Addition and reexamination of Japanese species belonging to the genus <Emphasis Type="Italic">Cercospora</Emphasis> and allied genera. VI. Four <Emphasis Type="Italic">Pseudocercospora</Emphasis> species from Ohshima Island,Tokyo

Four fungi belonging to the genus Pseudocercospora were collected from Ohshima Island, which has commonly been called Izu-ohshima, Tokyo. Among them, two on Helwingia japonica and on Stachyurus praecox var. matsuzakii are recognized as new species, and named P. izuohshimensis and P. hachijokibushi, respectively. Styrax japonica var. jippei-kawamurae was newly added to the host list of P. fukuokaensis. Presence of P. myrticola in Japan was reconfirmed in examining a fresh diseased material on Myrtus communis.     

Effects of arbuscular mycorrhizal fungi and soil developmental stages on herbaceous plants growing in the early stage of primary succession on Mount Fuji

A pot culture experiment was conducted to examine the effects of arbuscular mycorrhizal (AM) fungi and soil developmental stages on the growth and nutrient absorption of pioneer plants growing in the early stage of primary succession on Mt. Fuji. Four herbaceous plants, Polygonum cuspidatum (Polygonaceae), Miscanthus oligostachyus (Gramineae), Aster ageratoides var. ovatus (Compositae), and Hedysarum vicioides (Leguminosae), were grown from seed in soils collected from two different successional stages, bare ground and an herbaceous plant community. Spores of indigenous AM fungi collected from the herbaceous plant community were used as inoculum. The initial colonizer P. cuspidatum showed very low levels of AM colonization (<0.4%), whereas the average AM colonization levels of M. oligostachyus, A. ageratoides var. ovatus, and H. vicioides were within the range of 13–49%. AM fungi had positive effects on the growth and N acquisition of the leguminous species (H. vicioides) irrespective of soil developmental stages. In contrast, AM colonization did not increase the plant dry weight and N content of the non-leguminous species (P. cuspidatum, M. oligostachyus, and A. ageratoides var. ovatus) in both soil developmental stages. A positive effect of AM colonization on P content was observed in M. oligostachyus, A. ageratoides var. ovatus, and H. vicioides only in soil collected from the herbaceous plant community. P. cuspidatum showed no or a negative response to AM colonization in all cases. These results suggest that the effect of AM fungi on plant growth depends more on the plant species than soil developmental stages in the early stage of primary succession in this volcanic area.     

Antagonistic Activity of Neocosmospora vasinfecta var. africana (von Arx) Cannon & Hawksworth against Soil-borne Fungi

An isolate of Neocosmospora vasinfecta var. africana (F-2) was assayed for its antagonistic activity against 15 soil-borne fungi; 14 of them were important plant pathogens. The fungus exhibited a strong antibiotic effect against most of the fungi under test. While Pythium debaryanum, Macrophomina phaseolina, Phytophthora capsici, Sclerotinia sclerotiorum, Cochliobolus sativus and Alternaria alternata showed a very high degree of sensitivity as evidenced by the respectivezones of inhibition caused by the antagonist, Phoma betae, Rhizoctonia solani and Verticillium dahliae proved to be the most resistant. A mutual antibiosis existed between N. vasinfecta var. africana and five of the test fungi. The culture filtrate of the antagonist, diluted ten times with PDA, suppressed the mycelial growth of P. debaryanum and P. capsici completely. Whereas in this test R. solani proved to be the least sensitive, the remaining test fungi showed some differences in their susceptibility, but in any case their growth was inhibited significantly as compared to the controls.     

Effect of osmotic potential on the growth of Gaeumannomyces graminis and Phialophora spp.

