Inhibition Effects of Silver Nanoparticles against Powdery Mildews on Cucumber and Pumpkin

Powdery mildew is one of the most devastating diseases in cucurbits. Crop yield can decline as the disease severity increases. In this study, we evaluated the effect of silver nanoparticles against powdery mildew under different cultivation conditions in vitro and in vivo . Silver nanoparticles (WA-CV-WA13B) at various concentrations were applied before and after disease outbreak in plants to determine antifungal activities. In the field tests, the application of 100 ppm silver nanoparticles showed the highest inhibition rate for both before and after the outbreak of disease on cucumbers and pumpkins. Also, the application of 100 ppm silver nanoparticles showed maximum inhibition for the growth of fungal hyphae and conidial germination in in vivo tests. Scanning electron microscope results indicated that the silver nanoparticles caused detrimental effects on both mycelial growth and conidial germination.

Statistical Analyses of Clinical Cases of Skin Lesions from Agricultural Chemicals in Japanese Farmers, 1982-1989 / 日本農村医学会雑誌

Statistical analyses were made on a total of 242 clinical cases of skin disordersfrom agricultural chemicals in Japanese farmers, using data recorded by physicians on standard forms in 41 hospitals and other medical institutions during the 1982-89 period. The majority of the cases were acute dermatitis (72.3%), followed by chronic dermatitis (19.0%), chemical burns (7.4%) and photosensitive dermatitis (2.1%). Organophosporus insecticides were the most frequent inducer of occupational skin lesions (24.8%), followed by sulfur fungicides (20.7%), polyhaloalkylthio-fungicides (16.1%), and soil disinfectants (7.9%). Main factors contributing to the onset of skin lesions were insufficient clothing on the part of users (46.7%), carelessness (21.9%), unsuitable weather (strong wind) (9.9%) and so forth. Epidemiological features such as sex, age, season, complications, affected sites and prognoses were also analyzed and discussed.

Statistical study of clinical cases of skin disorder from agricultural chemicals in Japanese farmers, 1972-1981 / 日本農村医学会雑誌

A total of 630 clinical cases of occupational skin disorder from agricultural chemicals werestatistically analyzed in Japanese farmers who were recorded by physicians on a standard form from41 hospitals and other medical institutions during the 1972-81 period. The majority of the cases wereacute dermatitis (66.7%). This was followed by chronic dermatitis (24.3%), chemical burns (8.4%) andphotosensitive dermatitis (2.2%). By type to chemicals, the number one skin hazard was sulfurfungicides (32.2%), followed by organophosphorus insecticides (28.6%), polyhaloalkylthio-fungicides (11.4%), and copper fungicides (7.1%). Factors contributing to the onset of any disorder of the skinwere mainly defenseless on the part of users (41.3%), carelessness (20.2%), poor health condition(14.6%), and so forth. Other epidemiological features by sex, age, season, complications, sites of skindisorder, prognosis, etc. were also analyzed and discussed.