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1.
One hundred isolates of 27 species belonging to 13 genera of dematiaceous hyphomycetes were screened for production of cytochalasins A and B. Most of these isolates (94) were obtained from Assiut University Culture Collection, Botany Department, Faculty of Science, Assiut University, Egypt; three isolates from CBS, The Netherlands; two isolates from DSM, Germany; and one isolate from IMI, UK. The results revealed that 10 isolates of six species representing five genera of fungi produced cytochalasins A and/or B. These species are Alternaria chlamydospora, Cochliobolus spicifer, Diplococcum spicatum, Phoma herbarum, Phoma multipara and Setosphaeria rostrata. This is the first report for the production of cytochalasins A and/or B by these species of dematiaceous hyphomycetes.  相似文献   

2.
Two standard strains and five local isolates of Saccharomyces cerevisiae all produced extracellular -1,6-glucanases in a growth-associated manner. Glucose at 2% (w/v) enhanced enzyme production up to 0.8 U ml-1. Optimum activity was at pH 5.0.The authors are with the Department of Microbiology. University of Dhaka, Dhaka 1000, Bangladesh  相似文献   

3.
Summary The genusGymnoascus Baranetzky is monographed and found to include five valid species including one previously recognized species,G. reessii, one new combination,G. johnstoni, two new species,G. longitrichus andG. corniculatus, and a species originally described as aGymnoascus but included inMyxotrichum since 1893,G. uncinatus. Twenty species previously described as belonging toGymnoascus are excluded from the genus or are considered as doubtful representatives.Supported in part by Botany Department Research Grant # 1344, University of California, Los Angeles, California.  相似文献   

4.
Summary Field studies indicated that subterranean aecia ofPuccinia menthae Pers. are of little significance in the initiation of spearmint rust infection in undisturbed fields. Also, wild or escaped mints do not appear to be of significance. The primary source of inoculum comes either from fields that are not fall plowed or from infected rhizomes or transplants during spring planting. Temperatures during May appear to be critical in the development of rust epiphytotics. The predominant race of the pathogen occurring in Indiana corresponds to Race 1.Respectively, former graduate research assistant, Department of Botany and Plant Pathology, Purdue University, presently Assistant Plant Pathologist, University of Arizona, Mesa Branch Experiment Station, Mesa, Arizona; and Associate Plant Pathologist, Department of Botany and Plant Pathology, Purdue University, Lafayette, Indiana. Journal paper 2691. The authors thank Dr.M. J. Murray, A. M. Todd Company, Kalamazoo, Michigan, for species ofMentha used as race differentials. This research was supported, in part, by funds provided through the Mint Industries Research grant.  相似文献   

5.
Utricularia inflexa Forsk. growing in a shallow lake near Dar es Salaam, Tanzania was found to be abundantly associated with blue-green algae and other microorganisms, though blue-green algae were not found in the lake water. The epiphytes occurred both on the outer surfaces of the macrophyte and inside its traps. Seven genera of the Cyanophyta were observed, amongst which Anabaena was the most abundantly and consistently associated.Both epiphytes on the outer surfaces of the macrophyte and those inside mature traps fixed nitrogen in situ. Mature parts of the macrophyte fixed nitrogen at higher rates than immature parts, indicating the former was associated with a greater abundance of nitrogen fixers. The Utricularia-Cyanophyta association showed a nitrogen fixation (acetylene reduction) rate of 2012 nmol C2H4 g–1 dry weight h–1 or, in terms of lake area, of 4 500 nmol C2H4 m–2 h–1. The relative contributions of blue-green algae and bacteria were not determined.It is proposed that the association may involve a degree of physiological interdependence and that the association has potential as a biofertilizer for rice.Based on an M.Sc. thesis by G. M. Wagner submitted to the Department of Botany, University of Dar es Salaam, 1983.Based on an M.Sc. thesis by G. M. Wagner submitted to the Department of Botany, University of Dar es Salaam, 1983.  相似文献   

