A Study on Pollen Morphology of Some Chinese Genera in Tribe Anthemideae

This paper deals with pollen grains of 9 chinese genera of Trib. Anthemideae Cass., which include the genera: Ajania Poljak., Hippolytia Poljak., Stilpnolepis Krasch., Elachanthemum Ling et Y. R. Ling, Filifolium Kitam., Ajaniopsis Shih, Kaschgaria Poljak., Neopallasia Poljak., Seriphidium Poljak., Pollen grains of these genera are isopolar, radially symmetrical, 3-colporate, NPC 345, spheroidal, sometimes suboblate or subprolate. Polar axis 20.0-30.0μm equatorial axis 20.0 -30.0μm. The exine consists of three layers: tectum, columellae and nexine. Exine thickness 3.2-5.6μm, usually the columellae is the thickest. According to the differences of exine ornamentation, they are divided into two main groups: 1. with distinct spines, including the genera Ajania Poljak., Hippolytia Poljak., Stilpnolepis Krasch., 2.with indistinct spinules, including the genera Elachanthemum Ling et Y.R.Ling, Filifolium Kitam., Ajaniopsis Shih, Kaschgaria., Neopallasia Poljak.,Seriphidium Polj     

紊蒿属一新种和对该属分类及演化的讨论

对新种多头紊蒿(Elachanthemum polycephalum Z.Y.Zhu et C.Z.Liang)的形态特征进行了描述,并从形态和生态特征、地理分布及其区系起源等方面探讨了紊蒿属(Elachanthemum Y.Ling et Y.R.Ling)的分类地位。结果表明：紊蒿属与百花蒿属(Stilpnolepis Krasch.)在形态上虽有相近之处,但花、果实和花粉等形态差异明显,因而不能并入百花蒿属,而应独立成属。该属起源于第三纪亚洲北部的古蒿类群(Pro-Artemisia L.),是蒿类中较为原始的属,为古地中海东部残遗的旱生成分,也是现代亚洲中部荒漠(戈壁荒漠)的持有属;多头紊蒿新种的发现,使紊蒿属从单种属变成寡种(双种)属,表明荒漠植物区系的物种分化仍在进行。     

蒿属与邻近属的谱系分支分析

本文首次报道“蒿属与邻近属的谱系分支分析”,结果如下:在蒿自然群中,蒿属和绢蒿属及线叶菊属和栉叶蒿属各为一对姐妹群,后一对姐妹群还与毛蒿自然群有较近的亲缘关系;紊蒿属和百花蒿属在进化过程中,作为两个独立的属,很早就与蒿自然群其它属分化出。在蒿属各组中,腺毛蒿组和白苞蒿组为一对姐妹群,并与艾组构成姐妹关系;龙蒿亚属三个组(龙蒿组、牡蒿组和球蒿组)的亲缘关系很接近,且与友蒿组有较近的亲缘关系。 研究的结果支持林有润的蒿属与蒿自然群的演化假说和紊蒿作为一个独立的属的观点以及将中国蒿属分为蒿亚属和龙蒿亚属以及七个组的观点。根据谱系分支分析的结果以及形态上的特征,建议在蒿属下建立一新亚属,灰蒿亚属。     

Taxonomy of the Genus Oreocharis (Gesneriaceae)

