Ecology of tropical marine fungi

Lignicolous material was collected from 5 marine locations in Brunei: a rocky headland, a sandy beach, a man-made brackish lake, a healthy mangrove and an oil polluted mangrove. Higher marine fungi present were identified and their percentage occurrence noted. The common marine fungi varied from habitat to habitat. Antennospora quadricornuta was most common at the rocky headland, Corollospora pulchella at the sandy beach and Halosarpheia marina at the brackish lake. In the mangroves the most common species were Halocyphina villosa (healthy) and Cirrenalia pygmea and Lulworthia grandispora (oil polluted). Differences in species composition from one habitat to the next were observed, although some fungi occurred throughout. There were significantly less diversity and numbers of fungi in the oil polluted mangrove when compared to the healthy mangrove. Observations concerning the ecology of tropical marine fungi are made.     

Marine mycoflora of south India with special emphasis on lignicolous marine fungi

A study dealing with the marine fungi associated with decaying wood samples in the brackish water mangrove ecosystem and shoreline ecosystem was carried out in south India. A total of 19 marine fungi were isolated from the brackish water mangrove ecosystem. They included 13 Ascomycetes, one Basidiomycete and five Mitosporic fungi. In terms of percent frequency of occurrence, the most frequent species obtained from the brackishwater were the Lignincola longirostris (16.60%) and Savoryella lignicola (12.09%). Nine species were found frequently. Five species were occasionally encoun-tered. Aigialus mangrovei, Aniptodera mangrovei and Halosarpheia marina were the rare species recorded. The average number of isolates per wood sample was 1.53. A total of 27 marine fungi including 15 ascomycetes, one basidiomycete and ten mitosporic fungi were recorded from the shoreline ecosystem. In terms of percent frequency of occurrence, the most frequent species obtained from Kanyakumari were the Arenariomyces trifurcates (13.66%), Corollospora maritima (12.44%), and Cirrenalia pygmea (10.98%). Seven species were found frequently. Fourteen species were occasionally encountered. Three species were found to be rare in occurrence. The average number of isolates per wood sample was 1.21.     

Diversity and abundance of nematode-trapping fungi from decaying litter in terrestrial, freshwater and mangrove habitats

Nematode-trapping fungi are ubiquitous in terrestrial habitats in dung, soils, litter and woody debris and they also occur in freshwater, but only one species has been found in marine habitats. The purpose of this study was therefore to investigate whether nematode-trapping fungi occurred in mangrove habitats. To achieve this we assessed the diversity of nematode-trapping fungi on decaying litter from mangroves, freshwater and terrestrial habitats (22 sites) in Hong Kong. Composite samples (n = 1,320) of decaying litter (wood and leaves) were examined and a total of 31 species of nematode-trapping fungi belonging to four genera, Arthrobotrys, Monacrosporium, and Dactylella were recorded. Twenty-nine species reported in this study are new records for Hong Kong and 16 species are new records from mangrove habitats worldwide. Nematode trapping fungi are therefore present in marine environments. Commonly encountered taxa were Arthrobotrys oligospora and Monacrosporium thaumasium which are abundant in all habitats. A. oligospora, M. thaumasium and Arthrobotrys musiformis were frequent (F > 10%). Twenty-six species were rare (0.16–9.32%). Species richness and diversity was higher in terrestrial than in freshwater and mangrove habitats (ANOVA, P < 0.001). A higher mean diversity was observed on decaying leaves as compared to decaying wood in all habitats (P < 0.001). Based on Shannon diversity index, it was also observed that taxa characterized by adhesive nets were more frequent in all habitats. This can be explained by the fact that these taxa may have a better competitive saprotrophic ability which would allow them to compete favourably in nutrient limited environments. Abiotic factors that could be linked to differences in species diversity between decaying wood and leaves are also discussed.     

Fungi from decaying intertidal fronds of Nypa fruticans, including three new genera and four new species

HYDE, K. D., 1992. Fungi from decaying fronds of Nypa fruticans, including three new genera and four new species. Decaying fronds and exposed stems of the mangrove palm Nypa fruticans were collected from beaches and intertidal regions of mangroves in Brunei and examined for the presence of higher marine fungi. Forty-three species were identified, four of which are new to science. The fungi included 32 Ascomycotina, one Basidiomycotina and ten Deuteromycotina. Three new genera and four new species are described and illustrated.     