6.
de Wet , J. M. J. (Div. Botany, Pretoria, So. Africa.) Chromosome numbers and some morphological attributes of various South African Grasses. Amer. Jour. Bot. 47(1): 44—49. Illus. 1960.– Chromosome numbers are reported for 68 species and varieties of grasses belonging to 40 genera. These include first reports for the genera Megastachya, Lintonia, Plagiochloa, Ctenium, Oropetium and Beckeropsis. Cytological data were correlated with observations from leaf and embryo anatomy. A common ancestor is postulated for the tribes Oryzeae, Ehrharteae and Centotheceae. The genera Lasiochloa, Plagiochloa and Urochlaena appear to belong neither with the tribe Festuceae nor with the Eragrosteae but probably are closer related to the Danthonieae. Lintonia. Entoplocamia, Tetrachne and Fingerhuthia are characterized by the chloridoid-eragrostoid type of cytology and leaf anatomy but the bambusoid type of embryo anatomy. For these reasons they appear to represent relics of the original Eragostoid and Chloridoid stock. The South African representatives of the genus Crinipes differ from the tropical species in respect to leaf anatomy. The tropical species are typically of the arundinoid type, whereas the South African species appear to be related to the Danthonieae.  相似文献   

7.
Keratinophilic fungi were isolated from corridor dust of 11 hospitals and soils of 21 public places using a hair baiting technique. A total of 41 species belonging to 24 genera were recovered. Among the dermatophytes and related species, Microsporum gypseum was predominant, followed by Chrysosporium keratinophilum, Trichophyton mentagrophytes, M. nanum and Ch. tropicum. Other species were represented by 32 species belonging to 21 genera. Most of the species isolated are known to be agents of human and animal infection or have been isolated from human and animal lesions. The fungi observed here are discussed in relation to their global distribution.  相似文献   

8.
J. R. Caradus 《Plant and Soil》1990,123(2):165-167
Genotypes of two morphologically different populations of white clover (Trifolium repens L.) were reciprocally and self-grafted. Ungrafted stolon tips were also grown as controls. Grafting per se had no significant effect on shoot size, root size, leaflet width or shoot and root % P. The scion genotype had a significant effect on shoot and root size, and leaflet width. Neither scion nor rootstock genotype had a significant effect on either shoot or root % P. However, there was a significant scion × rootstock × P level interaction for shoot % P. This along with other evidence suggests that conflicting results regarding effects of scion and rootstock on % P content of plants within species is probaby due to the interaction of scion and rootstock with environment.This work was undertaken at the Department of Agricultural Botany, University of Reading, Reading, England.This work was undertaken at the Department of Agricultural Botany, University of Reading, Reading, England.  相似文献   

9.
A new species of the endogonaceous fungus Gigaspora, isolated from the Indian semi-arid region, is described. The fungus, named G. tuberculata, produces rusty-brown azygospores with septate subtending hypha. The azygospores bear warts all over the outer wall. The shape, size and general appearance of these spores resemble those of Scutellospora persica.Neeraj and A.K. Varma are with the Microbiology Unit, School of Life Sciences, Jawaharlal Nehru University, New Delhi 110 067, India; K.G. Mukerji is with the Applied Mycology Laboratory, Botany Department, University of Delhi, Delhi 110 006, India. B.C. Sharma is with the Department of Textile Engineering, Indian Institute of Technology, New Delhi 110 016, India.  相似文献   

10.
By means of field investigation, specimen identification and related literatures, five species belonging to five genera in three families of angiosperms were identified as new records in Southwest of Guangxi, viz. Whytockia hekouensis Y. Z. Wang, Aeschynanthus chiritoides C. B. Clarke, Petrocodon insliifolius W. H. Chen et Y. M. Shui, Alseodaphne marlipoensis ( H. W. Li) H. W. Li and Cheirostylis malipoensis X. H. Jin et S. C. Chen. Voucher specimens are deposited in Herbarium of Guangxi Institute of Botany ( IBK) .  相似文献   

11.
农素芸  陆昭岑  陈海玲  许为斌 《广西植物》2023,43(12):2196-2202
该文报道了广西维管植物5个新记录属和种,即双角草属(Diodia L.)、伏金腰箭属(Calyptocarpus Less.)、兔儿伞属(Syneilesis Maxim.)、凤头黍属(Acroceras Stapf)和落芒草属(Piptatherum P. Beauv.),以及隶属于该5属的双角草(Diodia virginiana L.)、金腰箭舅(Calyptocarpus vialis Less.)、兔儿伞[Syneilesis aconitifolia(Bunge) Maxim.]、山鸡谷草[Acroceras tonkinense(Balansa) C. E. Hubbard ex Bor]和钝颖落芒草(Piptatherum kuoi S. M. Phillips&Z. L. Wu)。其中双角草和金腰箭舅为归化种,文中提供了2个新归化种的形态描述和照片,并对其入侵性给予了评估;兔儿伞、山鸡谷草和钝颖落芒草为本土植物,提供了其特征集要描述和照片,并对其生物地理学意义进行了讨论。  相似文献   