The linear growth of 10 isolates each of Gaeumannomyces graminis var. graminis, G. graminis var. tritici and Phialophora graminicola and five isolates each of G. graminis var. avenae and a lobed-hyphopodiate Phialophora sp. was studied on osmotically adjusted agar at 20 °C. While most isolates of G. graminis var. avenae ceased growing at osmotic potentials of -60 bars (1 bar = 10⁵ Pa), six out of 10 isolates of G. graminis var. tritici grew at that potential. The growth of all isolates of G. graminis var. tritici and var. avenae ceased at -70 bars. In contrast, four out of 10 isolates of P. graminicola grew at -70 bars, but all stopped growing at -80 bars. Most of the isolates of G. graminis var. graminis and the lobed-hyphopodiate Phialophora sp. grew at -70 bars while three out of 10 isolates of G. graminis var. graminis and one out of five isolates of the lobed-hyphopodiate Phialophora sp. were capable of growth at -80 bars. None of the fungi grew at -90 bars. Detailed studies of the growth of two or three isolates each of the five fungi at 10, 20, 30 and 35 °C were carried out on osmotic agar controlled by the addition of either sodium chloride or potassium chloride. In general, similar reductions in growth occurred with decreasing osmotic potential regardless of the solute used. At 10 and 20 °C., all three isolates of P. graminicola showed optimal growth at about -5 bars while the other fungi grew fastest at -1²middot; bars. At 30 °C., one isolate of the lobed hyphopodiate Phialophora sp. and two isolates each of P. graminicola, G. graminis var. tritici and G. graminis var. avenae grew optimally at osmotic potentials of -10 to -15 bars. The other isolate of the Phialophora sp. and two isolates of G. graminis var. graminis studied grew optimally at the highest potential (-1·2 bars). However, at 35 °C the last three fungi exhibited optimal growth at osmotic potentials of-10 to -20 bars. The ecological significance of these results is discussed in relation to cross-protection against the take-all fungi by the avirulent fungi.     

Quantities and types of ectomycorrhizal and endophytic fungi associated with Betula platyphylla var. japonica seedlings during the initial stage of establishment of vegetation after disturbance

Ectomycorrhizal and endophytic fungi of Betula platyphylla Sukatchev var. japonica Hara seedlings were investigated by bioassay using soils from sites where the surface layer had been removed by destructive disturbances. Soil samples were taken from sites A, B, C and D, where 1, 2–3, 4–5, and 7–8 years, respectively had passed since disturbance. Naturally regenerated B. platyphylla var. japonica seedlings grew at sites C and D, but not at sites A or B. The percentages of ectomycorrhizal formation in seedlings were significantly lower in the soils from site A (4%) and site B (13%), compared to those in the soils from site C (53%) and site D (37%). The numbers of ectomycorrhizal morphologic types in sites A, B, C, and D were eight, five, one, and seven, respectively. The same dominant type of ectomycorrhiza was found in sites C and D, and this type was different from those in sites A and B. The frequencies of colonization of seedling roots by endophytic fungi, especially Mycelium radicis atrovirens Melin (MRA) in soils from sites A and B were 31 and 33%, respectively; these frequencies were significantly higher than those for site C (0%) and site D (2%). During the initial stage of establishment of vegetation following disturbance, the quantities and types of ectomycorrhizal fungi in the field that have the potential to associate with B. platyphylla var. japonica might rapidly change after invasion of the host plant. Ectomycorrhizal fungi seemed to compete with endophytic MRA fungi for colonization of the roots of B. platyphylla var. japonica seedlings.     

SUBMERGENCE EXPERIMENTS ON NINE SPECIES OF SEMI-AQUATIC POLYGONUM

Cloning experiments were carried out in growth chambers to determine responses of members of the genus Polygonum (sect. Persicaria) to aquatic submergence. By using both external morphology and anatomical modifications, comparisons were made among 23 populations with respect to their preadaptations after a rise in water level. Varieties of P. amphibium L. responded quite differently to submergence, offering more evidence to the theory that there is a cline of phenotypic plasticity in the species which corresponds roughly with the gradient in morphology. Other than P. amphibium, the species most well adapted to aquatic conditions was P. densiflorum Meisn., a member of the P. punctatum Ell. complex. Populations of P. hydropiperoides Michx. showed a dichotomy of response which appeared to correlate with the habitats in which they were collected. A few species of Polygonum did not survive well after inundation, but most were capable of underwater growth, and were at least half as well adapted to aquatic conditions as was the most plastic variety, P. amphibium var. stipulaceum Colem.     

