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1.
中国大陆天麻属一新分布种——细天麻   总被引:1,自引:0,他引:1  
报道了中国大陆兰科(Orchidaceae)天麻属(Gastrodia)1新记录种——细天麻(Gastrodia gracilis Bl.)。标本采自云南省开远市碑格乡,生于海拔约2 500m的常绿阔叶林下,群落郁闭度较大,林下湿润。标本主要形态学特征为总状花序长约6cm,花排列稀疏,管状,下垂,浅棕色,花被筒顶端5裂,苞片宿存,地下茎小。该种此前记录产于中国台湾及日本。该发现在中国大陆尚属首次,加强了中国云南植物区系与中国台湾以及日本植物区系的联系。  相似文献   

2.
The emesine assassin bug genus Emesopsis is reported from Vietnam for the first time and is briefly diagnosed, and two new species of the genus, E. longipilosa and E. albispinosa, are described. They were collected by beating dead, drooping leaves of the banana, Musa acuminata (Musaceae).  相似文献   

3.
A young Cape Gannet Sula capensis responded to high ambient temperatures in the laboratory by standing, gular fluttering with raised head and open bill, wing drooping, defaecating at a fast rate close to or onto the feet, “paddling”; in the excreta, and increased breathing rate. Standing initially caused a decline in foot temperature which rose with rising ambient temperature. Gular flutter and wing drooping assisted the bird in tolerating heat stress. Reduction in heat‐load occurred when standing on a wet surface, presumably due to evaporative heat loss (of excreta on the feet = urohidrosis) and an enhanced conduction of heat to substrate. Field observations confirmed that young Cape Gannets defaecate onto their feet at high ambient temperatures. This species appears preadapted for this behaviour since it builds a solely guano nest, defaecating onto the rim which is compacted by “paddling”;.  相似文献   

4.
Panicle erectness (PE) is one of the most important traits for high-yielding japonica cultivars. Although several cultivars with PE trait have been developed and released for commercial production in China, there is little information on the inheritance of PE traits in rice. In the present study, 69 widely cultivated japonica cultivars and a double haploid (DH) population derived from a cross between a PE cultivar (Wuyunjing 8) and a drooping panicle cultivar (Nongken 57) were utilized to elucidate the mechanisms of PE formation and to map PE associated genes. Our data suggested that panicle length (PL) and plant height (PH) significantly affected panicle curvature (PC), with shorter PL and PH resulting in smaller PC and consequently more erect. A putative major gene was identified on chromosome 9 by molecular markers and bulk segregant analysis in DH population. In order to finely map the major gene, all simple sequence repeats (SSR) markers on chromosome 9 as well as 100 newly developed sequence-tagged site (STS) markers were used to construct a linkage group for quantitative trait locus (QTL) mapping. A major QTL, qPE9-1, between STS marker H90 and SSR marker RM5652, was detected, and accounted for 41.72% of PC variation with pleiotropic effect on PH and PL. another QTL, qPE9-2, was also found to be adjacent to qPE9-1. In addition, we found that H90, the nearest marker to qPE9-1, used for genotyping 38 cultivars with extremely erect and drooping panicles, segregated in agreement with PC, suggesting the H90 product was possibly part of the qPE9-1 gene or closely related to it. These data demonstrated that H90 could be used for marker-aided selection for the PE trait in breeding and in the cloning of qPE9-1.  相似文献   

5.
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   

6.
Photosynthesis in Drought-Adapted Cassava   总被引:5,自引:0,他引:5  
Calatayud  P.-A.  Llovera  E.  Bois  J.F.  Lamaze  T. 《Photosynthetica》2000,38(1):97-104
After 45 d of limited water supply, cassava (Manihot esculenta Crantz) exhibited pronounced reduction in shoot growth, high leaf fall, and decreased stomatal conductance. However, the water status of the remaining leaves was unaffected. This was combined with an amplified heliotropic response and drooping which minimises radiant energy interception at mid-day, suggesting that leaves are sensitive to high irradiance (I). In well-irrigated plants, CO2-saturated oxygen evolution and net photosynthetic rate (P N) in air were markedly higher (5-fold) in young (expanding) leaves than in mature leaves. Water limitation did not strongly modify CO2-saturated oxygen evolution but it altered P N in air for both types of leaves, although differently. The mature leaves of drought-adapted plants displayed residual rate of P N and deteriorated photosystem 2 (PS2) photochemistry estimated from chlorophyll (Chl) a fluorescence measurements. In young leaves at moderate I, P N was depressed by only 66 % in stressed plants. Moreover, the photochemical quenching of Chl a fluorescence and the quantum efficiency of PS2 photochemistry in young leaves were comparable in both control and stressed plants. In contrast at high I, P N was almost null and marked decreases in the two fluorescence parameters were apparent. Hence the strong heliotropic response and drooping displayed by young leaves under water limitation is an important strategy for avoiding inactivation of P N by high I and therefore for cassava tolerance to drought.  相似文献   

