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1.
Pertya multiflora Cai F. Zhang & T. G. Gao (Asteraceae, Pertyeae) sp. nov. from Zhejiang Province of China is described and illustrated. It is similar to P. pubescens and P. pungens which all have leaves with small spherical glassy tawny glands, but differ by narrowly ovate to nearly elliptic leaves, capitula solitary or in pairs on terminal branches, capitula with 20–30 florets and 9–12‐seriate involucres. Information on phenology, distribution and ecology of P. multiflora is presented, along with a conservation assessment as Critically Endangered (CR) using the IUCN red list criteria. A key to the known species of Pertya in southeast China is provided.  相似文献   

2.
Aletris simpliciflora R. Li & S. D. Zhang, a new species of Nartheciaceae from southwest Xizang, China, is described and illustrated. It is similar, and apparently closely related, to A. nana S. C. Chen, but differs by having usually solitary flower, pubescent bract and bracteole, and distinct filaments ca 1.2 mm long.  相似文献   

3.
Symplocos parvibracteata sp. nov. (Symplocaceae) from Chemunji Hills, south Western Ghats, Kerala State, India, is described and illustrated. It is most similar to S. wynadensis and S. tenella, a putative synonym of S. wynadensis, but differs in having shorter racemes, shorter bracts and bracteoles that are persistent in flower and caducous in fruit, narrowly ellipsoid flower buds, and fewer stamens per flower. It is also similar to S. sumuntia, from which it differs by its pubescent branchlets, generally more stamens per flower, and a pubescent floral disk, and to S. macrophylla, from which it differs by the combination of 3 to 5 leaf secondary veins on each side of the midvein, 1–2‐cm long inflorescences, and bracts that are persistent in flower, caducous in fruit, and < 1.5 mm long.  相似文献   

4.
Primulina maciejewskii F. Wen, R.L. Zhang & A.Q. Dong, a new species of Primulina (Gesneriaceae) from Guangdong, China, is described and illustrated. It is similar to P. lobulata and P. danxiaensis in leaf and flower shape, but can be distinguished by bract shape, peduncle, pedicel, and bract size, filament and anther indumentum, and number of bracts, staminodes and stigma.  相似文献   

5.
A new species of Gesneriaceae, Raphiocarpus tamdaoensis V. X. Phuong, D. T. Xuyen & Y. G. Wei, is described and illustrated from Vietnam. It is similar to R. asper (Drake) B. L. Burtt and R. evrardii (Pellegr.) B. L. Burtt, but is easily differentiated by leaf blades being ovate–elliptic or obovate, 4–10 × 1.5–3.5 cm, one cyme with only one flower, peduncle linear, 3.0–5.0 cm long, corolla light yellow, 3.0–4.5 cm long, and a pubescent ovary.  相似文献   

6.
Flowers of Peperomia species are the simplest structurally of any of the members of the Piperaceae. The spicate inflorescences form terminally and in axillary position; in each, the apex first is zonate in configuration with a two-layered tunica while 3-4 leaves are initiated. Later, when the inflorescence apical meristem begins bract initiation, the biseriate tunica persists, but zonal distinctions diminish and the apex can be described in terms of a simple tunicacorpus configuration. The inflorescence apex aborts after producing 30-40 bracts in acropetal succession an abscission layer forms across the base of the apex, and the meristem dries and drops off. Bracts are produced by periclinal divisions in T2 (and occasionally also in the third layer as well); the later-formed floral apices arise by periclinal divisions in T2 and the third layer. Each floral apex is at first a long transverse ridge in the axil, perpendicular to the long axis of the inflorescence. This establishes bilateral symmetry in the flower, which persists throughout subsequent growth. The floral meristem becomes saddle-shaped, and two stamen primordia are delimited, one at either end and lower than the central floral apex. A solitary carpel is initiated abaxially, and soon forms a circular rim which heightens as a tube with an apical pore. Within the open carpel, a solitary ovule is initiated from the entire remains of the floral apical meristem; it, hence, is terminal in the flower, and its placentation is basal. Carpellary closure in P. metallica results from accelerated growth of the abaxial lip, and the two margins become appressed. Species differ greatly as to whether the abaxial or the adaxial lobe predominates in late stages of carpel development. In P. metallica, the receptive portion of the stigma forms from the shorter lobe which is overtopped. Stigmatoid tissue forms internal to the receptive stigma. The prevailing bilateral floral symmetry, absence of a perianth, and the spicate inflorescence are features which distinguish Peperomia (and Piperaceae) from the magnolialian line of angiosperms.  相似文献   