Effects of isolates of ectomycorrhizal fungi and endophytic Mycelium radicis atrovirens that were dominant in soil from disturbed sites on growth of Betula platyphylla var. japonica seedlings

Effects of ectomycorrhizal fungi and endophytic Mycelium radicis atrovirens Melin (MRA) on growth of Betula platyphylla var. japonica seedlings were investigated under aseptic culture conditions. Three isolates of ectomycorrhizal fungi and two isolates of MRA were used. One MRA isolate was Phialocephala fortinii. Previous field work revealed that these isolates were dominant on the roots of B. platyphylla var. japonica seedlings grown in a mineral subsoil that had been exposed by the removal of surface soil. After a 100-day incubation, the growth of the seedlings was significantly enhanced by the colonization of these ectomycorrhizal fungal isolates as compared with uninoculated seedlings. In contrast, the growth of seedlings was retarded by the colonization of the MRA isolates. The growth of seedlings that were co-inoculated with ectomycorrhizal fungi and MRA was similar to that of uninoculated seedlings in most cases. These results suggest that ectomycorrhizal fungi have a beneficial effect on the growth of B. platyphylla var. japonica seedlings and that they suppress the deleterious effect of MRA. Thus, these ectomycorrhizal fungi probably have an important role in establishing B. platyphylla var. japonica seedlings during the initial stage of re-vegetation following site disturbance by the removal of surface soil.     

Contribution of the mesophilic fungi of different spices in Egypt

Thirty-eight genera and 81 species of fungi were isolated and identified from 120 samples of 24 kinds of spices collected from different places at Assiut Governorate, Egypt. Predominant genera wereAspergillus (25 species) andPenicillium (7 species) of whichA. flavus, A. niger, A. ochraceus, A. fumigatus, A. flavus var.columnaris, A. terreus, P. chrysogenum andP. corylophilum were the most commonly occurring.     

Control of Ophiobolus patch in Agrostis turf using avirulent fungi and take-all suppressive soils in pot experiments

The incorporation of avirulent fungi such as Gaeumannomyces graminis var. graminis, an avirulent isolate of G. graminis var. tritici, a Phialophora sp. with lobed hyphopodia synonymous with Phialophora radiciola var. radicicola sensu Deacon and P. radicicola var. graminicola at the time of seeding Agrostis turf in pots of sterilised soil completely controlled Ophiobolus patch disease. The addition of a 5 mm layer of take-all suppressive (TAS) soils, artifically developed by the repeated addition of live mycelium of the varieties avenae, tritici and graminis of G. graminis to soil, controlled the disease to a lesser extent. However, a 20 mm layer of a TAS soil developed from live mycelium of G. g. avenae almost completely suppressed the disease. A survey of 66 golf and bowling greens in four states of Australia showed that P. r. graminicola was the most prevalent avirulent fungus.     

Molecular identification of the mycorrhizal fungi of the epiparasitic plant Monotropastrum humile var. glaberrimum (Ericaceae)

Achlorophyllous monotropoid plants (Monotropoideae, Ericaceae) are epiparasites that obtain all of their carbon from their host plants via connections with mycorrhizal fungi. The mycorrhizal fungi of the epiparasitic monotropoid Monotropastrum humile var. glaberrima were identified based on mitochondrial, large ribosomal DNA sequences, and were compared with those of another variety, M. humile var. humile. The fungi that inhabit M. humile var. glaberrimum belong to the Thelephoraceae, whereas that of M. humile var. humile is a member of the Russulaceae. Two explanations are possible for this phenomenon: a misunderstanding of the taxonomic position of M. humile var. glaberrimum, or a change in the fungal partner within the Monotropastrum.     