12.
A total of 297 fungal isolates belonging to 20 genera and 33 species were isolated and identified from eggs and females of Meloidogyne spp. in Bangladesh. The predominant genera were Fusarium, Aspergillus and Penicillium; and the significant ones were Purpureocillium, Trichoderma and Pochonia. The 24 well tissue culture plate screening technique was applied for pathogenicity tests against Meloidogyne incognita in vitro. The average percentages of egg parasitism, egg hatch inhibition and juvenile mortality varied significantly and were ranged from 8.2 to 64.9% (p = 0.05), 24.8 to 72.4% (p = 0.05), and 2.3 to 33.1% (p = 0.05), respectively. Two isolates of Purpureocillium lilacinum (PLSAU 1 and PLSAU 2) and one isolate of Pochonia chlamydosporia (PCSAU 1) reduced more than 60% average root galls of tomato, eggplant and cucumber in greenhouse experiments. This is the first investigation of fungi associated with nematodes in the country and their biological control potential against M. incognita.  相似文献   

13.
采用土壤平板法和稀释平板法,自湖北神农架自然保护区的14份土壤样品中分离得到40个暗色丝孢菌分离物,鉴定为16属23种。其中,湖北弯孢Curvularia hubeiensis为一新种,嗜热革节孢Scytalidium thermophilum和禾色串孢Torula graminis为中国新记录种。对新种及中国新记录种作了详细的描述。其余20种为国内已报道种。所有研究菌株的干制培养物标本与活菌种均存放在山东农业大学植物病理学标本室(HSAUP)。  相似文献   

14.
The conditions in densely populated Bangladesh favor picornavirus transmission, resulting in a high rate of infection in the human population. Data suggest that nonhuman primates (NHP) may play a role in the maintenance and transmission of diverse picornaviruses in Bangladesh. At the Dhaka Zoo, multiple NHP species are caged in close proximity. Their proximity to other species and to humans, both zoo workers and visitors, provides the potential for cross-species transmission. To investigate possible interspecies and intraspecies transmission of picornaviruses among NHP, we collected fecal specimens from nine NHP taxa at the Dhaka Zoo at three time points, August 2007, January 2008, and June 2008. Specimens were screened using real-time PCR for the genera Enterovirus, Parechovirus, and Sapelovirus, and positive samples were typed by VP1 sequencing. Fifty-two picornaviruses comprising 10 distinct serotypes were detected in 83 fecal samples. Four of these serotypes, simian virus 19 (SV19), baboon enterovirus (BaEV), enterovirus 112 (EV112), and EV115, have been solely associated with infection in NHP. EV112, EV115, and SV19 accounted for 88% of all picornaviruses detected. Over 80% of samples from cages housing rhesus macaques, olive baboons, or hamadryas baboons were positive for a picornavirus, while no picornaviruses were detected in samples from capped langurs or vervet monkeys. In contrast to our findings among synanthropic NHP in Bangladesh where 100% of the picornaviruses detected were of human serotypes, in the zoo population, only 15% of picornaviruses detected in NHP were of human origin. Specific serotypes tended to persist over time, suggesting either persistent infection of individuals or cycles of reinfection.  相似文献   

15.
Anbu P  Hilda A  Gopinath SC 《Mycopathologia》2004,158(3):303-309
Soils of 10 poultry farms from Namakkal and 12 feather dumping sites from Chennai were studied for the presence of keratinophilic fungi. A total of 34 species belonging to 19 genera and one non-sporulating fungus were recovered. Sixteen species of fungi and one non-sporulating fungi were common to both sites, eight species were specific to Namakkal and nine species were specific to Chennai. Dermatophytes and closely related fungi were represented by six species belonging to five genera. Fungal species commonly found in the soil samples included Chrysosporium keratinophilum (73%), Trichophyton mentagrophytes (68.2%), Microsporum gypseum (64%), Myceliopthora vellerea (32%), Chrysosporium state of Arthroderma tuberculatum (27.3%) and Geomyces pannorum (23%). Non-dermatophyte fungi were represented by 28 species belonging to 14 genera and one non-sporulating fungus.  相似文献   

16.
Summary Organic amendments reduced the percentage infection of root rot and wilt of pea due to Fusarium solani f. sp. pisi. A fair amount of control of the disease can be obtained by the millet straw with additional ammonium nitrate.All the fungicides (Bavistin, Miltox, Cosan and Blitane) except Calixin showed decrease in the percentage infection when applied to the soil (200 ppm w/w). With Bavistin treated soil the infection was only 8% followed by Blitane, Cosan and Miltox.Department of Botany, B.N. Chakravarty University, Kurukshetra (Haryana), India.Department of Botany, University College, Kurukshetra (Haryana) India.  相似文献   