The genus Oreocharis as circumscribed here consists of 27 species including 5 varieties, of which 5 species and 4 varieties are described as new in the present paper. In the work analysed were the external morphology and geographic distribution and examined under SEM were pollen exine of 22 species and seed coat of 16 species. As a result, three types of the corolla, two types of the anther, three types of the pollen exine and three types of the seed coat are distinguished here in the paper. It is discovered that the corolla in the genus is relatively stable, though diverse, and highly correlated with the characters of pollen grains and seeds. The corolla clearly bilabiate but constricted at the throat, occurring in O. auricula, O. cordatula, O. aurantiaca, etc., for an example, is correlated with smooth, reticulate pollen exine and partial tectum and the reticulate and smooth seed coat. For this reason the subdivision of the genus in the paper is mainly based on the characters of the corolla, but combined with those of the anther, pollen and seed coat. The genus is divided into four sections in the present classification. Dasydesmus Craib, based on a single species. O. bodinieri, is reduced here, and the reasons are given. The genus is distributed mainly in the subtropics, and less frequently in the tropics, of China south of 32.5°N and east of 98.5°E, with only two species beyond the border, O. hirsuta in Thailand (only a single locality in Chiengmai) and O. aurea also found in north Vietnam (see Fig. 1, Table 3). Sect. 1. Stomactin (Clarke) Fritsch. Corolla urceolate-tubular, constricted at the throat, with limb distinctly bilabiate; anthers broad-oblong; seed coat reticulate, smooth, rarely minutely tuberculate; pollen exine fine-reticulate, tectum partial and smooth, luminae slightly unequal in size. Sect. 2. Orthanthera K. Y. Pan Corolla campanulate or campanulate-tubular; anthers broad-oblong; seed coat reticulate, muri smooth, rarely spiny-processed; pollen exine fine-reticulate, with partial and smooth tectum and luminae slightly unequal in size, rarely exine insular and fine-tuberculate, tectum perforate. Setc. 3. Oreocharis Corolla thin-tubular; anthers broad-oblong; seed coat densely spinyprocessed, rarely fine-tuberculate; pollen exine insular, densely spiny-processed, rarely finereticulate and smooth, luminae unequal in size. Sect. 4. Platyanthera K. Y. Pan Corolla campanulate; anthers hippocrepiform; seed coat densely spiny-processed; pollen exine fine-reticulate, tectum perforate, luminae small, nearly equal in size. In the section Stomactin, although the constriction of corolla at its throat is a specialized character, the characters of seed coat, pollen grains and anthers are apparently primitive. Therefore it may be said at least that more primitive characters are preserved in the section. In the section Oreocharis, on the contrary, the characters of corolla, seed coat and pollen exine are all advanced. And in the section Platyanthera, the seed coat, pollen (with perforate tectum) and anthers have developed rather specialized characters.     

菊科裸苑属的分类研究

裸菀属Miyamayomena Kitam.是北村四郎¹⁾(1937)从马兰属Kali-meris Cass.(Asteromaea B1.)分出的一个小属,隶属于菊科紫菀族Trib.Astereae Cass.紫菀亚族Asterinae O.Hoffm,本属发表时,曾取名为Gymnatser Kitam。主要以瘦果顶端具狭环状边缘而无冠毛,与具糙毛状或膜片状短冠毛的马兰属相区别。     

川西毛冠菊的名实问题

在观察大量标本和野外考察的基础上,认为Nannoglottis souliei (Franch．)Ling et Y．L. Chen应作为N．gynura (C．Winkl．)Ling et Y．L. Chen的异名。     

石蝴蝶属一新种——黄斑石蝴蝶

描述了苦苣苔科（Gesneriaceae）石蝴蝶属(Petrocosmea Oliv.)一新种——黄斑石蝴蝶(P.xanthomaculata G.Q.Gou et X.Y.Wang)。新种与贵州石蝴蝶（P.cavaleriei Lévl.）相近,但叶多数,20～40枚,叶基心形,花冠白色,在裂片之间具明显黄色斑纹,苞片小,长约1 mm,花柱除上部外密被开展的白色长柔毛而不同。     

Euphrasia brevilabris Y. F. Wang,Y. S. Lian & G. Z. Du,a new species of the Scrophulariaceae from the Qinghai-Tibetan Plateau,China

Euphrasia brevilabris Y. F. Wang, Y. S. Lian & G. Z. Du, a new species of the Scrophulariaceae from Gannan grassland of Gansu belonging to the east edge of the Qinghai-Tibetan Plateau of China, is described and illustrated. It is related to E. regelii Wettst. by having dense tentacle on the leaves, bracts and calyces, but differs from plant shorter, 3–7 cm high, without ramification, leaves smaller, 3–5 mm long, corolla yellow, the back 3–5 mm long, and labium shorter than muffle. It is also similar to E. pectinata Ten. by bracts obviously bigger than vegetative leaves, but differs from plant shorter, leaves smaller, having dense tentacle on the leaves, bracts and calyces, corolla yellow, labium shorter than muffle.     

