富度,但山羊臭组内部的系统发育关系一直都未能很好解决。唐古拉亚组（S. subsect. Hirculoideae Engl.）是山羊臭组中最大的亚组,主要分布于青藏高原及其周边地区。根据形态特征,可将唐古拉亚组划分为3个复合群,其中叶背边缘有突起叶脉的物种被归入异叶虎耳草复合群（S. diversifolia complex）。本研究通过标本查阅,选取异叶虎耳草复合群24个物种、2变种共657份标本,对其24个定性性状信息进行主成分分析和聚类分析;获取443条地理分布信息,构建复合群的分布式样。特征值大于1的前7个主成分的累计贡献率较低,仅为67.748%。“茎生叶是否具柄”“中下部茎生叶形态”“花序类型”“中下部茎生叶大小”“萼片脉纹于先端汇合”“叶基心形”等性状对前3个主成分的贡献值大,可作为异叶虎耳草复合群物种分类与鉴定的关键性状。基于形态聚类结果和地理分布式样,可将异叶虎耳草复合群划分为3个分支：喜马拉雅山南坡分支、环四川盆地山区分支以及横断山分支（包含一个广布种S. egregia）。主成分分析结果支持将异叶虎耳草复合群划分为3个分支。     

Low temperature acclimation of guard cell chloroplasts by the arctic plant Saxifraga cernua L.

Abstract. The potential for thermal acclimation of photosynthetic electron transport by guard cell chloropiasts (GC ch) was assessed in epidermal peels taken from the abaxial side of Saxifraga cernua leaves grown at 20°C and 10°C. Chlorophyll a fluorescence induction kinetics measured in pairs of guard cells in individual stomata from tissue grown at 10 °C demonstrated a rise in the fluorescence to a maximum and a larger amplitude in variable fluorescence when measured at temperatures below 18°C than was seen in GC ch from tissue grown at 20°C. The rates of fluorescence quenching in 10°C-grown tissue were also faster than in 20°C-grown tissue when measured at temperatures below 18°C. State 1-State 2 transitions by GC ch were measured at selected temperatures between 5 and 25 °C as changes in the magnitude of the fluorescence emission maxima at 685, 695 and 730nm (F685, F695 and F730) measured at 77K. At measuring temperatures of 5 and 10°C, GC ch in tissue grown at 10 °C showed a greater transition to State 2 (a larger F730/F695 ratio) than did GC ch in tissue grown at 20 °C. At measuring temperatures of 20 and 25 °C, there was no difference in either the kinetics or the magnitude of the State 1 to State 2 transition in the two tissues. The ultrastructure of GC ch from tissues grown at 10 and 20 °C was also examined using transmission electron microscopy. Less than half (48%) of the grana from the higher temperature grown tissue had more than nine thylakoids/grana. Grana in GC ch which had developed at 10 °C showed a dramatic reduction in stacking, such that 85% of the grana contained no more than two thylakoids. The reduction in grana stacking was also accompanied by a decrease in the degree of appression of thylakoid membranes. The results demonstrate a capacity for thermal acclimation of GC ch function to low temperatures. This acclimation is associated with alterations in the chloroplast ultrastructure.     

On the gynodioecious polymorphism in Saxifraga granulata L. (Saxifragaceae)

Sexual and vegetative fitness components in hermaphrodite and female plants of the self-compatible, perennial herb Saxifraga granulata are compared using material derived from a gynodioecious population in northern England.
Females produced only 57% as many seeds as hermaphrodites, but their ovule offspring were 1.28 times as fit as those of hermaphrodites, and females were more vegetatively vigorous. The advantages to females in ovule offspring quality and in vegetative reproduction counteract their disadvantages in pollen and seed production and therefore probably play a role in the maintenance of the gynodioecious polymorphism. Pollination ecology, resource reallocation and inbreeding depression all appear to contribute to the observed sex differences in fitness.     

A new endemic species of Saxifraga L. from Spain

A recently erected species of Saxifraga (section Porphyrion ) endemic to the Picos de Europa (Cordillera Cantábrica) is described and illustrated. S. felineri P. Vargas resembles S. aretioides and S. ferdinandi-coburgi , although the habit and leaf shape are the main characters which support its identity. The taxonomic relationships of the three species are discussed, as well as aspects of the distribution and ecology of S. felineri.     