Toxic aspergilli from pistachio nuts

Pistachio nut samples taken during various stages of development from orchards in Iran, showed that contamination with fungi occurred mainly during the later stages of nut development. Members of the genera Aspergillus and Penicillium occurred most frequently. Of the Aspergilli, the species A. niger, A. flavus and A. fischeri var. spinosus occurred most frequently, followed by A. terreus, A. tamarii and A. nidulans. Twenty-two isolates comprising 13 species were tested for toxicity to ducklings. Isolates of known toxic fungi included A. flavus, A. niger, A. parasiticus, A. ochraceus, A. versicolor, A. nidulans and A. terreus. The toxicity of A. fischeri var. spinosus is reported. Chemical analysis showed that all isolates of A. flavus and A. parasiticus produced aflatoxin B₁, the isolates of A. versicolor and A. nidulans produced sterigmatocystin while the toxic isolate of A. ochraceus did not produce ochratoxins.Toxic fungi have been shown to occur in a variety of nuts (4), (5), (11), (12), (13), (15), (18), (20), (21). Aflatoxin contamination of pistachio nuts has been reported and has in the past led to the rejection of consignments of Iranian pistachio nuts (1). In Iran, pistachio nuts are produced mainly in the south eastern provinces (Kerman & Zahedan) and to a limited extent in the Northern part (Kazvin & Damghan). In 1975 it was estimated (7) that there were some 24 million pistachio trees in Iran, of which 60% were situated in Rafsanjan, Kerman (Table 1). Economic considerations as well as the potential health hazard posed by aflatoxin-contaminated nuts, prompted the University of Isfahan to initiate a study of various aspects of the mycotoxin problem in pistachio nuts.     

Saprophytic survival of Gaeumannomyces graminis and Phialophora spp. at various temperature-moisture regimes

The saprophytic survival of the pathogen, Gaeumannomyces graminis var. tritici and two isolates each of three avirulent fungi, G. graminis var. graminis, Phialophora graminicola and a lobed-hyphopodiate Phialophora sp. was studied in two soil types under controlled temperature and moisture conditions in the laboratory. In general, the fungi survived longest in the cool, dry soil (15°C, < -10 MPa) followed by the warm dry soil (30°C, < -10 MPa). All the fungi were virtually eliminated from the warm, moist soil (30°C, -0.3 MPa) after 3 months. Survival was intermediate under cool, moist conditions (15°C, -0.3 MPa). Under cool, moist conditions, G. graminis var. graminis survived better than the other three fungi in the first 3 months in both soil types and continued to do so for a further 3 months in one soil. Both isolates of the lobed-hyphopodiate Phialophora sp. survived poorly in the two soil types being almost eliminated after 3 months. There were considerable differences between the survival of the two isolates each of G. graminis var. graminis and P. graminicola, especially under cool, moist conditions. Of the six avirulent isolates studied, one isolate of G. graminis var. graminis (DAR24167) survived best under the three temperature-moisture regimes which showed differences. It also survived better than the take-all fungus under moist, cool conditions and at a comparable rate under dry conditions. Therefore, this variation in survival should be considered when selecting antagonists for the biological control of take-all.     

Effect of Sparkill and Tafaban insecticides on the mycoflora of maize plant in Upper Egypt

Sparkill (25% Cypermethrin) and Tafaban (48% Chlorpyrifos) insecticides were used in the treatment of maize plants in the field to investigate the effect of these compounds on fungi associated with roots and shoots of maize as well as on soil fungi. Generally, the two insecticides exhibited an inhibitive effect on the total and individual counts of glucophilic fungi after different periods of treatment except in some cases the counts were not affected or promoted compared with the control samples. Fungal genera and species associated with roots and shoots of maize plants were isolated from untreated plants as control and then compared with those isolated from plants treated with different doses of insecticides. The most common fungal species recovered from soil and different parts of plants were Alternaria alternata, Aspergillus flavus, A. fumigatus, A. niger, A. terreus, Cochliobolus spicifer, Emericella nidulans, E. nidulans var. lata, Fusarium oxysporum, Gibberella fujikuroi, Nectria haematococca, Penicillium chrysogenum, P. funiculosum, P. oxalicum and Rhizopus stolonifer.     