7.
8.
Floral traits such as color and size are highly diversified in lilies, but their adaptive significance remains uncertain. In the present study, we compared pollination processes between Lilium japonicum var. abeanum and var. japonicum to clarify how the two varieties are adapted to different pollinators. Lilium japonicum var. japonicum is known to be pollinated by moths, and we hypothesized from its flower traits that var. abeanum is pollinated by diurnal insects. Using waterproof digital cameras set to a recording interval of 10–30 s, we recorded flower visitors for 7–9 flowers of var. japonicum and 4–6 flowers of var. abeanum over 24‐h periods. We also recorded the number of versatile (T‐shaped) and rigid (I‐shaped) anthers per flower. For var. abeanum, we observed flowers at 05.00 and 17.00 hours to determine flower opening time and measured the intensity of floral scent using a metal‐oxide semi‐conductor odor sensor. Both diurnal and nocturnal insects visited flowers of the two varieties, but visitation of diurnal insects was more frequent in var. abeanum. Anthers of var. abeanum are usually rigid, as in many bee‐pollinated flowers, whereas those of var. japonicum are mostly versatile. Although flowers of var. japonicum are known to open in the evening, 32% of the flowers of var. abeanum started to flower during the day. Lilium japonicum var. abeanum emitted scent at night, with a maximum intensity at 20.00 hours, just as in var. japonicum. These findings suggest that the floral traits of the two varieties are adapted to the different relative availabilities of nocturnal versus diurnal pollinators. The flower of var. abeanum is more adapted to diurnal pollinators, but retains adaptations to nocturnal pollinators, particularly with regard to its scent.  相似文献   

9.
Theodore Munyuli 《Grana》2013,52(1):69-89
An on-farm pollination experiment was conducted during the June–August and November–February blooming seasons of 2007 to 2008, in 30 small-scale coffee fields characterised by different habitat and vegetation types. The study was conducted in order to determine the best pollinator groups for coffee in Uganda and to collect relevant field information and determine the pollination efficiency of different bee species. Results indicate that across blooming seasons, coffee flowers were visited by 24–36 bee species. Hypotrigona gribodoi was the most frequent flower visitor, comprising over 60% of 5941 bee-visits recorded. Foraging rate and pollination speed varied among bee species. Solitary bees foraged on more flowers than social bees, but they spent less time per flower visited. Solitary bees visited more coffee trees and fields, but deposited less pollen, whereas social bees visited less trees and coffee fields in the landscape, but deposited more pollen on flowers. Fruit set was of 87%, 64% and 0.9%, respectively, in hand-cross pollination, open pollination and controlled-pollination treatments. Fruit abortion due to self-pollination was insignificant in this study. There was variability in pollination efficiency of different bee species. Pollination efficiency varied more significantly with sociality than with other bee functional traits and was not significantly influenced by tongue length and bee body size. Single-flower visits by social and solitary bees resulted in 89.7% and 68.14% fruit set, respectively. The most efficient bee species was Meliponula ferruginea (98.3%) followed by Meliponula nebulata (97.1%). Thus, very good pollinator species were wild social bees (mainly stingless bees) as opposed to honeybees and solitary bees that were previously reported to be the best pollinators of coffee in Panama and Indonesia. Morphological and anatomical characteristics of the bee pollen storage features may explain the difference in foraging behaviour activities and in pollination efficiency of social and solitary afrotropical bee species visiting lowland coffee in Uganda. In addition, pollination efficiency was influenced by land-use intensity, field management systems and habitat types found in the immediate surroundings of coffee fields, but not by coffee field size, coffee genotypes and mass blooming wild vegetation. It is recommended to farmers to adopt pollinator-friendly conservation and farming practices such as keeping an uncultivated portion (25%–30%) of their farms as pollinator reservoirs, protecting semi-natural habitats found in the vicinity of coffee fields, as well as promoting high on-farm tree cover to benefit a functionally diverse pollinator community.  相似文献   