New Taxa of the Genus Saxifraga from China

Fifteen new taxa of the genus Saxifraga (Saxifragaceae) are described from China. They are Saxifraga erectisepala J. T. Pan, S. sublinearifolia J. T. Pan, S. rizhaoshanensis J. T. Pan, S. gedangensis J. T. Pan, S. sheqilaensis J. T. Pan, S. egregioides J. T. Pan, S. caveana W. W. Smith var. lanceolata J. T. Pan, S. subtsangchanensis J. T. Pan, S. brachypodoidea J. T. Pan, S. oreophila Franch. var. depaoshanensis J. T. Pan, S. subsediformis J. T. Pan, S. nangqenica J. T. Pan, S. medogensis J. T. Pan, S. paiquensis J. T. Pan and S. daochengensisJ. T. Pan.     

Natural hybridization in Saxifraga callosa Sm

Saxifraga callosa Sm. is an evergreen perennial species distributed from Eastern Spain, through the Western Alps and the Apennines, to southern Italy. The existence of high morphological variation within different subspecies indicates that phenotypic characters are useful but not sufficient taxonomic tools. Indeed, available morphological data already suggested that S. callosa subentity lantoscana may be an outcross between S. callosa and S. cochlearis. In this work, by analyzing ITS (Internal Transcribed Sequences), AFLP (Amplified Fragment Length Polymorphisms), and cpDNA (chloroplast DNA) markers, a comprehensive study of the genomic relationships among S. callosa and related species has been carried out. The sequence of the ITS region of S. callosa subentity lantoscana gave no conclusive results on the taxonomy status of S. callosa subentity lantoscana. On the other hand, the use of the "NewHybrids" software to analyze an AFLP data-set (208 polymorphic amplified fragments) supported a significant posterior probability that S. callosa subentity lantoscana individuals are natural hybrids between S. callosa and S. cochlearis. The level of introgression of genes from alien genomes was confirmed by a simpler and quick methodology that analyze length variation in cpDNA sequences.     

New Taxa of the Genus Saxifraga from Hengduan Mountains

Some new taxa of the genus Saxifraga (Saxifragaceae) are described from the Hengduan Mountains of China. They are Saxifraga yezhiensis C. Y. Wu, S. subomphalodifolia J. T. Pan, S. gonggashanensis J. T. Pan, S. setulosa C. Y. Wu, S. maxionggouensis J. T. Pan, S. yunlingensis C. Y. Wu, S. pellucida C. Y. Wu, S. baimashanensis C. Y. Wu, S. nanelloides C. Y. Wu, S. draboides C. Y. Wu, S. deqenensis C. Y. Wu, S. implicans var. weixiensis C. Y. Wu, S. omphalodifolia var. callosa C. Y. Wu, S. omphalodifolia var. retusopetala J. T. Pan, S. diversifolia var. angustibracteata (Engl. et Irmsch.) J. T. Pan, In addition, one newname (S. dianxibeiensis J. T. Pan) is included.     

藏药黑蕊虎耳草的化学成分

从黑蕊虎耳草(Saxifraga melanocentra)地上部分的乙醇提取物中分离得到10个化合物,通过波谱分析并与有关对照品比较,将其结构鉴定为山奈酚(1),槲皮素(2),山奈酚-3-O-β-D-葡萄糖苷(黄芪苷)(3),槲皮素-3-O-β-D-葡萄糖苷(4),山奈酚-3-O-芦丁糖苷(5),芦丁(6),2″-O-没食子酰芦丁(7),岩白菜素(8),没食子酸(9)和没食子酸甲酯(10),除化合物2、6、8和10外,其余6个化合物均为首次从虎耳草属植物中得到。这些成分的鉴定为该植物的药效学研究提供了新的化学依据。     

中国虎耳草属(虎耳草科)二新种————班玛虎耳草和丁青虎耳草

记载了中国虎耳草属Saxifraga二新种, 即班玛虎耳草S. banmaensis J. T. Pan和丁青虎耳草S. dingqingensis J. T. Pan。其中, 班玛虎耳草仅见于青海班玛, 与小伞虎耳草S. umbellulata Hook. f. &; Thoms.近缘, 但其萼片先端具软骨质短尖头, 花瓣线形, 非提琴状长圆形至提琴形, 基部无爪, 可资区别。丁青虎耳草见于西藏丁青, 与近加拉虎耳草S. llonakhensis W. W. Smith相似, 但其萼片3脉, 于先端汇合成1疣点, 花瓣具8痂体和4-5脉, 基部截形或近耳形, 可以区别。此两种均系中国特有种, 隶属于莲座状亚组subsect. Rosulares Gornall。     