Saussurea pseudograminea sp. nov. (Asteraceae) from the Qinghai–Tibetan plateau,China

Morphological characteristics, as well as ultrastructure of pollen grains, chromosome numbers and karyotype analysis have been used to establish a new species of Saussurea from the Qinghai–Tibetan plateau. The new species, Saussurea pseudograminea Y. F. Wang, G. Z. Du et Y. S. Lian is easily distinguished from the similar S. graminea Dunn by having 2–3 capitula, involucre 0.7–1.2 cm in diameter, smaller pollen grains, pollen surface with larger and denser spines, achenes 4.0–5.5 mm long, 32 chromosomes, and a karyotype formula 2n = 2x = 32 = 18m + 10sm + 4st, whereas S. graminea has solitary capitula, involucre 1.2–2.0 cm in diameter, larger pollen grains, pollen surface with smaller and sparser spines, achenes 3–4 mm long, 28 chromosomes and a karyotype formula 2n = 2x = 28 = 6m + 20sm + 2st. The new species is distributed in Dianzhangou, Awanchang, and Gamaliang mountain regions of Maqu county in Gansu province.     

中国大蒜芥族植物花粉形态的研究

对中国大蒜芥族10属14种植物花粉形态分别进行了光镜和扫描电镜下的观察研究。结果表明该族花粉形态可划分为4种类型：（1）具3沟,超长球形,网状纹饰,外壁2层;（2）具3沟,超长球形,细网状纹饰,外壁1层;（3）具3沟（偶4沟）,长球形,网状纹饰,外壁2层;（4）具6沟,长球形,网状纹饰,外壁2层。因此,中国大蒜芥族的花粉形态多样性程度较高,说明了它不是一个自然类群,是一个多系类群,这与前人研究结果相一致。另外,本文首次报道十字花科锥果芥属植物具6沟花粉,具6沟花粉在十字花科中极为特殊,所以作者将锥果芥属提升为族级,另立新族,即锥果芥族（Tribe Berteroelleae F．Z．Li,G．Y．Tang ＆ Z．Y．Sun,trib．nov．）。     

Pollen morphology in relation to floral types and pollination syndromes in Pedicularis (Orobanchaceae)

Floral diversification in the genus Pedicularis (Orobanchaceae) is remarkable among flowering plants. In this genus, floral morphology and pollinator behavior are closely co-adaptive. In the current paper, pollen grains of 23 representative species of Pedicularis mainly from North America, with two species from Japan and two species from China, whose pollination ecology was previously studied, were examined using light microscopy and scanning electron microscopy. Two pollen aperture types and three kinds of exine ornamentation were recognized among these species. In addition, pollen data from previous and the current studies of Pedicularis were integrated and analyzed, together with some pollination characters. There was a significant association between pollen aperture types and corolla types, as well as between pollination syndromes and corolla types. However, there was no association of exine ornamentations with corolla types. The relationships and evolution of this genus were discussed with regards to pollen morphology, corolla types and pollination syndromes.     

稠李属(Padus Mill.)花粉形态研究

首次报道中国稠李属花粉形态研究,结果表明:花粉粒形态、大小和外壁纹饰可作为划分种的依据。由此可区分为:花粉粒32.0×25.5μm、条纹细弯、穿孔明显的是亚洲稠李(P.asiatica Kom.);花粉粒37.5×17.7μm、体积大、穿孔多的是光叶亚洲稠李(var.subglabra Y.L.Hanet C.Y.Yang var.nov.);花粉粒32.0×24.4μm、条纹细直、穿孔少量的是欧洲稠李(P.aviummill.);花粉粒21.0×22.1μm、条纹宽、直、穿孔不明显,即北京稠李(P.beijingensis Y.L.Hanet C.Y.Yang sp.nov.),(新种已另文发表)。     

Multifunctional bracts enhance plant fitness during flowering and seed development in Rheum nobile (Polygonaceae), a giant herb endemic to the high Himalayas

