Antifungal activity of homeopathic medicines against the white mold causing agent Sclerotinia sclerotiorum

White mold disease, caused by fungus Sclerotinia sclerotiorum (Lib.) de Bary., is a disease hard to control due to the high amount of sclerotia produced, which guarantees its survival in the soil for years leading to significant yield losses. Alternative techniques to control the pathogen have been researched, including homeopathy. The present work aimed to evaluate the in vitro antifungal effect of homeopathic medicines on S. sclerotiorum mycelial growth. Homeopathic medicines Sulphur, fungal sclerotium Nosode and Calcarea carbonica, in 30CH, 200CH and 1000CH dynamizations were tested. Assays were carried out in a completely randomized design, with four repetitions. Experiments were performed through the addition of homeopathic medicines on the surface of plates containing culture medium, followed by insertion of a disc containing fungus mycelia and incubation. Control treatment received no homeopathic medicine. The mycelial progression was monitored by seven halo diameter measurements during experiment period. All homeopathic medicines tested and their dynamizations were able to inhibit partially the development of the fungus. Calcarea carbonica at the dynamization of 1000 CH showed the best inhibitory effect on S. sclerotiorum, which under its effect produced a mycelial halo 40% smaller than the control treatment.

First report that Mucor irregularis causes white mold disease on substrates used for wine-cap mushroom (Stropharia rugosoannulata) cultivation in China

Stropharia rugosoannulata, a world-wide popular mushroom, is one of the edible fungi recommended by the Food and Agriculture Organization of the United Nations (FAO) to developing countries (Hawksworth et al., 1996). In China, the cultivation scale of S. rugosoannulata exceeded 40 km2 in 2020 according to the incomplete statistics from emushroom network (http://www.emushroom.net/news/202104/06/33499.html). In October 2020, white mold disease was found on substrates of S. rugosoannulata in a heliogreenhouse in Huai’an city, Jiangsu province, China (Figure 1). The cultivation materials of S. rugosoannulata included rice straw (30%), wheat straw (30%), saw dust (30%), and a small amount of wheat bran (5%) and rice bran (5%). After mixing them together, the mycelial strain of S. rugosoannulata was seeded into the mixture, and then covered by casing soil for further cultivation. In the heliogreenhouse, the average air temperature and relative air humidity were 18 ± 4℃ and 73 ± 3%, respectively. In the diseased substrates, a large amount of thick white fungal mycelia were observed with yellow ooze on the surface, which prevented the growth of the mycelia and fruiting bodies of S. rugosoannulata (Figure 2). However in the fruiting period, no disease symptoms were found on mature fruiting bodies of S. rugosoannulata. The white mold disease incidence was calculated as ~ 30% by dividing the total infected area of substrates with the total area of the substrates examined. This white mold disease resulted in serious economic losses due to reduced production.

White-rot fungus: an updated review

The White Fungus, which causes white rot on tree trunks, belongs to the basidiomycetes. Research into the microbiology of White-rot fungi has focused on engineering processes related to factors such as cell growth and enzyme production processes, and to smaller, i.e., molecular biology. Many studies have been conducted to select issues with high or specific biodegradation performance in a variety of ways. Production inhibitors have been used to improve enzyme production. Investigators are investigating different carriers (Stainless Steel net, polyamide fiber net, fiberglass net and polyurethane foam) to impair P.chrysosporium ligninolytic enzyme production. In this review, Pathophysiology, Microbiology, impact factors, treatments and alternative uses show white mold formation in biotransformation. The white fungus is being investigated to produce biotechnology for the reduction of a broad spectrum, a natural pollutant based on lignin-deficient enzymes. This in particular covers the destruction of many wastes and environmental pollution, including wastewater, pesticides, toxic natural pollutants, chlorinated hydrocarbons, etc. It will be updated.

Comparing the Fungicide Sensitivity of Sclerotinia sclerotiorum Using Mycelial Growth and Ascospore Germination Assays

The infection of the floral tissues of snap bean and other crops by Sclerotinia sclerotiorum, the causative agent of white mold, is by ascospores. Irrespective of the fungicide mode of action being evaluated, in vitro fungicide sensitivity tests are conducted almost exclusively using mycelial growth assays. This is likely due to difficulties and time involved in sclerotial conditioning required to produce apothecia and ascospores. The objective of this research was to compare estimates of fungicide sensitivity between mycelial growth and ascospore germination assays for S. sclerotiorum. Sensitivity assays were conducted using serial doses of three fungicides commonly used to control white mold: boscalid, fluazinam, and thiophanate-methyl. A total of 27 isolates were evaluated in replicated trials conducted for each fungicide and assay type. The effective concentration to reduce mycelial growth or ascospore germination by 50% (EC50) was estimated for each isolate, fungicide, assay type, and trial. The median EC50 values obtained from ascospore germination assays were 52.7, 10.0, and 2.7 times higher than those estimated from the mycelial growth for boscalid, fluazinam, and thiophanate-methyl, respectively. No significant correlation was found between EC50 values estimated by the two methods. These findings highlight differences that may be important in evaluating the sensitivity of S. sclerotiorum given the fungicide mode of action and how they will be used in the field.