A phylogenetic study of two recently described endemic species of the Saxifraga granulata group from the central-north Mediterranean region (Italy) and their position in the context of the series Saxifraga (Saxifragaceae)

On two small islands of the Tuscan Archipelago, two new endemic species of the Saxifraga granulata group, namely S. caprariae and S. montis-christi, were recently described on a morphological basis. This led us to investigate these species using a molecular approach involving the analysis of ITS and trnL-F regions. Our aims were: to highlight their phylogenetic traits; to confirm or reject the hypothesis that they are more closely related to S. corsica than to S. granulata; and to verify their phylogenetic position in the context of Saxifraga L. ser. Saxifraga. We considered all the species belonging to the ser. Saxifraga and some other species of sect. Saxifraga – a total of 19 species. We generated 10 new DNA sequences, six for ITS and four for trnL-trnF. We produced separate Bayesian and Maximum likelihood trees for both ITS and trnL-trnF regions and we analysed the genetic distances among the new endemics and the more closely related species. The phylogenetic analyses showed that S. caprariae and S. montis-christi are relatively well separated from S. granulata and more related to S. corsica. This supports the taxonomic treatment previously proposed. We showed that the results of our phylogenetic analysis are in agreement with our biogeographic knowledge of the Tuscan Archipelago and the neighbouring territories and emphasize the conservation relevance of these findings.     

喜马拉雅-横断山区优越虎耳草谱系地理学研究

利用叶绿体DNA非基因编码区rpl20-rps12和trnL-trnF作为分子标记,对喜马拉雅-横断山区优越虎耳草13个居群151个个体进行谱系地理学研究,旨在揭示优越虎耳草现有的遗传结构及其演化历程。共检测到19个单倍型,其中63%的单倍型为居群特有单倍型。研究还发现,优越虎耳草居群总的遗传多样性较高（H_t=0.868）,居群内平均遗传多样性较低（H_s=0.466）。分子变异分析（AMOVA）表明,优越虎耳草居群57.37%的遗传变异来自居群内,居群间遗传变异为42.63%。居群遗传分化系数N_st大于G_st（N_st=0.463,G_st=0.438,P>0.05）,但不显著,表明优越虎耳草在其整个分布范围内没有明显的谱系地理结构。中性检验结果表明,Tajima's D为负值（-1.348 32,P>0.05）而Fu's F_s*为正值（18.915 72,P>0.05）,但均不显著,结合歧点分布分析发现该物种在整个分布范围内未经历过居群扩张。此外,在本研究中优越虎耳草遗传多样性和核苷酸多样性较高的居群及大量特有单倍型在整个分布范围内随机分布,符合"微型避难所"假说。优越虎耳草居群在冰期可能随气候波动而发生分布范围的不断变化,最终在相互隔离的"高山岛屿"中发生异域分化,导致大量特有单倍型产生。因此,推测优越虎耳草与其生境中的乔木和灌木可能具有相似的谱系地理历史,它们可为优越虎耳草提供微型避难所而使之在冰期时保留下来。     

Haplotype and ribotype diversity of Saxifraga cuneifolia s. l. (Saxifragaceae)

Saxifraga cuneifolia L. (sect. Gymnopera, Saxifragaceae) is a plant distributed in the main mountain ranges of southern Europe, from the eastern Pyrenees to the eastern Carpathian. Currently, two subspecies are recognized based on morphological characteristics: S. cuneifolia subsp. cuneifolia grows in the Maritime Alps and North Apennines and S. cuneifolia subsp. robusta is located in the remaining area of distribution. A more delicate form and a smaller number of flowers in S. cuneifolia subsp. cuneifolia are the morphological characteristics that differentiate this subspecies from the widespread S. cuneifolia subsp. robusta. To explore the genetic diversity and the subspecific geographic patterns of S. cuneifolia s. l. we conducted a molecular study of nuclear and plastid sequences. Samples of S. cuneifolia s. l. have been analysed throughout the distribution area of this species. Our results, based on nuclear (ITS) and plastid (rbcL, trnL–F, and psbA–trnH) markers, showed a genetic characterization of both subspecies presenting discriminant haplotypes and ribotypes that confirm the current subspecific systematics.     