Specialized bracts are thought to be important for the successful reproduction of some plants and are regarded as adaptations to diverse driving forces. However, few empirical studies have quantified the adaptive significance of bracts within a cost–benefit framework. We explored the adaptive significance of large and showy bracts for reproduction in Rheum nobile, a giant herb endemic to the high Himalayas. We examined whether the bracts enhance reproductive success during flowering and seed development. Bracts increased flower and fruit temperature on sunny days, greatly decreased the intensity of ultraviolet-B (UV-B) radiation reaching flowers and fruits, and prevented pollen grains being washed away by rain. Experiments indicated that high temperature could promote pollen germination, while pollen grains exposed to rain and UV-B radiation at ambient levels were seriously damaged. Furthermore, bract removal decreased the number of pollinators visiting flowers. When bracts were removed before or after flowering, fecundity and progeny quality were adversely affected, but seed predation by larvae of pollinators decreased. A cost–benefit analysis demonstrated that the cost of bracts, i.e., increased seed predation, is modest. Our results suggest that the bracts of R. nobile promote pollen germination, protect pollen grains from rain and intense UV-B radiation, enhance pollinator visitation during flowering, and facilitate the development of fertilized ovules during seed development. We conclude that multifunctional bracts of R. nobile are an effective adaptive strategy in alpine environments and might have been selected for because of abiotic environmental conditions as well as for enhancing pollination success.     

Pollen morphology in the genus Veronica L. (Plantaginaceae) and its systematic significance

Pollen grains of 30, mainly annual, species from 134 populations of the genus Veronica (Plantaginaceae, formerly Scrophulariaceae) from the Mediterranean Region, have been studied with light and scanning electron microscopy. Three pollen types are defined based on pollen size and exine surface sculpture. In some cases within the study group pollen size can be useful in species determination. Hypothetical relationships of pollen grain size and aperture number with ploidy level, style length and corolla diameter are discussed. The ornamentation of the exine in Veronica, although generally a conservative character within the genus, gives some additional support to the most recent infrageneric classification of Veronica.     

Revision of Lactuca L. and Two New Genera of Tribe Lactuceae (Compositae) on the Mainland of Asia (Cont.)

Having mixed extremely various patterns of achenes for a long time in the genus Lactuca L., especially showed in the classification of it on the mainland of Asia, Lactuca L., the primary unnatural genus, becomes more nuclear in its limit. The present paper makes a revision to attempt providing a clear cline between Lactuca L. and its relative genera. On my opinion, only plants, represented by Lactuca sativa L., which have ovoid capitulum during its fruiting, numerous (7-25), yellow ligular florets and longitudinal 1-10 ribs or striae on each side of achenes, acute into filiform beak at its apex, should be defined as Lactuca L. In view of the present concept of Lactuca L., another group of plants, embodied by Lactuca indica L., having its broadening, thin winged-margin of, 1-3 striae on each side of achenes, black, dorsi-ventral compressed, acute into thick and short beak at its apex, evidently, should not be placed into Lactuca L., but be regarded as genus, i.e. Pterocypsela Shih, gen. nov. Pterocypsela Shih distributes in Eastern and southern Asia, where Lactuca L. does not occur. In China there is all of species, seven species, of Pterocypsela Shih. They are P. raddeana (Maxim.) Shih, P. indica (L.) Shih, P. elata (Hemsl.) Shih P. lacciniata (Houtt.) Shih, P. triangulata (Maxim.) Shih, P. sonchus (Lévl.) Shih and P. formosana (Maxim.) Shih, But in Mediterranean regions and Middle and Western Asia mainly distributes Lactu ca L., in which there are only seven species from western China, Xijiang autonomic district. They are L. dolichophylla Kitam., L. sativa L., L. altaica Fisch. et Mey., L. serriola Torner, L. dissecta Don, L. auriculata DC. and L. undulata Ledb. With the combination of violet-purple ligular florets non-ovoid capitulum during its fruiting, a little thick achenes, acuminate into longer. or short beak at its apex and 4-6 ribs on each side of it, Mulgedium tataricum (L.) DC. is evidently different from Lactuca sativa L. with combination of ovoid capitulum during its fruiting, yellow ligular florets and compres sed achenes, acute into filiform beak at its apex. There seems to be no point in refusing Mu lgedium Cass. as a genus. Strictly speak, Mulgedium Cass. seems to be reminiscent of Para prenanthes Chang (see bellow) without beak at the apex of its achenes. In Hengduan moun tains and mountain range of Himalayas M. tataricum (L.) DC. discoveries its relative par tners. They are M. bracteatum (Mook. f. ex. C. B. Clarke) Shih, M. lessertianum (Wall. ex C. B. Clarke) DC., M. monocephalum (Chang) Shih, M. umbrosum (Dunn) Shih, M. meridionale Shih and M. polypodifolium (Franch.) Shih. Having broadering and thickening margin and 4-7 striae on each side of achenes, grey, dorsi-ventral compressed, truncate and beakless at its apex, Lactuca sibirica (L.) Benth. ex Maxim. (Sonchus sibiricus L.) is not only different from Lactuca sativa L. with the combination of yellow ligular florets and filiform beak at apex of its achenes, but also from the genus Mulgedium Cass. with beak at apex of its achenes. Therefore, Lagedium Sojak, established by J. Sojak (1961), should be restored. It should be point out that Lagedium Sojak is monotypic genus excluding Mulgedium tataricum (L.) DC. with beak at the apex of its achenes, non-marginated. Lagedium Sojak widely distributes in temperate and frigid zone ofvnorthern hemisphere. In our country, Lagedium sibiricum (L.) Sojak, sole species of the genus, restricts its northeast region. Paraprenanthes Chang, the new genus, established by Ch. Ch. Chang (1950) based on Lactuca sororia Miq. and Lactuca yunnanensis Franch. seems to be a distinct genus. This genus is characterized by 4-6 ribs on each side of achenes, black, fusiform, a little thick and beakless at its apex. Besides above-mentioned two species, assigned by Chang, in forest of tropic and subtropic zones on the mainland of Asia there are many species with same structure in achenes like L. sororia Miq. and L. yunnanensis Franch. The genus Paraprenanthes Chang seems to be reminiscants of Mulgedium Cass. and Lagedium Sojak, but differs from the former in its beakless achenes, from the later in its non-marginated achenes and 4-6 ribs on each side of it. In our country, there are all species of the genus known in the tropic and subtropic zones on the mainland of Asia. They are P. sororia (Miq.) Shih, P. yunnanensis (Franch.) Shih, P. longiloba Ling et Shih, sp. nov., P. heptontha Shih et D. J. Liou, sp. nov., P. prenanthoides (Hemsl.) Shih, P. pilipes (Migo) Shih, P. thirionii (Lévl.) Shih, P. sylvicola Shih., sp. nov., P. multiformis Shih, sp. nov., P. auriculiformis Shih, sp. nov. and P. sagittiformis Shih, sp. nov.     