10.
  • Long‐lived flowers increase pollen transfer rates, but these entail high water and carbon maintenance costs. The retention of pollinated and reward‐free old flowers enhances pollinator visitation to young receptive flowers by increasing floral display size. This mechanism is associated with acropetal inflorescences or changes in flower colour and openness, but the retention of unchanging solitary flowers remains overlooked.
  • We examined pollination‐dependent variation in floral longevity and determined stigmatic receptivity, pollen viability and pollen removal rates among flower ages in Kielmeyera regalis, a Neotropical savanna shrub. We also evaluated the effects of floral display size on pollinator visitation rates. Lastly, we determined whether old flowers are unvisited and exclusively increase pollinator attraction to young flowers through flower removal experiments.
  • Regardless of pollination treatment, flowers lasted fully open with no detectable physical changes for 3 days. Over time, stigmas remained receptive but >95% of pollen was removed. Pollinator visitation significantly increased with floral display size and intermediate percentages (15–30%) of newly opened flowers. Accordingly, the retention of reward‐free and unvisited old flowers increased young flower–pollinator interaction.
  • Our results reveal the importance of a prolonged floral longevity in increasing pollinator attraction toward newly opened receptive flowers without changes in flower colour and form. We conclude that the retention of pollinated, reward‐free and unvisited colour‐unchanged old flowers in K. regalis is a strategy that counteracts the water use costs associated with the maintenance of large flowers with increased mate opportunities in a pollen‐limited scenario.
  相似文献   

11.
Photinia taishunensis G. H. Xia, L. H. Lou & S. H. Jin (Rosaceae, Spiraeoideae) from Zhejiang, China, is described and illustrated. It has previously been confused with P. lochengensis Yü, but differs in details of habit, leaf size, leaf shape, inflorescence, flower size and pubescence. The pollen grains of P. taishunensis are monads, elliptical with trisulcate apertures, and the exine is rugulose, dotted with sparse punctures.  相似文献   

12.
Argostemma bachmaense, a new species from central Vietnam, is described and illustrated here. The new species is most similar to A. laoticum and A. vietnamicum but can be distinguished from the latter two by having a well-developed internode with leaf pairs separately arranged along stem, isophyllous or slightly anisophyllous leaves, an oblanceolate to spatulate lamina with attenuate base and lateral veins with 4–5 pairs prominent on abaxially, a terminal, solitary flower, an absent bract, narrowly ovate or broadly lanceolate, 8.5–10.5 × 2.8–4.2 mm petals, 6.5–7.5 mm long stamen with yellow anther, a 8.5–9.5 mm long, exerted style and a globose stigma. Information on ecology, phenology and preliminary conservation assessment of the proposed new species are provided. In addition, we also provide an identification key to the nine Argostemma species found in Vietnam.  相似文献   

