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1.
Four new species of the hyphomycete genera Phaeoramularia viz. Ph. caesalpinae, Pseudocercospora viz., Ps. tiliacearum, Stenella, viz. S. argyreiae and S. grewiae occurring on Caesalpinia bonducella Fleming (Caesalpiniaceae), Grewia sp. (Tiliaceae), Argyrea sp. Lour (Convolvulaceae) and Grewia sp. L. (Tiliaceae), respectively are described and illustrated here. All these fungi were collected from Western Ghats of India.  相似文献   

2.
Pollen morphology of 44 species representing 9 genera of Tiliaceae in China was examined under light microscope, 10 of them were observed with scanning electron microscope. Nine genera involved in this paper are: Colona. Corchoropsis, Corchorus, Excentrodendron, Grewia, Hainannia, Microcos, Tilia and Triumfetta The pollen grains of Tiliaceae are eurypalynous. Based on the aperture type and ornamentation, they may be grouped into four types: (1) The Grewia type, pollen grains tricolporate: Colona, Corchorus, Grewia, Microcos and Triumfetta, (2) The Tilia type, pollen grains brevitricolporate: Hainania and Tilia, (3) The Corchoropsis type, pollen grains triporate, spinate: Corchoropsis, and (4) The Excentrodendron type, pollen grains triporate, reticulate: Exce ntrodendron. The significance of pollen morphology in taxonomy of Tiliaceae is discussed. The palynological data seem to support the separation of Microcos from Grewia and the transfer of Corchoropsis to Sterculiaceae from Tiliaceae.  相似文献   

3.
Three new species of Veronaea, V. ficina on Ficus hispida L. (Moraceae), V. grewiicola on Grewia asiatica L. (Tiliaceae), and V. hippocratiae on Hippocratia arborea Willd. (Celastraceae), collected from forests of Nepal and the Terai belt of North-Eastern Uttar Pradesh, India, are described, illustrated and compared with related taxa.  相似文献   

4.
Detailed analyses of karyology and leaf morphology do not support relationships betweenFlacourtiaceae andTiliaceae. In spite of different chromosome numbers,Prockia (2n = 18),Flacourtia (2n = 22) andRawsonia (2n = 22) are very similar in karyomorphology, indicating a certain karyological uniformity withinFlacourtiaceae. Lacistema (2n = ca. 62) appears more isolated. On the other hand, theTiliaceae Grewia (2n = 18) andLuhea (2n = 36) have much in common and differ remarkably from the Flacourtiaceous genera. The salicoid leaf-teeth ofProckia are also found inIdesia, but never inTiliaceae. Epidermis ultrastructure reveals certain relationships betweenProckia andFlacourtia in contrast to the strongly differingGrewia. Idesia has a rare und unique epidermis sculpture. — Basic chromosome numbers and chromosomal evolution within theFlacourtiaceae are discussed.
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5.
Due to the unique floral and pollen morphology of the genus Craigia its systematic position, whether in the family Sterculiaceae or in the family Tiliaceae, has often been debated. In order to add more evidence for solving this problem, a comparative study on pollen morphology of the genus and 15 species of 3 tiliaceous genera, viz.: Tilia Linn., Hainania Merr. and Excentrodendron Chang. et Miau. was carried out under the light and scanning electron microscope. The result shows that the polarity, the structure and position of the aperture of Craigia pollen differ from those in Tiliaceae but are similar to those in Sterculiaceae. From palynology, it is more appropriate to place the genus under discussion in Sterculiaceae than in Tiliaceae.  相似文献   

6.
7.
Five new Stenella species were found on native cerrado plants. Stenella erythroxyli-campestris, S. erythroxyli-suberosi and S. erythroxylicola were associated with plant species belonging in the family Erythroxylaceae; S. cyrtopodii was found infecting the rare Cyrtopodium eugenii (Orchidaceae), and S. ocoteae occurred on Ocotea sp. (Lauraceae). Finally Parastenella callisthenis-fasciculatae was collected on a Vochysiaceae (viz. Callisthene fasciculate) endemic to the cerrado.  相似文献   