7.
Three new benthic, photosynthetic dinoflagellate species, Prorocentrum norrisianum, Prorocentrum tropicalis, and Prorocentrum reticulatum, from floating detritus and coral rubble of Central America are described from scanning electron micrographs. Species were identified based on shape, size, surface micromorphology, thecal plate ornamentation, and architecture of the periflagellar area and intercalary band. Cells of P. norrisianum are ovate with a cell size of 20–25 μm long and 13–16 μm wide. The theca is delicate, its surface smooth, pores species specific with 95 to 105 pores per valve. Pores are round with a diameter of about 0.1 μm. The periflagellar area is V-shaped, located on the right valve in a shallow depression. It has no ornamentation. The flagellar and auxiliary pores are unequal in size. The intercalary band is smooth. Prorocentrum tropicalis cells are ovoid, 50–55 μm long and 40–45 μm wide in valve view with maximum width behind the middle region, narrow at the anterior end. The periflagellar area, situated in the right valve, is a V-shaped wide triangle with a deeply indented depression; the left valve exhibits a flat ridge. The periflagellar area is unornamented, and the flagellar and auxiliary pores are unequal in size. The valve surface is rugose with evenly distributed valve poroids. Each poroid appears to have a small dome in the center. The intercalary band is rimlike around the cell margin, granulated, and horizontally striated. Prorocentrum reticulatum cells are oblong in valve view; cells are 55–60 μm long and 40–45 μm wide. Thecal surface is reticulated; it is composed of a labyrinth of ridges with alternating depressions that vary in size and shape. Each depression has a narrow, oblong-kidney-shaped opening about 0.6 μm long. The periflagellar area is a deep, V-shaped triangle. The right valve of P. reticulatum is excavated, and contains a large flagellar pore and a smaller auxiliary pore surrounded by a narrow apical collar. The left valve margin exhibits a curved flat ridge. The intercalary band is smooth.  相似文献   

8.
The endangered South Australian glossy black‐cockatoo (Calyptorhynchus lathami halmaturinus Mathews 1912) feeds almost exclusively on the seeds of the drooping sheoak (Allocasuarina verticillata), and shows marked preferences for individual trees. This field study investigated foraging ecology and tree selection through observations of foraging birds and measurements of trees and seed cones. The cockatoos spent the vast majority of their foraging time (94%) handling seed cones, and handling behaviour was highly stereotyped. Handling time per cone was correlated primarily with cone size, while seed intake rate was correlated primarily with seed mass per cone. The cockatoos fed mostly in trees with signs of previous feeding. They tended initially to sample trees with large seeds, and to stay for long feeding bouts in trees with high ratios of seed‐to‐cone mass. As a result of these biases, feeding was concentrated in trees with high seed mass per cone. Preferred trees were also larger, with higher ratios of seed‐to‐cone mass and larger seeds containing more lipid and protein. By feeding from selected trees the cockatoos increased both their seed intake rate and the nutritional quality of the seeds ingested, thereby increasing their energy intake rate by an estimated 28%. They did not discriminate against trees that had re‐grown from basal shoots after fires. Insect larvae were present in some seed cones but the cockatoos did not appear to actively seek them. Males foraged 19% more efficiently than females, resulting in greater daily food intake. The characteristics of individual A. verticillata trees that determined the cockatoos’ feeding rates were also correlated with their distribution on a regional scale. This suggests that the distribution of this endangered cockatoo depends not only on the presence of food trees, but also on their regionally varying feeding profitability.  相似文献   

9.
A new species of Rubiaceae, Spiradiclis glabra, is described and illustrated from China. The species is most similar to S. fusca, but differs by having 5–7 pairs of adaxially unconspicuous secondary veins in the leaves, stipules 2–5 mm long, calyx lobes ovate‐triangular, corollas slightly purple–reddish, tubes 13–15 mm long, inside with a pubescent ring of long hairs at the throat, and stamens near the base in long‐styled form. The conservation status of this new species was assessed as ‘Vulnerable’ (VU) according to IUCN.  相似文献   

