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41.
Joseph J. Cooney Mark M. Doolittle Otto Grahl-Nielsen Inger M. Haaland Paul W. Kirk Jr 《Journal of industrial microbiology & biotechnology》1993,12(6):373-378
Summary Ten obligate marine fungi have as their principal fatty acids 160, 180, 181n9 and 182n6. The fatty acids ranged from 14 to 22 carbons, completely dominated by those with even numbers of carbons. The amount of unsaturated fatty acids varied between 35% and 80%. Each isolate contained small amounts of the acids 183n3 and 204n6. Branched, hydroxy- or cyclic fatty acids were not detected. Multivariate statistical, i.e. principal component analysis, showed that all ten strains could be distinguished on the basis of their fatty acid composition. These results indicate that the marine fungi do not have an unusual fatty acid composition and suggest that chemometric, multivariate analysis might be employed to confirm taxonomic relationships among these organisms. 相似文献
42.
在对新疆及海南岛的捕食线虫真菌的调查中发现2个真菌与已报道的孤孢属的真菌不同,确定为新种——长梗孤孢菌(Monacrosporium longiphorum Liu et Lu sp. nov.)和小舟形孤孢菌(Monacrosporium microscaphoides Liu et Lu sp. nov.)。长梗孤孢菌主要特征为分生孢子梗较长,448-660 μm,分生孢子3-4个分隔,39-65(54) × 13-22(18) μm。小舟形孤孢菌主要特征为孢子较小,0-3个分隔,以2个分隔为主,23-39(29) × 8-15.5(12)μm。在老的培养物中可见球形串生的厚垣孢子。 相似文献
43.
Anders Michelsen 《Mycorrhiza》1993,4(1):11-15
Roots of 28 species of epiphytic vascular plants were collected on tree trunks and branches at six afromontane forest sites between 1700 and 3300 m above sea level in Bale Mountains National Park, Ethiopia. Seven of the 28 epiphyte species were colonized by vesicular-arbuscular mycorrhizal fungi (VAM). Mycorrhizal colonization only occurred at two of the six sites examined, at 2900 m and 3300 m, but more than one type of VAM endophyte was present in each case. Three facultative epiphytic species were all highly colonized by VAM on the forest floor, whereas roots from epiphytic habitats were weakly colonized. No correlations were found between VAM colonization, fine root diameter and root hair length, but VAM colonization and root hair abundance were negatively correlated. The lack of VAM colonization of potential, epiphytic host species at the majority of the sites examined points to the dispersal of VAM propagules as the factor limiting mycorrhizal colonization of epiphytic habitats. It is suggested that root systems of hemiepiphytic tree species serve as corridors between forest floor and tree trunks through which VAM may spread via hyphal growth. 相似文献
44.
S. E. Bellgard 《Mycorrhiza》1993,3(1):19-24
The formation of vesicular-arbuscular mycorrhizae (VAM) in intact soil profiles from two sites in southeastern Australia were measured at two depths using a bioassay grown in intact soil cores. Intact soil cores were taken from (1) topsoil (0–15 cm) and (2) subsoil (15–30 cm) four times during 1990. Seeds of Acacialinifolia (Vent.) Willd. (Mimosaceae) were sown into the cores and plants harvested 8 and 12 weeks after sowing. For 1990, at both sites and in all seasons, VAM most readily developed in the roots of seedlings of A. linifolia grown in topsoil. Limited VAM occurred in roots grown in subsoil cores. Most colonisation of roots by VAM occurred from cores collected during spring and summer. Spore numbers were quantified for each site and depth by wet-sieving 100-g samples of air-dried soil and counting turgid spores containing oil droplets. Three types of spores were found in the soils. Few spores were extracted from all soils sampled, and for the most abundant of the spore types at least twice as many spores occurred in the topsoil than in the subsoil for all seasons examined. As most of the propagules that initiate VAM infection were observed in the topsoil, disturbances which involve the removal and storage of the top 15 cm will adversely affected these fungi. 相似文献
45.
通过对文字衣科黑文衣属形态学、解剖学、化学与分子生物学的研究,发现中国新记录种1种,即变黄黑文衣(Phaeographis flavescens Dal-Forno&Eliasaro),该种主要特征为地衣体壳状,表面浅黄绿色,无光泽,光滑;子囊盘弯曲,多分支,聚生于假子座中;盘缘黑色,相邻线盘之间有小缝隙,盘面较平坦,黑色,覆有白色粉霜;子囊层无色透明,侧丝顶端分支;子囊含8个子囊孢子;子囊孢子褐色,横隔透镜型,(4~)6胞室,大小19~25.5μm×6~7μm,I+紫红色。该种分布于云南和福建,该研究丰富了对中国黑文衣属物种组成与分布的认知。 相似文献
46.
Cytokinins are phytohormones that participate in regulation of all aspects of plant growth and development, including response to biotic agents. Fungi of different taxonomic and trophic groups synthesize cytokinins, employing them for interaction with plants, both friendly and hostile. They also appear to be able to manipulate the host plant genes of cytokinin biosynthesis and metabolism to their own benefit. In this review, we analyzed the data about changes in the level and composition of cytokinin pool under fungi influence, the effect of exogenous hormones on the growth of fungi in culture and in situ, changes in the physiology and metabolism of fungi due to genetic transformations related to cytokinins. The possible role of cytokinins in the regulation of macromycete development is discussed as well. The pattern of cytokinin dynamics allow us to consider the hormones of this class as potential regulators of fungi growth. Further explore of fungal cytokinins is essential to improve biotechnology using fungi as raw materials for medicine and agricultural production. 相似文献
47.
48.
The ectendomycorrhizal fungiWilcoxina mikolae isolates CSY-14 and RMD-947 andW. rehmii isolate CSY-85 were grown in pure culture under iron-limiting conditions. All three isolates tested positive for siderophore formation using both the ferric perchlorate assay and a sensitive HPLC iron-binding assay. A peptide siderophore was isolated from the culture medium by HPLC and shown to contain the amino acids serine, glycine and ornithine in a 1:2:3 ratio. This siderophore was identified as ferricrocin on the basis of electrospray mass spectroscopy and its co-chromatography in two different HPLC systems with ferricrocin isolated fromAspergillus fumigatus. Ferricrocin was the only siderophore isolated from theseWilcoxina cultures. This is the first report of siderophore formation by ectendomycorrhizal fungi. 相似文献
49.
Atelocauda koae, a rust of the native HawaiianAcacia koa, is considered as a demicyclic species, having spermogonial, aecial, and telial states, but is unusual in production of aeciospores
simultaneously with teliospores rather than consecutively. Host inoculation with spores of each state separately confirmed
that the life cycle was perpetuated by the telial state, but the aeciospores, while capable of germination and stomal penetration,
did not produce detectable infection. This rust therefore behaves as a microcyclic species, and appears to be in evolutionary
transition toward this reduced state. Teliospores produced vestigial, permanently attached basidiosopores which germinated
to produce infective hyphae. The hyphae entered the host either through stomata or penetrated the epidermis directly, with
the latter method being more common. Unusual nuclear associated with teliospore germination, in which meiosis occurs in more
than one diploid nucleus was observed, in confirmation of an earlier study. 相似文献