Original Articles
R Ramkumar, BK Nayak and A Nan
Abstract
Soil mycoflora play an important role as major decomposers in the soil ecosystem. They also provide mankind with very useful pharmaceutical products, such as antibiotics and other valuable substances, including organic acids, enzymes, pigments and secondary metabolites used in the food industry and fermentation. In addition, many soil fungi are biological control agents for plant pathogens and insect pests and some of them are very harmful causing food spoilage and diseases to plants, animals and humans with significant economic losses and produce mycotoxins in certain products. In the recent study, soil samples of two different fields viz, Paddy field and Garden land were studied to record the incidence of fungal composition and their diversity. Aspergillus terreus was found as the dominant one in paddy field soil but Penicillium citrinum was the dominant one in garden soil. The results obtained clearly indicated that Aspergillus terreus, Aspergillus niger, Aspergillus flavus and Penicillium digitatum, Trichoderma were of high occurrence in both the land soils and some other fungi like Fusarium, Chaetomium sp., Curvularia and Paecillomyces spp were negligible. Among the isolates Aspergillus and white sterile mycelia were dominant in all agricultural fields due to high sporulation capacity and the Penicillium spp were producing fungal and bacterial antibiotics and the Aspergillus spp producing different kinds of toxins such as aflatoxin and ochratoxin etc. These toxins may prevent the growth of other fungal species. The frequency of mycoflora in agricultural fields were found to be regulated by many factors like temperature, humidity, vegetation, organic and inorganic materials, soil type and texture. The fungi were mostly observed in months of June to September due to suitable temperature and humidity.