The development of pistillate and perfect florets in Xeranthemum squarrosum (Asteraceae)

The formation of capitulum inflorescence with two different types of floret is an interesting issue in floral biology and evolution. Here we studied the inflorescence, floral ontogeny and development of the everlasting herb, Xeranthemum squarrosum, using epi‐illumination microscopy. The small vegetative apex enlarged and produced involucral bracts with helical phyllotaxy, which subtended floret primordia in the innermost whorl. Initiation of floret primordia was followed by an acropetal sequence, except for pistillate peripheral florets. The origin of receptacular bracts was unusual, as they derived from the floral primordia rather than the receptacular surface. The order of whorl initiation in both disc and pistillate flowers included corolla, androecium and finally calyx, together with the gynoecium. The inception of sepals and stamens occurred in unidirectional order starting from the abaxial side, whereas petals incepted unidirectionally from the adaxial or abaxial side. Substantial differences were observed in flower structure and the development between pistillate and perfect florets. Pistillate florets presented a zygomorphic floral primordium, tetramerous corolla and androecium and two sepal lobes. In these florets, two sepal lobes and four stamen primordia stopped growing, and the ovary developed neither an ovule nor a typical stigma. The results suggest that peripheral pistillate florets in X. squarrosum, which has a bilabiate corolla, could be considered as an intermediate state between ancestral bilabiate florets and the derived ray florets.     