10.
Onobrychis dushanbensis Ranjbar, Vitek & Karamian, a new Fabaceae species endemic to Tajikistan, is described and illustrated. The new species belongs to Onobrychis Miller subgen. Sisyrosema (Bunge) Grossheim sect. Hymenobrychis DC. It is closely related to O. chorassanica Bunge and O. seravschanica B. Fedtsch., but is easily distinguished by its purple flowers with darker venation (vs yellowish with purple venation), with wings 9–10 mm long (vs wings 4–5 mm long) and bracts 14–15 mm long (vs bracts 4–5 mm long). The relationships between the new and closely related species are discussed.  相似文献   

11.
Summary Two new nitrite oxidizing bacteria for which the names Nitrococcus mobilis and Nitrospina gracilis are proposed were isolated from the marine environment. Nitrococcus mobilis was cultured from South Pacific waters and it is a large motile coccus with unique tubular cytomembranes. Nitrospina gracilis was isolated from South Atlantic waters and it is a long slender rod which lacks an extensive cytomembrane system. Both are obligate marine organisms and both are obligate chemoautotrophs. The fine structure of these organisms is detailed.Contribution No. 2631 from the Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543.  相似文献   

12.
Three new benthic, sand-dwelling dinqflagellate species, Prorocentrum sabulosum, Prorocentrum scuptile, and Prorocentrum arenarium, from coral rubble are described from scanning electron micrographs. Species were identified based on shape, size, surface micromorphology, ornamentation of thecal plates, and architecture of the periflagellar area and intercalary band. Cells of P. sabulosum are oval with a cell size of 48–50 μm long and 41–48 μm wide. The areolae are round to oval and numerous (332–450 per valve) and range from 1 to 1.6 μm in size. The periflagellar area of P. sabulosum bears a wide V-shaped depression with a flat ridge and lacks ornamentation; it accommodates six pores: one large flagellar pore, an adjacent smaller auxiliary pore, and four pores of unknown function. The flagellar and auxiliary pores are surrounded by a narrow apical collar. The intercalary band of P. sabulosum is smooth. Prorocentrum sculptile cells are broadly oval, 32–37 nm long, and 30–32 μm wide in valve view with a deep-sculptured apical area. The valves are smooth and are marked with shallow depressions (856–975 per valve). Some of these depressions have a small round opening (0.13 μm in diameter). The periflagellar area is V-shaped with a deeply indented depression; it accommodates the two flagella and a thin angled apical plate. The intercalary band is smooth. Prorocentrum arenarium cells are nearly round in valve view 30–32 μm in diameter. Thecal surface is smooth with scattered kidney-shaped valve poroids (65–73 per valve) and marginal poroids (50–57 per valve). Length and width of poroids are 0.62 μm and 0.36 μm, respectively. The periflagellar area is an unornamented, broad triangle into which a large flagellar pore and a smaller auxiliary pore are fitted. Both flagella, longitudinal and transverse, protrude from the flagellar pore. The intercalary band is smooth. The presence of a peduncle-like structure (2–3 μm long) in P. arenarium was observed situated in the flagellar pore.  相似文献   

13.
Lysionotus fengshanensis Yan Liu & D. X. Nong, a new species of Gesneriaceae from Guangxi, China, is described and illustrated. Lysionotus fengshanensis is very similar to L. longipedunculatus (W. T. Wang) W. T. Wang, but differs by the peduncle being 2–4 cm long and purple, corolla campanulate, 2.5–3.0 cm long, 1.5–1.7 cm in diameter at the mouth, filaments slightly geniculate near the middle, apex of filaments with gland and staminodes 3.  相似文献   

14.
Zingiber pseudosquarrosum L. J. Singh & P. Singh sp. nov. (Zingiberaceae) from Andaman and Nicobar Islands, India is described and illustrated and its conservation status is evaluated. This new species seems related to Z. squarrosum Roxb. but can be distinguished by the presence of a small pseudostem, long ligule and petiole, broadly lanceolate leaves with cuneate base, caudate apex and paxillate venation, urceolate or prolate inflorescences, very long underground peduncle, long calyx, very long corolla tube, labellum deep purple red (claret) at centre, orange red (vermillion) at lateral sides with ivory (off white) spots, tip truncate and slightly notched, margin folded back, stamen with short filament, yellow orange anther, light brown ovary, blood red (cinnabar) seeds covered by a white aromatic aril. A key to the species of Zingiber Mill. from the Andaman and Nicobar Islands is also provided.  相似文献   

15.
Two new species, Syzygium humbertii Byng and S. mortonianum Byng, are described from Madagascar. When compared with other Madagascan Syzygium, S. humbertii Byng is characterised by sessile to subsessile leaves, orbicular to oval blades with usually cordate bases and rounded apices, and an obconic hypanthium. Syzygium mortonianum Byng is characterised by relatively long leaves that are typically wrinkled when dried, widely spaced venation, long petioles, and particularly dense capitate inflorescences with many flowers. Both new species are threatened with extinction and known from few contemporary collections.  相似文献   

16.