山地虎耳草转录组SSR信息分析

利用MISA（MicroSatellite）软件对山地虎耳草转录组拼接序列进行微卫星位点信息分析,为后期SSR标记的开发和物种遗传多样性检测提供候选序列。结果发现,在拼接得到的63 763条Unigene序列中含有4 622个SSR,发生频率为7.25%,有110种重复基元,平均每10.00 kB出现一个SSR位点。山地虎耳草转录组序列的SSR主要集中在三核苷酸重复（55.50%）,其次为二核苷酸重复（30.23%）。二核苷酸重复和三核苷酸重复中的优势重复基元分别为AG/TC和AAG/TTC。二核苷酸重复基元的重复次数类型最多,跨度最大,具有更高的多态性,三核苷酸次之,而四、五、六核苷酸重复类型很少。山地虎耳草转录组SSR以5~9次重复为主,且SSR数量随着重复次数的增加逐渐减少,基序长度主要集中于12~30 bp,多态性均在中等以上。     

不同温度处理对虎耳草叶片气体交换及叶肉结构的影响

在人工气候箱中对盆栽虎耳草进行处理,测定不同温度条件下虎耳草叶片光合特征、叶绿素含量、抗氧化酶活性、叶肉结构等生理形态指标。结果表明：低温处理后,虎耳草叶片净光合速率、气孔导度下降迅速,叶绿素含量最少,SOD、CAT活性最低,MDA含量最高,栅栏组织排列更紧密,移置正常温度下,光合速率能在短时间内恢复;高温处理的净光合速率下降速度不及低温处理,但叶片海绵组织显著增加,光合速率恢复较慢。     

Circumscription and phylogeny of Saxifraga sect. Ciliatae: Evidence from nrDNA ITS sequences

The largest section of the genus Saxifraga (Saxifragaceae), sect. Ciliatae, consists of 175 morphologically diverse species. This section is mainly distributed in the Qinghai-Tibetan Plateau and adjacent regions of southwest China and more than 80% of the total number of species are endemic to this region. It remains unknown whether this section is monophyletic and up to now no study has been conducted on the infra-sectional phylogeny. In this study, ITS sequences of the nuclear ribosomal DNA were firstly determined for 33 species mainly from this section and related sections. We further downloaded the corresponding sequences of the same DNA region for the other 22 species of Saxifraga and Mitella from GenBank. All sequences were together used to construct the phy-logenetic trees. The main implications of the phylogenetic analyses include: (1) sect. Ciliatae, as traditionally defined, constitutes as a monophyletic clade and its sister group is a well supported clade that includes species from 8 sections such as sect. Porphyrion, sect. Saxifraga and sect. Mesogyne; (2) three morphological subsections, i.e., subsect. Gemmiparae, subsect. Hirculoideae and subsect. Rosulares were tentatively recovered despite the relatively low statistic bootstrap support for the last one; however, subsect. Flagellares and subsect. Hemi-sphaericae were not recognized as separate entities, and nested within subsect. Gemmiparae; (3) subsect. Hircu-loideae and subsect. Rosulares clustered together as sister subclades while subsect. Gemmiparae diverged early. In addition, our results suggest that the paired variation of ITS sequences in sect. Ciliatae is relatively low between the sampled species in spite of their diverse morphology. It is suggested that such a scenario may mirror rapid speciation in this section that probably trigged by the uplifts of the Qinghai-Tibetan Plateau and the extensive selection pressure under the alpine environments.     

Strong nuclear differentiation contrasts with widespread sharing of plastid DNA haplotypes across taxa in European purple saxifrages (Saxifraga section Porphyrion subsection Oppositifoliae)

The purple saxifrages, Saxifraga section Porphyrion subsection Oppositifoliae, comprise the closest relatives of the arctic–alpine model plant S. oppositifolia and have a centre of diversity in the central and southern European mountain ranges. Many taxa have been described and taxonomic concepts vary among different treatments. Using amplified fragment length polymorphism (AFLP) fingerprinting, we show that some taxa form strongly supported genetic entities best recognized at the species level (S. biflora, S. blepharophylla, S. retusa, S. rudolphiana and S. speciosa), whereas others (S. murithiana and S. paradoxa) are not genetically divergent at all. Saxifraga oppositifolia s.s. is phylogenetically incoherent. Plastid DNA sequence data show limited congruence with the predominantly nuclear‐derived AFLPs. Several co‐distributed taxa (S. biflora, S. blepharophylla, S. oppositifolia s.s. and S. retusa) share the same set of haplotypes. In the widespread S. oppositifolia and S. retusa, highly divergent haplotype lineages were discovered which exhibit a geographical rather than taxonomic structure. Recent and ancient hybridization and/or lineage sorting are probably responsible for the strong incongruence between data derived from nuclear and plastid genomes. Hybridization, which is known to occur among almost all taxa of this group when growing in sympatry, however, seems to be insufficient to break down species barriers. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 173 , 622–636.