8.
作者系统整理了中国五节根蚜亚科Fordinae标本,发现2新属:离倍蚜属DimelaphisZhang,gen.nov.和拟孕蚜属SicifordaZhng,gen.nov.;5新种:榆钱毛根蚜ChaetogeolcaulmidrupaZhang,sp.nov,钝镰离倍蚜D.obtusifalcataZhang,sp.nov,金黄五节根蚜FordaauralentaZhngetQiao,sp.nov,毛多五节很蚜F.multicomaZhng,sp.nov.及六节拟孕蚜S.sexiarticulataZhang,sp.nov.二新亚种:麦拟根蚜沾化亚种ParacletuscimicformiszhanhuanusZhng,ssp.nov。模式标本保存在中国科学院动物研究所。  相似文献   

9.
The paper describes structural features of megaspores from the Middle Gondwana (Middle Triassic) beds of Nidhpuri. These include two species of Srivastavaesporites Bharadwaj et Tiwari viz. S. triassicus sp. nov. and S. major sp. nov.; Grambastisporites nidhpurensis gen. et sp. nov.; Trikonia emarginata gen. et sp. nov.; one species of Mamillaespora Pant et Srivastava, M. sidhiensis sp. nov.; Nidhitriletes spinosa gen. et sp. nov.  相似文献   

10.
The Hordeum parodii group contains three species, viz. H. parodii Covas (6x), H. tetraploidum Covas (4x), and H. fuegianum Bothmer, Jacobsen, et Jørgensen, sp. nov. (4x). The former two species mainly occur in C and S Argentina, while H. fuegianum is native to Tierra del Fuego. All three species are probably of alloploid origin. Morphological, isoenzyme variation and cytogenetic data are presented.  相似文献   

11.
梧桐科一些属的分类位置探讨   总被引:4,自引:1,他引:4  
梧桐科(Sterculiaceae)是锦葵目中的一个多型科,科的特征比较比样化。自从E.P.Ventenat(1830)建立该科以来,对于该科范围和包含的属种数目,各国学者至今尚存在各种不同的看法。作者认为,火桐属(Erythropsis)应当从梧桐属(Firmiana)中分出成为单独的属;午时花属(Pentapetes)不应归入锦葵科(Malvaceae),应当置于梧桐科;田麻属(Corchor  相似文献   

12.
Plants harvested in the Canary Islands Lanzarote and Fuerteventura were analyzed for the yeasts inhabiting their surface. Half of the isolates (22 out of 44) were identified as Debaryomyces hansenii. Black ascomycetes, viz. Hortaea werneckii and two Hormonema species were represented by 7 strains. Basidiomycetous yeasts, viz. Cryptococcus sp. (8 strains), Rhodotorula sp. (5 strains), Cerinosterus cyanescens (1 strain) and Pseudozyma sp. (1 strain) constituted a minority of 33%. Thirty strains were screened for their ability to assimilate various plant constituents including lipids of the cuticle and the cell membrane, hemicelluloses, nitrogenous compounds (protein, nucleic acids, amino acids) and benzene compounds. All strains were able to assimilate or to hydrolyze lipids, lecithin included. Many strains of D. hansenii, H. dematioides, H. werneckii, C. cyanescens, Cr. laurentii, Pseudozyma sp. and Rh. glutinis were proteolytic. Hemicelluloses like xylan and pectin were assimilated by black ascomycetous yeasts, Cryptococcus sp., Pseudozyma sp. and Rh. glutinis. Ferulic and hydroxycinnamic acids, gallic and tannic acids were assimilated by some strains of H. dematioides, C. cyanescens, Pseudozyma sp. and Rhodotorula sp.  相似文献   

