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Inventory of aquatic microfungi diversity needs to be done as a new information about specific types found in certain waters. The objective of this study was to determine the diversity of aquatic microfungi in Madong waters, Tanjungpinang City, Riau Islands. Research on diversity of microfungi was carried out through survey methods at three stations (mangrove areas, fishing settlements and floating net cages, and coastal of Madong villages). Samples were collected by taking litters from the waters (roots, leaves, and branches of mangrove, and also seaweed). Isolation and culture process of aquatic microfungi were carried out in the laboratory. Microfungi isolates that were grown and were successfully identified were: Aspergillus sp., Epicoccum sp., Colletotrichum sp., Penicillium sp., and Stemphylium sp. Key words: aquatic microfungi, consortium, inventory, isolates, Tanjungpinang

Leaf spots on spinach were found in three greenhouses in Hokkaido and Iwate, Japan, in 2011–2012. Three isolates obtained from the lesions were classified into Stemphylium sp. Subgroups C2 and E3, based on morphology and molecular analyses. We compared the three isolates with two reference isolates belonging to Subgroup C2 from Welsh onion and leek in terms of pathogenicity. All five isolates caused leaf spot symptoms on spinach and leaf blight on Welsh onion in inoculation tests. This is the first report of spinach leaf spot caused by Stemphylium sp. Subgroups C2 and E3.

Three new methylated Δ8-pregnene steroids, stemphylisteroids A–C (1–3) were isolated from the medicinal plant Polyalthia laui-derived fungus Stemphylium sp. AZGP4-2. Their structures were elucidated by the detailed analysis of comprehensive spectroscopic data. The absolute configuration of 1 was determined by X-ray crystallographic analysis. Compound 1 show antibacterial activity against Escherichia coli with the MIC value of 6.25 μg/mL, and 2 exhibited a broad spectrum of antibacterial activities against six pathogenic bacteria with the MIC values ranging from 12.5 to 50 μg/mL. The discovery of three methylated Δ8-pregnene steroids 1–3 are a further addition to diverse and complex array of methylated steroids.

Four new anthraquinone derivatives (1-4) and four new alterporriol-type anthranoid dimers (14-17), along with 17 analogues, were isolated from the solid rice fermentation of the fungus Stemphylium sp. 33231 obtained from the mangrove Bruguiera sexangula var. rhynchopetala collected from the South China Sea. Their structures were elucidated using comprehensive spectroscopic methods. The absolute configurations of 1, 3, and 4 were determined by single-crystal X-ray diffraction of their derivatives (1a, 3b, and 4a). The absolute configurations of the chiral 17-19 were determined by comparing their CD spectra with 21. The inhibitory activities of most of the compounds against seven terrestrial pathogenic bacteria and two cancer cell lines were evaluated.

Two new stemphol sulfates, stemphol A (1) and stemphol B (2), along with known compound stemphol (3) were isolated from the EtOAc extract of the fermentation of an endophytic Stemphylium sp. 33231. The structures of these compounds were elucidated on the basis of spectroscopic analysis. The isolated compounds exhibited potent antibacterial activities against six terrestrial pathogenic bacteria with MIC values of 0.6-10 μg ml(-1). The inhibitory activities of all compounds against five cancer cell lines were evaluated.

This trial was initiated at the 8th International Asparagus Symposium in 1993 to establish a systematic evaluation for yield, spear quality and disease tolerances of commercially available asparagus cultivars. Seeds of 45 asparagus cultivars were provided by seed companies and asparagus breeders for distribution to the participants of the trial. The seed suppliers designated the climatic zones in which their respective cultivars would perform best. The trials were conducted in 19 countries by 25 researchers who have selected the cultivars they are evaluating under a uniform experimental protocol. The cultivars UC 157 F1, Gijnlim and Jersey Giant are included in all of the trials as standards. The addresses of the active trial participants and their cultivar selections are presented. The ranking of marketable spear yields and the ratings for tolerance to Puccinia asparagi, Stemphylium sp. and Botrytis sp. are presented.