13.
The fungus Monilinia vaccinii-corymbosi infects blueberry flowers via the stigma-style ovary pathway to cause mummy berry disease. Previous laboratory experiments documented considerable activity of stigma-applied biofungicides containing the bacteria Bacillus subtilis and, to a lesser extent, Pseudomonas fluorescens against flower infection by the pathogen. However, adequate and targeted delivery of the biocontrol agents to the stigmatic surfaces of open flowers in the field has remained problematic. Here we consider the application of the biofungicides Serenade AS (containing B. subtilis QST713) and BlightBan A506 (containing P. fluorescens A506) to blueberry flowers by air-assisted electrostatic spraying. In laboratory experiments with typical field-use rates, viability of B. subtilis and P. fluorescens was unaffected by different levels of induction-charging voltage (0–1.2 kV) and atomizing pressure (138–276 kPa) applied to an electrostatic spray-charging nozzle, showing that the bacteria in both formulations readily survived exposure to the intense electrical fields and near-sonic atomizing air shear encountered during electrostatic spraying. Electrostatically charged application significantly (P<0.0001) increased deposition of B. subtilis on the stigmatic surfaces of detached blueberry flower clusters by a factor of 4.5 compared with conventional hydraulic spraying; a similar comparison showed that population densities of P. fluorescens on the stigma were increased by a factor of 2.9, but this effect was not statistically significant (P=0.1487). For Serenade, the increased coverage and/or retention on the flower stigma, along with the excellent bacterial survival, portend well for electrostatic application for mummy berry disease control in the field.  相似文献   

14.
Aristolochia bidoupensis Do sp. nov. is newly described. This new species, currently only known from southern Vietnam, is most similar to Aristolochia faviogonzalezii (northern Vietnam) and A. moupinensis (China), but can be distinguished from the latter two by the following characters: flowers terminal, axillary, solitary, peduncle 1.3–1.5 cm long, bracteole ovate, 3–4 × 2–3 mm, limb discoid‐shaped with three expanded lobes, not revolute, internal surface uniformly dark purple, smooth, throat uniformly golden without dots. Morphological characters such as a 3‐lobed gynostemium and a 3‐lobed limb place the new species in A. subgen. Siphisia.  相似文献   

15.
Gaultheria marronina, a new species from the Hengduan Mountain chain of western Sichuan Province, China, is described and illustrated. This species is similar to G. bryoides P. W. Fritsch & L. H. Zhou from the Gaoligong Mountains in its white fleshy calyx with a maroon capsule but differs in its stem setae 0.34–0.50 mm long, petioles 0.4–0.6 mm long, leaf blades 5.1–6.2 × 2.1–3.1 mm, overwintering flower bud pedicels 0.6–0.8 mm long, calyx lobes 2.2–3.0 mm long, and usually slightly open fruiting calyx, among other characters. The species is known only from two widely separated unprotected populations and is categorized as endangered.  相似文献   

16.
One of the most common types of cactus flower in the southwestern United States is the large, colorful, cup-shaped flower.Echinocereus fasciculatus var.boyce-thompsonii in Arizona is a representative of this class of flowers. Its flowers are visited by three common types of insect visitors: medium-sized bees, small solitary bees, and beetles. All three types of visitors come into contact with the pollen, but only the mediumsized bees regularly touch the stigma in their visitations. The main effective pollinators are therefore the medium-sized bees (Megachile, etc.).Ferocactus wislizenii has a similar floral mechanism and is likewise pollinated mainly by medium-sized bees (Megachile, Lithurge, Diadasia, etc.).Pollination of North American Cacti, 1.  相似文献   

17.
Five genetically controlled flower color morphs in Platystemon californicus tend to occur in distinct geographic regions, suggesting regional selection of morphs. I examined the reproductive biology of P. californicus to determine whether color morphs are subject to selection due to differences in pollinator attractiveness. Plants of P. californicus have a high pollen: ovule ratio and are highly self-incompatible. Solitary bees (Andrenidae and Halictidae) are the most effective pollen vectors, but show inconsistent discrimination among color morphs. Platystemon californicus is unusual among annual self-incompatible plants in that wind is an important pollen vector. As a result of wind pollination, most polymorphic populations show no intermorph seed-set differences. Therefore, the geographic distribution of flower color morphs cannot be explained by differential attractiveness of color morphs to pollinators in different regions. Any selective value of color morphs must be due to linkage of flower color with as yet undetected morphologically or physiologically adaptive characters.  相似文献   