蜘蛛抱蛋亚族的花粉形态

本文研究并报道了百合科蜘蛛抱蛋亚族的花粉形态,主要结论如下：1．开口箭属含两种花粉类型即：(1)单槽、椭圆形;(2)无萌发孔、球形。具单槽、椭圆形花粉的种类含单型性核型,花形较小,柱头小而花柱短,雄蕊高于柱头;无萌发孔、球形花粉的种类则为单型性核型,花形较大,柱头常高度膨大,雄蕊常着生在花被筒基部。2．万年青属花粉为椭圆形,具单槽;蜘蛛抱蛋属花粉则为球形,无萌发孔;开口箭属花粉一部分与万年青属相似,另一部分则与蜘蛛抱蛋属雷同。3．蜘蛛抱蛋亚族中最原始的花粉类型为单槽椭圆形,具孔状或网状外壁纹饰。球形,无萌发孔,外壁具皱波状、瘤状或芽孢状纹饰的花粉为派生类型。4．蜘蛛抱蛋亚族种下花粉形状、萌发孔类型和外壁纹饰基本稳定,可作为分种特征。     

Pollen Morphology of the Genus Nomocharis and Its Delimitation with Lilium

In this work examined were pollen grains of 6 species of Nomocharis and 4 species of Lilium, all under LM and SEM, but Nomocharis saluenensis Balf. f. under TEM. The pollen grains are monocolpate (distal) in Nomocharis, monocolpate or 2-3-porate in the species of Lilium examined. Two types of pollen grains in Nomocharis are recognized based upon the exine stratification and sculpture. The pollen characters and gross morphology, and their evolutionary trends in both Nomocharis and Lilium are discussed. Our conclusions are as follows: 1. Lilium henrici Franch. 、L. souliei (Franch.) Sealy 、L. lophophorum (Bur. et Franch.) Franch. and L. nanum Klotz. et Garcke differ from Nomocharis in the aperture and sculpturing elements. Their pollen morphology supports their being placed in Lilium. 2. The pollen grains of both Lilium lophophorum (Bur. et Franch.) Franch. and L. nanum aggregate are monocolpate or 2-3-porate, which shows an evolutionary trend of aperture from monocolpate to porate, as suggested by Walker and others [Walker et al., (1975), and Chanda (1979)]. 3. In Balfour’s (1918) classification system of Nomocharis, N. pardanthina Franch. and N. meleagrina Franch. belong to Sect. Nomocharis, while N. forrestii and N. biluoensis are placed in Sect. Ecristata, but their pollen grains are all reticulate. They refer to type I (see Table 2). Thus, it does not seem reasonable placing in a single section, Sect. Ecristata, N. forrestii and N. biluoensis with the reticulate exine and N. saluenensis and N. aperta with the two-row-ritipilate exine. 4. Nomocharis saluenensis Balf. f. differs from Lilium in the exine sculpture, which seems to support placing it in Nomocharis. 5. Muri of N. forrestii Balf f. and N. biluoensis s.y. Liang show a tendency of connecting each other by heads of pili, and these two species are intergraded with the other species of the type I with respect to gross morphorlogical characters. It is thus considered that the reticulate pollen grains in Nomocharis is derived from ritipilate ones. This opinion is also held by Nair (1965). 6. Nomocharis differs from Lilium in the exine ornamentation, but some species of Nomocharis are very similar to Lilium in the gross morphology. It shows the close affinity between Nomocharis and Lilium.     

7种绢蒿属植物染色体数目和核型研究

首次报道了中国绢蒿属[Seriphidium (Bess.) Poljak.]7种植物的染色体数目和核型,其核型公式分别为:西北绢蒿[S.nitrosum (Web.ex Stechm.) Poljak.]2n=2x=18=6m(2SAT)+8sm +2st+2T;沙漠绢蒿[S.santolinum (Schrenk) Poljak.]2n=2x=18=14m+4sm;博洛塔绢蒿[S.borotalense (Poljak.) Ling et Y.R.Ling]2n=2x=18=2M+14m+2sm;新疆绢蒿[S.kaschgaricum (Krasch.) Poljak.]2n=2x=18=8m(2SAT)+10sm(2SAT);纤细绢蒿[S.gracilescens (Krasch.et Iljin) Poljak.]2n=2x=18=4m+14sm(2SAT);三裂叶绢蒿[S.junceum (Kar.et Kir.) Poljak.]2n=2x=18=10m+4sm+4st;民勤绢蒿[S.minchünensa Y.R.Ling]2n=2x=18=12m+6sm.结果表明,7种绢蒿植物中,博洛塔绢蒿最原始,西北绢蒿最进化.