Utilization of psychrotolerant phosphate solubilizing fungi under low temperature conditions of the mountain ecosystem

Abstract

The use of bioinoculants, in recent times, has received greater attention largely due to increased preference for the natural organic products across the globe, as well as to reduce the load of synthetics. One of the prerequisites for developing a microbe-based technology is proper understanding of the diversity of microorganisms in any given ecosystem with particular reference to their function and efficiency. Microorganisms play a fundamental role in the biogeochemical cycling of phosphorus in the natural ecosystems. Temperature, pH and biomass are important factors for such microbial activities. Since phosphate solubilization, and thereby making it available to plants, is pivotal for growth, the critical importance of phosphate solubilizing microorganisms is self evident. While microorganisms are ubiquitous in nature, their distribution is largely governed by environmental and edaphic specificities. Several species of fungi, belonging mainly to Aspergillus, Paecilomyces and Penicillium, survive and dominate in low temperature environs of the Indian Himalayan Region (IHR). Occurrence of such fungal communities is likely to mediate important ecological function in low temperature environments, generally associated with low nutrient status and low decomposition rates. The phosphate solubilization efficiency of various species of the three fungal genera, isolated from the Himalayan soils, has been investigated in some detail. The experiments were performed to examine their phosphate solubilization potential with particular reference to a number of associated factors, such as temperature, pH, biomass production, and the role of phosphatases. The findings are likely to have implications in respect of the possible applications of cold tolerant microbial communities in environment management, with reference to mountain ecosystems.