湛江红树林滩涂可培养真菌种群多样性分析

【目的】明确湛江地区红树林滩涂海洋真菌的种类及其分布,为海洋真菌的开发利用研究奠定基础。【方法】运用稀释平板法从湛江市高桥及特呈岛红树林滩涂不同的潮位带(低、中、高)和不同树种(白骨壤、桐花树、木榄、红海榄)采集淤泥样品550份,采用真菌形态学和ITS序列分析技术进行多样性研究【。结果】分离获得海洋真菌274株,共鉴定出19属39种真菌,以曲霉属Aspergillus、青霉属Penicillium和木霉属Trichoderma真菌分离频率高,为湛江红树林滩涂优势真菌种类,尤其在中潮位带真菌种类最多。此外,分离获得真菌Talaromyces helicus,为中国新记录种。【结论】湛江红树林滩涂海洋真菌的种类十分丰富,具有潜在的开发和利用前景。     

红树林湿地海洋真菌多样性研究进展

红树林湿地是位于热带、亚热带海湾、河口的潮间带滩涂,是一个复杂、特殊的生态体系。红树林湿地具有丰富的真菌资源,是海洋真菌的第二大类群。文中对红树林湿地海洋真菌界定、资源数量、地理分布及其影响因素和基质多样性进行了概述。     

不同生境具有抗肿瘤活性的海洋真菌筛选

目的:为了测定海口沿海海域不同生境的海洋真菌抗肿瘤状况。方法:我们从海口西海岸沿线、南渡江入海口处以及演丰红树林三个不同生境分离到162株海洋真菌,通过MTT比色法测定海洋真菌代谢产物对黑色素瘤B16的抑制活性。结果:其中75.93%的海洋真菌代谢产物对B16细胞增殖有不同的抑制作用,来自西海岸沿线生境的真菌有77.36%具有抑制B16生长作用,来自入海口生境的真菌为77.27%,来自红树林的真菌为70.58%,并且不同生境的真菌代谢物的细胞毒性强弱也有明显的区别。结论:不同生境的真菌具有不同的抗肿瘤作用,筛选具有某种活性海洋真菌菌株时,可以选择容易产某种活性成分的目的生境。     

广西北部湾红树植物内生真菌多样性

【目的】研究广西北部湾地区红树植物内生真菌多样性,建立北部湾红树植物内生真菌种质资源库,为利用内生真菌生物技术促进农业可持续发展提供理论依据。【方法】从广西北部湾地区采集红树植物组织样本,采用表面消毒法分离真菌,通过测定分离菌株对宿主植物是否具有致病性来筛选内生真菌,结合形态学特征和分子生物学分析对内生真菌进行分类与鉴定。【结果】从60个红树植物样本中分离得到1 764个菌株,经过致病性测定筛选获得41株内生真菌,分离率为2.3%。其中从宿主植物红海榄分离得到15株内生真菌,占总菌株数的36.6%,比例最高。通过分析,发现这些内生真菌在ITS-NJ、NS-NJ两个系统发育树上各聚为7个大分支,分属8个科(目)。其中球腔菌属Mycosphaerella、德福里斯孢属Devriesia、假尾孢属Pseudocercospora、枝孢霉属Cladosporium、Pleosporales等属(科)真菌是广西红树林的优势菌。【结论】广西北部湾地区红树植物内生真菌菌种资源丰富。     

广西红树林的病原真菌及其生态学特点

报道了广西沿海的山口、钦州、北仑河口 3个主要红树林分布区的病原真菌及其生态学特点 :共鉴定红树林病原真菌 1 4属 2 6个种 (菌株 ) ,其中主要是炭疽菌、拟盘多毛孢菌、交链孢菌和叶点霉菌。 3个分布区红树林病原真菌的物种丰富度指数 DMA在 2 .82 65～ 4 .70 0 4之间 ,多样性指数 H'为 0 .971 8～ 1 .2 768,均匀度指数JSW为 0 .90 0 5～ 0 .91 58;其中山口病原真菌的种数 ( 1 2 )最少 ,物种丰富度指数 ( 2 .82 65)和物种多样性指数( 0 .971 8)最小。红树林病原真菌分布的主要特点是 :高潮地带的较低潮地带的为多 ,尤以河口最多。侵染寄主的部位主要集中在树冠上部 ,叶斑病最常见 ,枝梢病害次之 ,根茎部的病害很少。桐花和海漆的病害种类最多 ,红海榄和老鼠筋最少。     

