OCCURRENCE AND SPORULATION OF HELMINTHOSPORIUM SATIVUM P.K.B. IN THE SOIL

1931 ◽  
Vol 5 (4) ◽  
pp. 407-413 ◽  
Author(s):  
A. W. Henry
Keyword(s):  
Microscopic Examination ◽  
Soil Types ◽  
Direct Microscopic Examination ◽  
Field Soils ◽  
Helminthosporium Sativum ◽  
Unsterilized Soil ◽  
Micro Organisms

Helminthosporium sativum, one of the most prevalent fungous pathogenes affecting the roots and other parts of wheat and related grass plants, grows and fruits readily as a saprophyte on various substrata. It might therefore be expected that it would be found in abundance in the soil. Attempts to isolate it directly from field soils by plating have been successful, but only in a small percentage of the trials. Failures are apparently largely attributable to the fact that this fungus does not sporulate commonly in ordinary field soils. This has been shown by direct microscopic examination of the soil and by artificial cultures. From a study of the latter it has been found that H. sativum will sporulate quite readily on several different soil types including sand if they are sterilized, but not if they are not sterilized.The fact that soils capable of supporting sporulation of this fungus may be rendered ineffective by adding small amounts of unsterilized soil, suggests that sporulation is inhibited by the saprophytic micro-organisms of the soil. It would appear that if H. sativum occurs in the soil, it must be present chiefly in the form of mycelium. Inability to form spores probably lessens the capability of this fungus to survive as well as to multiply in the soil.

STUDIES ON FOOT AND ROOT ROT OF WHEAT: I. EFFECT OF AGE OF THE WHEAT PLANT UPON THE DEVELOPMENT OF FOOT AND ROOT ROT

1933 ◽  
Vol 8 (5) ◽  
pp. 483-491 ◽  
Author(s):  
W. C. Broadfoot
Keyword(s):  
Root Rot ◽  
Fusarium Culmorum ◽  
Wheat Plant ◽  
Seedling Stage ◽  
Critical Studies ◽  
Helminthosporium Sativum ◽  
Unsterilized Soil ◽  
Micro Organisms ◽  
Effect Of Age ◽  
Made In

Studies were made to determine whether, in sterilized inoculated soil, Marquis wheat plants became more or less susceptible during the post-seedling stage to Ophiobolus graminis, Helminthosporium sativum, and Fusarium culmorum. While it was found that the plants in the seedling stage were more susceptible than at later stages, there was, with the technique used, no evidence that the plants become more or less susceptible during the post-seedling stage. The reasons for indefinite evidence on this important question are given. In sterilized soil, in open pot culture, inoculum of O. graminis was definitely more virulent when alone than when mixed singly or in combination with H. sativum, F. culmorum or Leptosphaeria herpotrichoides. The virulence of all pathogenes mentioned decreased progressively in sterilized soil, the greatest decrease taking place during the first 40 days, after which they were only slightly pathogenic and at the end of 120 days inoculum of O. graminis was impotent. The virulence of inoculum when added to unsterilized soil was greatly reduced in contrast with that in sterilized soil, and after 10 days it was practically at a minimum. These results emphasize the necessity of protecting inoculated sterilized soil against contamination by other micro-organisms in critical studies made in soil. They also throw light on the much recognized difficulty of producing foot rot in the field by prepared inoculum added to such soil.

scholarly journals Isolation of Brucella melitensis from an abscess on the left foot of a 3-year-old infant

2009 ◽  
Vol 58 (2) ◽  
pp. 267-269 ◽  
Author(s):  
Jesús Resendiz-Sánchez ◽  
Araceli Contreras-Rodríguez ◽  
Ahidé López-Merino ◽  
Leopoldo Bravo-Guzmán ◽  
Juan Gabriel Valle-Valdez
Keyword(s):  
Microscopic Examination ◽  
Unusual Case ◽  
Brucella Melitensis ◽  
Gram Negative ◽  
Direct Microscopic Examination ◽  
Micro Organisms

An unusual case of a 3-year-old girl with a brucellar foot abscess is reported. Although direct microscopic examination of samples from the lesion did not reveal micro-organisms of any kind, a 7 day culture of caseous material yielded small colonies of Gram-negative cocobacilli in Löwenstein–Jensen medium. These were biochemically and molecularly identified as Brucella melitensis. The possibility of foot abscess being caused by Brucella should be considered in countries where brucellosis is endemic.