18.
A new species of Primulina (Gesneriaceae) from a limestone area in southern China, P. rubella L.H. Yang & M. Kang, is described and illustrated. The new species has purple‐red flowers and is thus similar to P. lijiangensis, but differs by its petiole, leaf blade, cyme, filament, stigma and ovary. In adition, a molecular phylogenetic reconstruction indicated that P. rubella and P. lijiangensis belong to quite different clades. Instead, P. rubella appears to be closely related to the sympatric P. qingyuanensis, although these two species are obviously differentiated both in terms of flower color and other vegetative and floral characters. The conservation status of P. rubella is assessed as ‘Critically Endangered’ (CR) according to the IUCN red list categories and criteria.  相似文献   

19.
Quality control of ginseng currently is mainly based on ginsenoside analysis, but rarely focuses on the volatile organic components. In the current work, an untargeted metabolomics approach, by headspace solid-phase micro-extraction gas chromatography/mass spectrometry (HS-SPME-GC/MS), was elaborated and further employed to holistically compare the compositional difference of the volatile components simultaneously from 12 Panax herbal medicines, which included P. ginseng (PG), P. quinquefolius (PQ), P. notoginseng (PN), red ginseng (PGR), P. ginseng leaf (PGL), P. quinquefolius leaf (PQL), P. notoginseng leaf (PNL), P. ginseng flower (PGF), P. quinquefolius flower (PQF), P. notoginseng flower (PNF), P. japonicus (PJ), and P. japonicus var. major (PJvm). Chromatographic separation was performed on an HP-5MS elastic quartz capillary column using helium as the carrier gas, enabling good resolution within 1 h. We were able to characterize totally 259 volatile compounds, including 82 terpenes (T), 46 alcohols (Alc), 29 ketones (K), 25 aldehydes (Ald), 21 esters (E), and the others. By analyzing 90 batches of ginseng samples based on the untargeted metabolomics workflows, 236 differential ions were unveiled, and accordingly 36 differential volatile components were discovered. It is the first report that simultaneously compares the compositional difference of volatile components among 12 Panax herbal medicines, and useful information is provided for the quality control of ginseng aside from the well-known ginsenosides.  相似文献   

20.
Phenotypic and genetic variation and correlations among floral traits within and among four Primula species were measured to seek evidence for potential constraints on the independent evolution of floral characters, to examine the relationship between mating system, ploidy level, and sex allocation, and to determine whether some traits are more conservative than others within and across these congeners. We measured mean flower diameter, corolla depth, pollen production, modal pollen grain volume, ovule number per flower, and pollen: ovule ratios for 64 field-collected genotypes from northern Europe. These represented one heterostylous (P. farinosa: 2n = 18) and three homostylous (P. scotica: 2n = 54, P. scahdinavica: 2n = 74, and P. stricta: 2n ~ 126) species. All traits differed significantly among species and among the six taxon/morph categories identified (including three morphs of P. farinosa: pin, thrum, and homostylous). Pollen production per flower was significantly higher (and individual pollen grain volume lower) in the outcrossing P. farinosa than in any of the homostylous species; also, pin morphs produced significantly more pollen per flower than thrums in P. farinosa. Among the homostylous species, there were significant differences in all traits except modal pollen grain volume. Ovule number per flower and flower size were less variable among taxa than pollen production and pollen volume. Within species, there were several strong negative correlations among genets between pairs of traits, but each species exhibited a unique set of inverse relationships. We detected only one significant positive genetic correlation; in P. stricta, ovule number and pollen production per flower were positively correlated among genets. Among species means, two pairs of traits were negatively correlated: mean ovule number per flower vs. flower diameter (but P = 0.0587), and mean pollen production per flower vs. modal pollen grain volume. These negative correlations within and among taxa suggest that there may be intrinsic genetic constraints on the independent evolution of these floral characters, but that these constraints differ among species.  相似文献   

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