Occurrence of a new disease, shoot blight was observed afflicting mulberry (Morus spp.) in the southern peninsula of India. The disease initiated as marginal burning or blackening of leaf lamina which later spread across the whole lamina and then to the stems of affected shoots, resulting in the drooping of the entire shoot and complete death of the affected plants. On isolation of the causal organism, a bacterial isolate was found to be associated with the disease symptoms, which was identified as Xanthomonas campestris pv. mori. Scanning electron microscopic (SEM) examination of cross sections of stems revealed the presence of rod-shaped bacteria inside xylem vessels of affected plants. This indicates the vascular translocation and colonization of X. campestris pv. mori which resulted in shoot blight in mulberry.  相似文献   

17.
Onosma maculata Ranjbar & Almasi, a new Boraginaceae species endemic to Iran, is described and illustrated. The new species belongs to Onosma sect. Onosma subsect. Onosma. It is closely related to O. nervosa Riedl, but is easily distinguished by its spotted stem and peduncle (vs no spots), leaves 14–23 cm long (vs leaves 4–12 cm long), pedicel 5–15 mm long (vs pedicel 3–5 mm long), higher density of hairs, and glabrous nutlet (vs villous). Moreover, meiotic chromosome number and behavior were studied in two populations of the new species and it was found to be diploid with 2n = 2x = 16.  相似文献   

18.
Calligonum taklimakanense B. R. Pan & G. M. Shen, a new species of Polygonaceae from Taklimakan Desert, Xinjiang, China, is described and illustrated. It is closely related to C. ebinuricum Ivanova ex Soskov in having similar fruit shape and achenes with two rows of bristles, but differs in straight old branches and slightly coiled achenes without a long beak. Calligonum ebinuricum has tortuous old branches, very coiled achenes, and a 2–4 mm long beak.  相似文献   

19.
Trigonotis jiaochengensis Q. R. Liu & R. Y. Yan, a new species from Shanxi, China, is described and illustrated here. It is similar to T. peduncularis in having multiple diffuse stems, ovate to elliptic leaf blades, scorpioid cyme with only basal bracts and trigonous‐tetrahedral nutlets, but differs in having slender pedicels that are 5.2–18.4 mm long (vs clavate pedicels 1.5–4.8 mm in T. peduncularis), smooth nutlets with a short carpophore and a flat bottom (vs verrucose nutlets with a long carpophore and convex bottom in T. peduncularis). Morphological characters, including pollen and nutlets, with illustrations, diagnostic comparisons and habitat, are presented.  相似文献   

20.
Marine phytoplankton samples containing diatoms of the Chaetoceros socialis group were collected from Thailand, China, Denmark, and Greenland, and cells were isolated into culture for light and electron microscopy and DNA sequencing of D1–D3 of the LSU rDNA. Species of this lineage are characterized by three short and one long setae extending from each cell, the long setae from several cells joining into a common center to form large colonies, which are sometimes visible with the naked eye. Phylogenetic analyses including sequences from other parts of the world revealed segregation into three groups. Most sequences fell into two large clades, one comprising material from cold waters, whereas the other contained material from warmer waters. Strain CCMP 172 from the Strait of Georgia, Washington State, USA, formed a separate group. The warm‐water species included Chinese and Thai material and therefore probably also material from the type locality of C. socialis, Hong Kong. It is characterized by all setae being covered by spines and the setae extending from the valve at some distance from the margin. In the resting spores, both valves are ornamented with spines. The cold‐water material is characterized by three spiny and one mostly smooth long setae, and the setae extend from the valve near the margin. Both valves of the resting spore are smooth. This material is described as C. gelidus sp. nov. C. radians, described from the Baltic in 1894, is considered a synonym of C. socialis. CCMP172 is in many ways intermediate and probably constitutes a separate species. The published evidence on this globally distributed and sometimes bloom‐forming group of species indicates higher species diversity than presently thought.  相似文献   

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