THE NATURAL MICROFLORA OF THE SOIL IN RELATION TO THE FOOT-ROT PROBLEM OF WHEAT

1931 ◽  
Vol 4 (1) ◽  
pp. 69-77 ◽  
Author(s):  
A. W. Henry
Keyword(s):  
Marked Effect ◽  
Black Soil ◽  
Plant Diseases ◽  
Foot Rot ◽  
Wheat Seedlings ◽  
Helminthosporium Sativum ◽  
Natural Microflora ◽  
Loam Soil ◽  
Unsterilized Soil ◽  
Inhibitive Action

In these studies the natural microflora of the black loam soil typical of the Edmonton district of Alberta had a marked inhibitive action on the development of the wheat foot-rotting fungus Helminthosporium sativum when the latter was grown directly in this soil. The severity of foot-rot infection of wheat seedlings caused by this pathogene was correspondingly reduced as a result of this action. A trace of unsterilized soil serving as a source of the saprophytic soil organisms had almost as great an influence as a relatively large amount. A similar effect on Fusarium graminearum, another fungous pathogene which causes loot-rot of wheat, is indicated.Bacteria, actinomycetes and fungi isolated from black soil each had a suppressive action on H. sativum in the soil and reduced the severity of foot-rot infection caused by it, but the fungi were considerably more effective than the bacteria and actinomycetes tested. A combination of all of these organisms produced the most marked effect and one equivalent to that produced by the organisms of unsterilized soil.The significance of the results in connection with the foot-rot problem of wheat is briefly discussed and their possible bearing on other plant diseases caused by soil-borne pathogenes is mentioned.

scholarly journals PHAGE FORMATION IN STAPHYLOCOCCUS MUSCAE CULTURES

1948 ◽  
Vol 32 (2) ◽  
pp. 203-211 ◽  
Author(s):  
Winston H. Price
Keyword(s):  
Microscopic Examination ◽  
Synthetic Medium ◽  
Bacterial Virus ◽  
Direct Microscopic Examination ◽  
Infected Cells

1. The release of S. muscae phage in veal infusion medium is correlated with lysis of the host. 2. The release of the bacterial virus in Fildes' synthetic medium occurs in a step-wise manner before observable lysis of the cells occurs. This result has been confirmed by both turbidimetric readings and direct microscopic examination of the infected cells.

scholarly journals Diagnosis of Cutaneous Leishmaniasis in Colombia: the Sampling Site within Lesions Influences the Sensitivity of Parasitologic Diagnosis

2000 ◽  
Vol 38 (10) ◽  
pp. 3768-3773 ◽  
Author(s):  
José Robinson Ramírez ◽  
Sonia Agudelo ◽  
Carlos Muskus ◽  
Juan Fernando Alzate ◽  
Christof Berberich ◽  
...  
Keyword(s):  
Cutaneous Leishmaniasis ◽  
Microscopic Examination ◽  
Sampling Site ◽  
Parasite Load ◽  
Diagnostic Methods ◽  
Active Margins ◽  
Direct Microscopic Examination ◽  
Chronic Ulcers ◽  
Pcr Method ◽  
Higher Sensitivity

Parasitologic confirmation of cutaneous leishmaniasis is obligatory before chemotherapy can be considered. Direct microscopic examination of scrapings taken from indurated borders of ulcers has been routinely used as primary method of diagnosis. In this report we compared the sensitivity of examination of dermal scrapings taken from the bottoms of ulcers (BDS) with that of dermal scrapings taken from indurated active margins of lesions (MDS) in a total of 115 patients. The sensitivities of the microscopic examination were 90.4 and 78.3% for BDS and MDS samples, respectively. When the PCR method was used with a group of 40 patients, we also observed a higher sensitivity when BDS samples were examined (80.8% in BDS samples versus 57.7% in MDS samples). The improvement of the diagnostic sensitivity in the BDS samples appears to be related to the higher parasite load and more easily detectable morphology of amastigotes in the centers of the ulcers. Other parasitologic diagnostic methods, such as culture and histopathologic examination of biopsies, are less sensitive (67.5 and 64.3%, respectively). Aspirate culture, however, was shown to be the most sensitive method for the diagnosis of patients with chronic ulcers. When microscopic examinations of both MDS and BDS samples are combined, the sensitivity of diagnosis may rise up to 94%. We therefore recommend this method as a primary routine procedure for diagnosis of cutaneous leishmaniasis.