Johnkarlingia,a new genus of the synchytriaceae

A chytridiaceous fungous species was found parasitic in the roots of cauliflower (Brassica oleracea L. var. botrytis) and cabbage (Brassica oleracea L. var. capitata) in the heavy soil fields of Varanasi, U.P. The morphology of resting sporangia and life cycle of the pathogen revealed that no fungus species has hitherto been described befitting its developmental pattern. A new genus Johnkarlingia Pavgi & Singh has been proposed to accommodate the fungus with Johnkarlingia brassicae Singh & Pavgi as its type species. The taxonomy and affinities of the genus are discussed.     

国产合瓣花植物名称的后选模式指定——Ⅲ. 玄参科、紫葳科和苦苣苔科

在整理保存于中国科学院植物研究所中国国家植物标本馆(PE)的国产合瓣花植物模式标本时,根据《国际藻类、菌类、植物命名法规》(墨尔本法规)规则9.5,发现在玄参科中的阿拉善马先蒿、中国马先蒿、反曲马先蒿、红毛马先蒿、粗野马先蒿、扭旋马先蒿和四川婆婆纳、在紫葳科中的密生波罗花、角蒿、烟色叶角蒿和黄花角蒿、在苦苣苔科中的东川粗筒苣苔、滇川唇柱苣苔和羽裂全盏苣苔名称的模式为合模式。遵照规则8.1、9.11和9.12,以及辅则9A.3的精神,对这14个名称做出后选模式指定。     

Detection of Pseudocercosporella herpotrichoides (Fron) Deighton in Wheat by Indirect ELISA

An indirect ELISA for quantitative detection of P. herpotrichoides in fections in wheat is presented. All tested isolates of the virulent varieties P. herpotrichoides var. herpotrichoides, P. h. var. acuformis or the W- and R-type react on a high level in the test, while the less virulent P. anguioides is assessed only with 40% and the avirulent P. aestiva with 20% of the homologous reaction. No crossreactions occur with extracts of 11 other species of in, vitro cultivated fungi nor with plant material infected with other pathogens. The infection profile throughout the leaf-sheaths was clearly reflected by ELISA. The examination of 24 stembase samples from the field showed that the values assessed by ELISA correlate well also with the disease indices of naturally infected plant material.     

三种松树内生真菌的分离鉴定及其对红脂大小蠹伴生真菌的拮抗作用

【背景】松树的内生真菌会影响红脂大小蠹及其伴生真菌的生长及扩散,从而影响红脂大小蠹的入侵。【目的】掌握赤峰地区红脂大小蠹寄主树种内生真菌的物种多样性,筛选对其伴生菌有拮抗作用的菌株,为红脂大小蠹的生物防治提供资源。【方法】采用组织分离法、形态学鉴定和internal transcribed spacer (ITS)序列分析相结合的方法对红脂大小蠹寄主树种油松、樟子松和潜在寄主落叶松进行内生真菌多样性研究,并用两点对峙法进行拮抗菌株筛选。【结果】松树内生真菌鉴定为2门6纲10目18科19属,其中落叶松韧皮部分离到的内生真菌数量最多,为39株,隶属于9属12种,真菌检出率为43.33%;油松次之,为30株,隶属于7属8种,真菌检出率为33.33%;樟子松最少,为29株,隶属于10属13种,真菌检出率为32.22%。3个树种的内生真菌相似性较低,无共有的菌种,青霉属(Penicillium)和篮状菌属(Talaromyces)是唯二的共有菌属,且青霉属在3个树种中均为优势菌属。平板对峙结果表明90%以上的树木内生真菌均能够与伴生真菌形成稳定的对峙,抑制率在50%-86%之间,且Phialocephala sp.和Pochonia bulbillosa对伴生菌的抑制率能高达93.7%。【结论】松树韧皮部的内生真菌具有较高的生防潜力,Phialocephala sp.和P. bulbillosa对红脂大小蠹伴生菌有较好的抑制效果,可作为红脂大小蠹的生防资源。     