13.
The diversity of methanogenic archaea in enrichment cultures established from the sediments of Lonar Lake (India), a soda lake having pH ≈ 10, was investigated using 16S rDNA molecular phylogenetic approach. Methanogenic enrichment cultures were developed in a medium that simulated conditions of soda lake with three different substrates viz., H2:CO2, sodium acetate, and trimethylamine (TMA), at alkaline pH. Archaeal 16S rRNA clone libraries were generated from enrichment cultures and 13 RFLP groups were obtained. Representative sequence analysis of each RFLP group indicated that the majority of the 16S rRNA gene sequences were phylogenetically affiliated with uncultured Archaea. Some of the groups may belong to new archaeal genera or families. Three RFLP groups were related to Methanoculleus sp, while two related to Methanocalculus sp. 16S rRNA gene sequences found in Lonar Lake were different from sequences reported from other soda lakes and more similar to those of oil reservoirs, palm oil waste treatment digesters, and paddy fields. In culture-based studies, three isolates were obtained. Two of these were related to Methanoculleus sp. IIE1 and one to Methanocalculus sp. 01F97C. These results clearly show that the Lonar Lake ecosystem harbors unexplored methanogens.  相似文献   

14.
The paper describes the morphology and reproduction of a new species of Symphyonemopsis viz. S. pantii n. sp. isolated from enrichment cultures of a soil sample collected from the campus of Sangeet Samiti, Allahabad (India). Thalli grow as dark blue-green, small, wooly patches on soil surface but as cushion-like growths on agar plates. It has a prostrate and erect system. The latter bears secondary branches of almost equal breadth. It possesses both false and true branches. Usually true branches are reverse V-shaped. The alga shows formation of hormocysts and akinetes. In old cultures usually the main filament becomes multiseriate. The crescent-shaped stages of hormocysts are also present here. Cells of the present alga are constricted at the cross-walls On comparison it was found to come close to Symphyonemopsis katniensis Tiwari et Mitra but differs in certain fundamental characters. It is, therefore, described as a new species viz. S. pantii n. sp. (Cyanophyta, Stigonematales, Mastigocladaceae).  相似文献   

15.
We studied flight distance and directionality of bee pollinators on the tropical shrub weed Triumfetta semitriloba Jacq. (Tiliaceae), addressing (1) within- and between-plant movement pattern; (2) distances flown between plants; (3) flight directionality. Flowering plants were distributed in well-delimited clumps, in each of two pasture areas (A1 and A2) and one area of forest gap (A3), in Vi?osa, southeastern Brazil. Five solitary bee species, Augochlorella michaelis, Augochloropsis cupreola, Pseudocentron paulistana, Ceratinula sp., Melissodes sexcincta, and two social bee, Plebeia droryana, P. cf. nigriceps were observed. All species moved mainly to the nearest flower on the same individual plant and, in between-plant movements, to the first or second nearest neighbor. All species moved non-randomly, presenting a flight directionality in departures (maintenance of flight direction), but with a high frequency of turn angles. It is suggested that this foraging behavior pattern occurred because of the resource quantity and quality (pollen or nectar), and environmental characteristics such as flower density and resource distribution.  相似文献   

16.
Abstract It is assumed that the phytochemistry of browse species protects their biomass and nutrients against herbivory. In this study we were primarily interested in (i) seasonal and phenology‐related variations in leaf chemistry, and (ii) chemistry‐related variations in the feeding behaviour of domestic goats. Such knowledge would guide management‐orientated modelling of browse–browser interactions in seasonal, subtropical zones where goats are abundant. The browse species studied were typical of semiarid savannas in southern Africa: Grewia occidentalis L. (Tiliaceae), Scutia myrtina (Burm. f) Kurz (Rhamnaceae), Diospyros lycioides Desf. ssp. lycioides (Ebenaceae), Rhus longispina Eckl. and Zeyh. (Anacardiaceae), Ehretia rigida (Thunb.) Druce (Boraginaceae) and Acacia karroo Hayne (Mimosoideae). Nitrogen (N), phosphorus (P), condensed tannins (CT), protein‐precipitating tannins (PPT), total phenols (TP), cellulose and lignin concentrations were estimated for each species during the late dormant and early growing seasons. N, P, CT and TP were elevated during the growth season, while cellulose, lignin and PPT decreased. Unlike cytoplasm contents, which varied seasonally, cell wall and vacuole contents varied both seasonally and among species. Except that seasonal variation in N of deciduous species was greater than that of evergreen species, leaf phenology was not related to variations in forage quality. Short‐term intake rates were not related to primary metabolite concentrations, but were positively related to secondary metabolites. Elevated intake rates of putative defences were concluded to be side‐effects of attempts by goats to increase nutrient intake rate, indicating tolerance of chemical defences. Without support for the hypothesis that chemical defences are correlated to canopy retention, we propose an alternative hypothesis, that defences are distributed among woody plants in semiarid, subtropical savannas according to shoot morphology because it affects the vulnerability of plant parts to browsers.  相似文献   