红树林内生真菌研究进展

红树林作为一种特殊的植物群落具有丰富的内生真菌资源,目前已分离鉴定的红树林真菌超过200种,成为海洋真菌的第二大类群,已报道的红树林内生真菌主要类群是链格孢霉(Alternaria)、曲霉(Aspergillus)、芽枝霉(Cladosporium)、炭疽菌(Colletotrichum)、镰孢霉(Fusarium)、拟青霉(Paecilomyces)、拟盘多毛孢(Pestalotiopsis)、青霉(Penicillium)、茎点霉(Phoma)、拟茎点霉(Phomopsis)、叶点霉(Phyllosticta)和木霉(Trichoderma)等.大部分红树林内生真菌具有较宽的宿主范围,极少数只有单一的宿主,不同红树林植物的内生真菌区系及优势种群有很大差异.红树林内生真菌的定殖因宿主植物不同部位、植株的年龄及季节和环境的变化明显不同.红树林内生真菌能产生多种代谢产物,具有抗菌、抗肿瘤等药用价值.红树林植物内生真菌的研究和开发具有重要意义.本文综述了红树林内生真菌的生物多样性及其分布、生物学功能和次生代谢产物等方面的研究进展.     

红树林生态系统中不同生境不同深度土壤的可培养真菌的多样性

【目的】了解八门湾红树林生态系统中不同生境(潮间带、海洋到红树区的过渡带、海桑红树区)和不同深度土壤的可培养真菌的多样性。【方法】采用稀释涂布平板法分离土壤中的真菌,利用形态学观察和ITS rDNA序列分析技术研究可培养真菌的表观和遗传多样性。【结果】从八门湾红树林生态系统的3个不同生境中分离到257株真菌,分别属于21属28种,其中青霉属(Penicillium)、曲霉属(Aspergillus)和木霉属(Trichoderma)为优势类群。来自不同生境或者同一生境不同采样深度的土壤真菌种类组成不同,并且有些真菌类群只出现在特定的样品中。从空间角度看,红树区土壤样品的真菌多样性高于其他两个生境的土壤样品;从垂直角度看,潮间带和过渡带的表层土壤样品的真菌多样性高于深层土壤样品,而红树区的深层土壤样品真菌多样性高于表层土壤样品。【结论】八门湾红树林生态系统中的可培养真菌资源丰富,种类多样性较高,但不同生境或不同深度的可培养真菌分布存在较大的差异。这些结果揭示了红树林土壤中可培养真菌的生态分布特点,也为红树林真菌资源的开发利用提供了基础的背景资料。     

Vertical distribution of marine fungi onRhizophora apiculata at Morib mangrove, Selangor, Malaysia

Studies on the vertical distribution of marine fungi in aRhizophora apiculata mangrove stand in Morib, Selangor were carried out in June 1993 and June to November 1997. Prop roots, subterranean roots and overhanging branches ofR. apiculata were collected from three intertidal levels namely upper (high water mark), middle and lower. Fifty-three species were recorded including 39 ascomycetes, 13 deuteromycetes and one basidiomycete. The most common fungi wereHalocyphina villosa (frequency occurrence 21%),Kallichroma tethys (20%),Lulworthia grandispora (18%),Leptosphaeria australiensis (16%),Julella avicenniae (15%) andMassarina ramunculicola (13%). The fungi were found to be vertically zoned, some were limited to the upper level such asPyrenographa xylographoides, Julella avicenniae andAigialus grandis or lower level such asTrichocladium achrasporum andT. alopallonellum, while only five species showed a broader distribution, being present at all levels:Leptosphaeria australiensis, Halocyphina villosa, Cryptovalsa sp.,Lulworthia grandispora andLulworthia sp. The greatest diversity of marine fungi were collected from the middle level with a Shannon Diversity Index of 5.9 while the Jaccard Similarity Index of 2.25 indicated that the upper and middle levels were the most similar in terms of species composition. Fungi with certain characteristics were also limited to particular levels, for example, carbonaceous and superficial ascomata were confined above mean tide while membranous walls and immersed ascomata were common below mean tide level.     