Sedam dana prije blagdana Svih svetih 2012. godine, na lokalitetu naselja Miklavec uz rijeku Muru na sjeveru Međimurske županije (općina Podturen) (46°48'19"N; 16°50'43"E), primijećena je iznenadna i brza pojava promjena na laticama velikocvjetnih krizantema (bijele lopte "May Shoesmith") proizvedenih u negrijanim visokim tunelima površine 300 m2. Promjene su bile vidljive na odrezanim biljkama u spremištu. Pregledom je isključena moguća fitotoksičnost sredstva za zaštitu bilja te napad grinja - npr. običnoga crvenoga pauka (Tetranychus urticae) i/ili kukaca - npr. kalifornijskoga tripsa (Frankliniella occidentalis). Prema tipičnim simptomima, mikroskopskim pregledom i zabilježenim meteorološkim uvjetima mjernim uređajem "iMetos" tijekom listopada 2012. na području općine Podturen, zaključili smo da je to zaraza dosad nepoznatom bolešću latica krizantema u našoj zemlji kojoj je uzročnik Stemphylium sp. Za suzbijanje te bolesti latica krizantema preporučili smo da se odmah nakon pojave prvih simptoma primijeni u finim česticama iznad biljaka fludioksonil & ciprodinil (Switch WG 0,08 %), što je bila vrlo učinkovita mjera kemijske zaštite., A new disease of chrysanthemum causing ray speck was found in north part of Medjimurje region (Miklavec city near river Mum) (46°48'19"N; 16°50'43"E). In the beginning of last week in October 2012, when chrysanthemums cv. "white ball" (May Shoesmith) harvested for flower arrangements, small reddish-brown lesions (0.1 mm) were observed on the ray florets. Disease was more visible on plants in storage and less in plastic greenhouse. Meteorological data on this locality were very favorable for disease epidemiology, because of rain (83,8 mm per month), fog and dew (9.380 minute free moisture per month in leaf wetness sensor), high relative humidity (average month value 90,6 %), and optimal temperature (data from "iMetos") (46°45'60"N; 16°56'82"E). The causal fungus was identified as Stemphylium sp. based on typical symptom (the necrotic specks do not enlarge after incubation), and microscopy examination. For chemical control very effective was fungicide Switch WG (fludioxonil & cyprodinil), applied after first visible damage. This is the first report of chrysanthemum ray speck caused by Stemphylium sp. in Croatia.

Mestrado em Engenharia Agronómica - Hortofruticultura e Viticultura - Instituto Superior de Agronomia This study aims to contribute to the diagnosis of brown spot of spitzkool cabbages, clarifying symptoms associated with the disease and its evolution in the final stage of field. We identified the causative agent of the disease as Stemphylium sp. by classical methods of mycology and sequencing fragments amplified by PCR of DNA purified from cabbage leaves with injuries, which has shown very significant homologies with the fungal genus Stemphylium. We tested the biological efficacy of six fungicides for Stemphylium sp. in in vitro studies. The mycelial growth was inhibited by more evidence fungicide pyraclostrobin + boscalid, pyraclostrobin and difenoconazole + dimethomorph. Based on these results, were selected pyraclostrobin and boscalid + difenoconazole to assess inhibition of spore germination. The fungicide used the first showed efficacy. We evaluated the disease from its onset in a field production, in field subjected to conventional treatments scheme and control field treated with water and refrigerated conditions. The disease was detectable one week before the harvest in the field treated with water, but over time disease developed in a stronger manner in the field treated with fungicides. During storage, room temperature conducted to the development of more spots in the cabbages that refrigeration conditions.