INFLUENCE OF WILD AND CULTIVATED PLANTS ON THE MULTIPLICATION, SURVIVAL AND SPREAD OF CEREAL FOOT-ROTTING FUNGI IN THE SOIL

1935 ◽  
Vol 12 (5) ◽  
pp. 575-589 ◽  
Author(s):  
G. W. Padwick
Keyword(s):  
Bromus Inermis ◽  
Cultivated Plants ◽  
Wheat Seedlings ◽  
Helminthosporium Sativum ◽  
Soil Infestation ◽  
Loam Soil ◽  
Unsterilized Soil ◽  
Take All ◽  
Do So

Using the severity of infection of wheat seedlings as a measure of soil infestation, it is shown that susceptible grasses such as Agropyron tenerum, A. cristatum, A. repens and Bromus inermis encourage the multiplication and survival of inoculum of the take-all fungus Ophiobolus graminis in both sterilized and unsterilized soil. The same grasses also aided the survival of Helminthosporium sativum in sterilized soil. In these experiments, however, only one, namely B. inermis, appeared to favor the survival of Fusarium graminearum.The fungus O. graminis, which failed to spread laterally to any appreciable extent in bare, unsterilized black loam soil of the Edmonton district of Alberta, was able to do so when such soil was occupied by living, susceptible plants.

scholarly journals Simultaneous dermatophytosis and keratomycosis caused by Trichophyton interdigitale infection: a case report and literature review

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Mingrui Zhang ◽  
Lanxiang Jiang ◽  
Fuqiu Li ◽  
Yangchun Xu ◽  
Sha Lv ◽  
...  
Keyword(s):  
Infectious Disease ◽  
Microscopic Examination ◽  
Histopathological Examination ◽  
Trichophyton Mentagrophytes ◽  
The Body ◽  
Fungal Culture ◽  
Left Hand ◽  
Loss Of Vision ◽  
Trichophyton Interdigitale ◽  
Direct Microscopic Examination

Abstract Background Dermatophytosis is a fungal infectious disease caused by dermatophytes, which produce protease and keratinase to digest keratin, leading to the colonization, invasion, and infection of the stratum corneum of the skin, hair shafts, and nails. Trichophyton interdigitale belongs to Trichophyton mentagrophytes complex, which is the common pathogen causing dermatophytosis. Fungal keratitis, also called keratomycosis, is an infectious disease of cornea. Case presentation Here, we report a case of simultaneous dermatophytosis and keratomycosis caused by Trichophyton interdigitale. A 67-year-old man presented with extensive erythema all over the body since 4 years ago, fungal infection of left eye for 2 years, and loss of vision in the eye. These symptoms had become aggravated in the last month. Dermatological examinations showed extensive erythematous plaques with clear borders and scales, scattered red papules with ulceration, and scabs throughout the body. Onychomycosis was observed on the nails of left hand, conjunctival infection with secretion and loss of vision were noted in left eye. Hyaline septate hyphae were observed under direct microscopic examination, fungal culture and internal transcribed spacer sequencing revealed T. interdigitale. Histopathological examination suggested infectious granuloma. A diagnosis of dermatophytosis and keratomycosis caused by T. interdigitale with loss of vision in left eye was made. The patient was treated with luliconazole cream (two applications per day) and itraconazole (100 mg, BID, PO). Complete clinical remission was achieved after 1 month. Subsequently, the patient underwent left eye enucleation in the ophthalmology department. Conclusions In the present study, we reported a case of simultaneous dermatophytosis and keratomycosis caused by T. interdigitale, and reviewed the literature on corneal infection caused by Trichophyton. A total of 10 articles with 45 patients were published between 1973 and 2018. The pathogen of 27 patient were identified to species level. There were T. schoenleinii (17), T. mentagrophytes (4), T. verrucosum (3), T. rubrum (1), T. erinacei (1), and T. interdigitale (1). Five patients had corneal trauma, one had contact lens use history. Direct microscopic examination, fungal culture, and analysis of physiological characteristics were the main methods of identification. Early diagnosis and prompt treatment may help improve the management and outcomes.

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