Marine mycoflora of south India with special emphasis on lignicolous marine fungi

A study dealing with the marine fungi associated with decaying wood samples in the brackish water mangrove ecosystem and shoreline ecosystem was carried out in south India. A total of 19 marine fungi were isolated from the brackish water mangrove ecosystem. They included 13 Ascomycetes, one Basidiomycete and five Mitosporic fungi. In terms of percent frequency of occurrence, the most frequent species obtained from the brackishwater were the Lignincola longirostris (16.60%) and Savoryella lignicola (12.09%). Nine species were found frequently. Five species were occasionally encountered. Aigialus mangrovei, Aniptodera mangrovei and Halosarpheia marina were the rare species recorded. The average number of isolates per wood sample was 1.53. A total of 27 marine fungi including 15 ascomycetes, one basidiomycete and ten mitosporic fungi were recorded from the shoreline ecosystem. In terms of percent frequency of occurrence, the most frequent species obtained from Kanyakumari were the Arenariomyces trifurcates (13.66%), Corollospora maritima (12.44%), and Cirrenalia pygmea (10.98%). Seven species were found frequently. Fourteen species were occasionally encountered. Three species were found to be rare in occurrence. The average number of isolates per wood sample was 1.21.     

Frequency of occurrence of fungi on wood in Malaysian mangroves

Over one hundred fungi have been reported on mangrove wood (Hyde and Jones, 1988; Jones and Kuthubutheen, 1989; Hyde and Jones, unpublished) from tropical and subtropical locations. A variety of factors affect the frequency of occurrence of these fungi, e.g . salinity, length of exposure of substrate, wood species and location within the mangrove. Two aspects are addressed in this paper: a) Comparison of the fungi present at three mangroves in Malaysia (Morib, Kuala Selangor, Port Dickson); and b) The fungi colonising specific mangrove wood, e.g. Avecennia marina, Bruguiera gymnorrhiza. Species diversity was greatest at Port Dickson with 63 fungi recorded while species composition varied from site to site. Common fungi at Morib and Kuala Selangor were Halocyphina villosa and Leptosphaeria australiensis along with Kallichroma tethys and Lulworthia grandispora at the latter site. None of these were common at Port Dickson, the dominant species at this site were Hypoxylon oceanicum and Massarina ramunculicola. A comparison of the fungi occurring on Avicennia marina and Bruguiera gymnorrhiza indicated that Halocyphina villosa was common on both timbers. Species diversity and abundance were greatest on Avicennia with the following fungi listed as common: Eutypa sp., Kallichroma tethys, Marinosphaera mangrovei, Phoma sp. and Julelia avicenniae.     

Biodiversity and distribution of fungi associated with decomposing Nypa fruticans

Fungi associated with the decomposition of Nypa fruticans in Malaysia are under investigation. Forty-one fungi have been identified including 35 ascomycetes, four mitosporic fungi and two basidiomycetes. The distribution of intertidal fungi on palm structures including leaves, leaf veins, rachides, petiole bases, and inflorescences, and fungi on terrestrial parts have also been examined. No fungi were found on the leaf material, although several fungi were found on the leaf midribs, and possible reasons for this are given. Very few taxa developed on the inflorescences, but those that were present were abundant. The greatest density of fruiting structures occurred on the rachides, and the greatest diversity of fungal species occurred on the petiole bases. The terrestrial fungi differed from the intertidal fungi, although Linocarpon nipae occurred in both habitats. Reasons for the differences in fungal numbers and diversity on the various palm parts are discussed. The diversity of fungi at Morib mangrove was low when compared to previous studies on fungi on Nypa palm at Kampong Api Api in Brunei and in this study at Kuala Selangor mangrove in Malaysia.     