A new point of view on the taxonomy ofPottia starckeana agg. (Musci,Pottiaceae)

A new taxonomic treatment is proposed for thePottia starckeana species complex. The peristome development is not considered to be a useful feature to separate the taxa. On the basis of spore morphology only two species are accepted:P. starckeana, with spores wavy in outline, andP. davalliana, with variously-shaped and developed processes on the spores.Pottia starckeana var.brachyoda is reduced to synonymy withP. starckeana; P. conica andP. commutata are treated as synonyms ofP. davalliana. The speciesP. mutica, P. affinis, P. salina, P. microphylla, P. texana, andP. arizonica (included var.mucronulata) are considered taxa of doubtful affinity, as they have spore features intermediate between the two spore types established for the group. The identity ofP. appertii andP. recurvifolia has not been elucidated because the type material has been destroyed.     

Taxonomic position of a Chinese <Emphasis Type="Italic">Pleurotus</Emphasis> “Bai-Ling-Gu”: it belongs to <Emphasis Type="Italic">Pleurotus eryngii</Emphasis> (DC.: Fr.) Quél. and evolved independently in China

The Chinese Bai-Ling-Gu is a mushroom named Pleurotus eryngii var. tuoliensis C.J. Mou. This species has been identified as P. nebrodensis or P. eryngii var. nebrodensis. We examined its taxonomic position by analysis of mating, cultivation, and rDNA sequences, and concluded as follows. (1) Bai-Ling-Gu mated with P. eryngii var. eryngii, and the F₁ and F₂ formed fruit bodies. (2) Bai-Ling-Gu mated with P. eryngii var. ferulae, and the F₁ formed fruit bodies. (3) In the di-mon mating test, P. eryngii var. nebrodensis from Sicily mated with monokaryons of P. eryngii var. eryngii but mated hardly at all with those of Bai-Ling-Gu and P. eryngii var. ferulae. The di-mon mating pattern of Bai-Ling-Gu resembled those of P. eryngii var. ferulae. (4) The partial sequences of rDNA ITS1 and IGS1 from the epitype of P. nebrodensis were identical with those from P. eryngii var. nebrodensis from Sicily but differed from those from Bai-Ling-Gu. (5) The strains of P. eryngii var. eryngii and P. eryngii var. ferulae were in a group, the strains of P. eryngii var. nebrodensis from Sicily were in another group, and the strains of Bai-Ling-Gu were in the other group in both the phylogenetic trees based on the ITS1 and the IGS1 sequences. These results led to the conclusion that Bai-Ling-Gu is a variety of P. eryngii and evolved independently in China. It is satisfactory to identify Bai-Ling-Gu with P. eryngii var. tuoliensis C.J. Mou.     

Pink root rot,a revised name of brown root rot of gentian,and the causal fungi,Pyrenochaeta gentianicola sp. nov. andP. terrestris in Japan

Cultivated gentian (Gentiana scabra var.buergeri) has been seriously damaged by pink root rot since the 1970s. Diseased plants finally collapse after wilting and stunting. More than 40 fungal genera were found to be associated with roots of mature and immature diseased plants or seeds. Among these fungi,Pyrenochaeta gentianicola sp. nov. andP. terrestris were almost always associated with the diseased plants. Their morphologies and temperature responses were compared, and their pathogenicity was also demonstrated by artificial inoculation tests.Part of this work was conducted at the National Institute of Agricultural Sciences (presently National Institute of Agro-Environmental Sciences), Tsukuba S.C., Ibaraki 305, Japan by T. Watanabe.