A survey conducted in the market gardens of Lome (Togo) have allowed to record and identify the main diseases which limit vegetable production. Organ rot and leaves spot are among the most frequent affection, respectively 20% and 17.5% of the cultivated vegetables. Small pieces of cankered sweet pepper leaves, cankered lettuce leaves and rotten onion bulb cultuved on Sabouraud chloramphenicol agar and on Potato Dextrose Agar+chloramphenicol have allowed to describe three (3) fungal diseases as lettuce and sweet pepper alternariose caused by Alternaria sp., onion bulb rot caused by Fusarium and sweet pepper stemphyliose caused by Stemphylium sp. Preventive measures will be find in improvement of gardening practices. Une prospection realisee dans les exploitations maraicheres de la ville de Lome (Togo) a permis d’identifier les pourritures d’organes et les taches foliaires comme etant les principales affections qui freinent la production des cultures maraicheres. Elles affectent respectivement 20% et 17,5% des legumes cultives. L’isolement et l’identification des micromycetes responsables sont faits a partir des cultures de fragments de bulbes d’oignon pourris, de feuilles necrosees de poivron et de laitue sur gelose Sabouraud chloramphenicol et sur Potato Dextrose Agar chloramphenicol. Trois maladies fongiques sont decrites : l’alternariose de la laitue et du poivron causee par Alternaria sp., le pourridie fusarien des bulbes d’oignon du a Fusarium sp. et la stemphyliose du poivron dont l’agent pathogene est Stemphylium sp. Des mesures preventives a prendre resident dans l’amelioration des pratiques culturales

Three types of lesion occur on spears of asparagus (Asparagus officinalis) infected with a Stemphylium sp. : limited, spreading, and fleck. The pathogen enters the host via stomata. Host cellular changes are restricted to the epidermis and cortex. In the limited lesion type of infection, there is a rapid cytoplasmic degeneration of host cells, beginning close to the penetrating hyphae, but eventually also occurring at a distance from these. Electron-dense material accumulates in the intercellular spaces and envelops the hyphae. Hyphae, the contents of which become disorganised, occupy only a small part of the central area of the lesion. The spreading type of lesion is much larger than the limited type. Electron-dense material is absent, and hyphae ramify throughout the intercellular spaces of the lesion. The third type, a fleck lesion, develops in response to inoculation of Stemphylium isolates nonpathogenic to asparagus. Electron-dense material is produced before stomatal penetration is complete, and hyphae fail to penetrate beyond the substomatal cavity. Only a few host cells are degraded. Application of concentrated culture fluids of a pathogenic Stemphylium isolate to excised asparagus spears failed to produce disease symptoms on either wounded or unwounded tissue.

(1988). Isolation and Conformation of (2Z,4E)-(+)-4′-Hydroxy- γ-ionylideneacetic Acid as a Germination-suppressive Substance from Stemphylium sp. Agricultural and Biological Chemistry: Vol. 52, No. 6, pp. 1625-1628.

A severe leaf spot disease on the flower stalks of seed onions is caused by a Stemphylium sp. which attacks the seed-stalk, weakening it and finally causing its collapse. The concept of applying a fungicide by a two-directional air-assisted placement spraying technique was investigated in the laboratory and subsequently proven in the field. It was shown that disease control was linear with the fungicide-protected area. Disease severity was reduced by ∼ 75% by the air-assisted placement spraying compared with ∼ 30% for cloud spraying. The results also indicated that the infection area was linearly proportional to the calculated seed yield.

The microhabitats of these mites are in the litter layer of soils, where they feed vigorously on certain fungi. In the laboratory, at 20° C. and approximately 90% r.h., both species required slightly more than 2 months for their complete development. M. montana used the fungi Trichoderma koningi, Cladasporium cladosporioides , and Stemphylium sp. as food, while E. nervosa developed from egg to adult using T. koningi only. During the winter, when ground water was frozen, both species could be found in the upper 3 inches of soil, E. nervosa as adults and M. montana as tritonymphs and adults. E. nervosa produces one or two eggs, M. montana up to four eggs at a single time, and both species oviposit from mid-spring to late fall; each probably has one generation a year in the field. E. nervosa is most easily recognized when captured alive by its behavioral pattern of shaking leg I three or four times at each step in walking.