海南文昌清澜港红树林真菌抗B16肿瘤细胞活性菌株的筛选

从海南文昌清澜港红树林采集78份植物组织和土壤样品。对样品进行真菌分离, 共分离得到真菌608株, 采用目测法对其体外抗肿瘤细胞活性进行检测, 发现81株红树林真菌对小鼠黑色素瘤B16细胞有不同程度的抑制作用, 占总分离菌株的13.32%。结果表明, 从红树植物杯萼海桑中分离得到真菌菌株的数量最多, 而从红树植物银叶树分离得到的抗肿瘤细胞活性菌株数量最多。     

海南文昌清澜港红树林真菌抗B16肿瘤细胞活性菌株的筛选

从海南文昌清澜港红树林采集78份植物组织和土壤样品。对样品进行真菌分离, 共分离得到真菌608株, 采用目测法对其体外抗肿瘤细胞活性进行检测, 发现81株红树林真菌对小鼠黑色素瘤B16细胞有不同程度的抑制作用, 占总分离菌株的13.32%。结果表明, 从红树植物杯萼海桑中分离得到真菌菌株的数量最多, 而从红树植物银叶树分离得到的抗肿瘤细胞活性菌株数量最多。     

Arenicolous mycelial fungi from the littoral of the Vostok Bay (Peter the Great Bay,the Sea of Japan)

The taxonomic composition of marine mycelial fungi was determined in the interstitial habitats of the Vostok Bay littoral (Peter the Great Bay, the Sea of Japan). A total of 39 species of ascomycetes and anamorphic fungi were detected and identified. The predominant species of the intertidal zone were Corollospora maritima, C. lacera, Carbosphaerella leptosphaerioides, Arenariomyces trifurcatus (Ascomycota), Alternaria alternata, Scolecobasidium arenarium, and Zalerion maritimum (anamorphic fungi). The complete list of species of obligately marine ascomycetes and anamorphic fungi from the interstitial habitats of the Vostok Bay littoral is presented for the first time     

漳江口红树林沉积物真菌多样性分析及抗茶叶致病真菌生物活性筛选

以福建漳江口红树林国家级自然保护区红树林沉积物分离的真菌为对象,研究红树林沉积物真菌的多样性和筛选抗茶叶病原真菌活性的菌株。将分离纯化的135株真菌通过形态学和Ribosomal DNA-Internal Transcribed Spacer(rDNAITS)序列测定进行鉴定及多样性分析,归为40个种类型,分别属于17个属,其中青霉属(25%)为优势菌,木霉属(15%)、曲霉属(10%)和镰刀属(10%)次之,表明红树林沉积物真菌具有丰富的多样性;利用平板对峙法对真菌的发酵粗提物抗茶叶病原真菌生物活性研究,结果发现,共有17株(占42.5%)真菌具有抗茶叶病原真菌活性,其中15株能够抑制茶叶轮斑病(Pestalotiopsis theae)LH13,12株能够抑制茶叶炭疽病(Colletotrichum gloeosporioides)LH30,8株能够抑制茶叶溃疡病(Neofusicoccumsp.)LH107,有两株对这三种茶叶致病菌均有较强活性。这些活性菌株分布在6个属中,分别是青霉属(7株)、木霉属(3株)、镰孢属(2株)、枝孢属(2株)、白地霉属(2株)和球腔菌属(1株)。由此可见,红树林沉积物真菌抗菌活性菌株的种属分布具有多样性。     

Diversity of endophytic fungi in the roots of mangrove species on the west coast of India

Because mangrove plant species are a valuable source of useful metabolites, their endophytes have gained more importance. Randomly sampled surface-sterilized whole root segments of four mangrove plant species, Acanthus ilicifolius, Avicennia officinalis, Rhizophora mucronata, and Sonneratia caseolaris from the mangroves of Udyavara (Karnataka) on the west coast of India, were characterized for fungal communities by direct plating, damp chamber, and bubbling chamber incubation methods. The richness of endophytic fungal species from whole root segments after direct plating and damp chamber incubation was greatest for R. mucronata than for other plants (18 vs. 8-13). Incubation of whole root segments in bubbling chambers yielded conidia of two freshwater hyphomycetes: Mycocentrospora acerina (in Avicennia officinalis) and Triscelophorus acuminatus (in R. mucronata and in S. caseolaris). Surface-sterilized whole root and root bark segments of R. mucronata sampled from the mid-tide level on direct plating yielded more fungi than that of the root segments sampled from low-tide and high-tide levels. The greatest number of isolates, species richness, and diversity of fungi were shown by the whole root segments of R. mucronata from the mid-tide level. Rarefaction indices also revealed the highest expected number of species out of 150 random isolations from the mid-tide level samples of whole root and root bark segments of R. mucronata. The present study showed that fungi in mangrove roots are composed of a consortium of soil, marine, and freshwater fungi.