17.
A list of the Annonaceae taxa native to the Indo‐Burmese Region is presented. Species are listed with synonyms and types, and the regional distribution is given by country (India, Sri Lanka, Pakistan, Nepal, Bhutan, Bangladesh and Burma). In total, 195 species from 28 genera are listed. Two new combinations, Monoon nitidum (A. DC.) I. M. Turner and Polyalthia malabarica (Bedd.) I. M. Turner, are included. Polyalthia corticosa (Pierre) Finet & Gagnep. is considered the correct name for P. obliqua in India and Bangladesh. Artabotrys cubittii Chatterjee is reduced to a synonym of A. burmanicus A. DC. Two new records for Burma, Polyalthia bullata King and Uvaria hahnii (Finet & Gagnep.) J. Sinclair, are presented.  相似文献   

18.
Phytoplankton ecology of the Lake of Menteith,Scotland   总被引:1,自引:1,他引:0  
The results discussed in this paper represent the first seasonal ecological study carried out on the phytoplankton of the Lake of Menteith. All measured nutrients reached maximum levels during the winter, with silicate showing particularly high concentrations (up to 85 µg at Si l–1). During the summer period phosphate, nitrate and silicate showed almost complete exhaustion in surface waters. The lake water was consistently alkaline, never falling below pH 7, while the alkalinity ranged from 20 to 24 mg CaCO3 l–1. Generally, the nutrient status of the main inflow had a rapid effect on the water quality of the lake.The region of the lake under investigation showed no thermal stratification at any period of the year, although continuous thermal gradients were recorded in the winter. The continual circulation of the water mass probably prevented oxygen saturation from falling below 77% even following a large phytoplankton bloom and subsequent decomposition.From an examination of net phytoplankton samples the Lake of Menteith could be described as blue-green or blue-green/diatom in nature. From the quantitative study, large pulses of Melosira, Asterionella and Fragilaria were recorded in the spring. The disappearance of the species appears to be related to silicate limitation. The summer growth of Asterionella may have been promoted by a nitrogen source other than nitrate and nitrite, both of which were reduced to critical levels. This alternative source of combined nitrogen may have been contributed by nitrogen-fixing algae in the lake. Three species of Anabaena were recorded, all of which produced large populations during the year.Department of Botany, The University of GlasgowPresent Address: Department of Biology, College of Science, University of Sulaimaniyah, Sulaimaniyah, Iraq  相似文献   

19.
Nagy, Z. T., Glaw, F. & Vences, M. (2010) Systematics of the snake genera Stenophis and Lycodryas from Madagascar and the Comoros. —Zoologica Scripta, 39, 426–435. Arboreal snakes belonging to the pseudoxyrhophiine genus Stenophis inhabit Madagascar but despite their spectacular appearance, surprisingly little is known about their natural history and systematics. Nonetheless, a close phylogenetic affinity of the genera Stenophis and Lycodryas (the latter genus currently includes a single species from the Comoros) has been hypothesized. Based on recent molecular genetic data, however, the monophyly of Stenophis was challenged. This study aimed at a systematic analysis and taxonomic revision of the genera Stenophis and Lycodryas. On the basis of new molecular genetic and morphological data and analyses, we propose to accommodate these snakes in three monophyletic genera: Lycodryas, Phisalixella and Parastenophis, and to consider Stenophis as a junior synonym of Lycodryas. In the new generic arrangement, the genera can also be well distinguished by morphological characters. On the specific level, Phisalixella tulearensis is resurrected and indications of further, undescribed taxa are revealed.  相似文献   

20.
Morphological types of arbuscular mycorrhizas (AM) in pioneer woody plants were examined in an oil palm farm 1 year after reclamation. In total, 18 plant species belonging to 15 genera in 9 families were examined, and the Arum type was found in 12 species belonging to 9 genera in 5 families. In contrast, the Paris type was found in 5 species belonging to 5 genera in 4 families. The number of plant species with Arum-type AM was always higher than that with Paris-type AM in all four sampling plots. All the examined species in Euphorbiaceae, most of which are fast-growing pioneer trees and were dominant in forming the canopy in secondary forests, were found to have Arum-type AM. These results suggest that Arum-type colonization is beneficial for fast-growing woody plant species.  相似文献   

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