17.
One new genus and five new species of dragonflies (Odonata) are described and figured from the Yixian Formation of northeastern China, viz. two gomphaeschnids Sinojoria magna nov. sp. and S. cancellosa nov. sp., plus three progobiaeshnids Mongoliaeshna hadrens nov. sp., M. exiguusens nov. sp., and Decoraeshna preciosus nov. gen., nov. sp. These new discoveries confirm the apparently sudden great diversification in China of the clade Aeshnoptera during the Middle-Upper Jurassic, together with the Upper Mesozoic to modern lineages of dragonflies. At the same time, some ‘ancient’ groups of Odonata became extinct.  相似文献   

18.
Siderophores of six fungi viz. Aspergillus sp. ABp4, Aureobacidium pullulans, Penicillium oxalicum, P. chrysosporium, Mycotypha africana and Syncephalastrum racemosum were examined for their (1) electrophoretic mobilities to determine the acidic, basic or neutral charge; (2) Fe (III) binding nature viz., mono-, di-, or trihydroxamate; (3) amino acid composition; and (4) NMR (nuclear magnetic resonance) spectroscopy to determine their structure. Electrophoretic mobilities of siderophores of 3 fungi (P. oxalicum, P. chrysosporium, and M, africana) exhibited net basic charge, siderophores of 2 fungi (Aspergillus sp. ABp4 and S. racemosum) were acidic and 1 fungus (A. pullullans) was neutral. Electrophoresis of ferrated siderophore at pH 2 and colour of the spots indicated that siderophores of Aspergillus sp. ABp4 and P. oxalicum and A. pullulans were trihydroxamates, whereas siderophore of P. chrysosporium was dihydroxamate. Amino acid composition of siderophores purified by XAD-2 column chromatography, revealed the presence of asparagine, histidine, and proline in Aspergillus sp. ABp4, serine and alanine in P. chrysosporium, and valine in M. africana. The structure of purified siderophores as revealed by NMR spectroscopy identified siderophore of AB - 2670 (A. pullulans) as asperchrome F1, and AB-513 (M. africana) as rhizoferrin. The peak obtained for siderophore AB-5 (Aspergillus sp. ABp4) did not show resemblance to any known siderophore, therefore may be an exception.  相似文献   

19.
Structures of cell wall anionic polymers of the strain Streptomyces sp. VKM Ac-2124, a causative agent of potato scab, which is phylogenetically the closest to plant pathogenic species S. setonii and S. caviscabies, were studied. The strain contains three anionic glycopolymers, viz., a teichuronic acid with a disaccharide repeating unit -->6)-alpha-d-Glcp-(1-->4)-beta-d-ManpNAc3NAcA-(1-->, a beta-glucosylated polymer of 3-deoxy-d-glycero-d-galacto-non-2-ulopyranosonic acid (Kdn), and a beta-glucosylated 1,5-poly(ribitol phosphate). The strain studied is the second representative of plant pathogenic streptomycetes inducing potato scab disease, the cell wall anionic polymers of which were shown to contain a Kdn-polymer. Presumably, the presence of Kdn-containing structures in the surface regions of pathogens is essential for their efficient attachment to host plant cells.  相似文献   

20.
The cell wall of Streptomyces sp. MB-8 contains a major teichoic acid, viz., 1,3-poly(glycerol phosphate) substituted with N-acetyl-alpha-D-glucosamine (the degree of substitution is 60%), a minor teichoic acid, viz., non-substituted poly(glycerol phosphate), and a family of Kdn (3-deoxy-D-glycero-D-galacto-non-2-ulopyranosonic acid)-containing oligomers of the following general structure: [carbohydrate structure: see text]. The composition of the oligomers was established using MALDI-TOF mass spectroscopy. The present study provides the second example of the identification of Kdn as a component of cell wall polymers of streptomycetes, which are the causative agents of potato scab.  相似文献   

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