Ecology and biotechnology of thermophilic fungi on crops under global warming

Abstract

This chapter considers how global warming will change fungi in the environment to those that grow at high temperatures. Biotechnology will be affected (a) positively, by creating thermotolerant and thermophilic fungi (TTF), which have novel applied properties, and (b) negatively, in that useful fungi may disappear. The chapter indicates how this could happen and what the novel properties may be. Overall, the purpose is to increase awareness of the issue of global warming changing the paradigm and pointing out the potential loss of the current diversity of fungi with biotechnological potential. The change in fungi that is occurring now is well illustrated by mycotoxigenic fungi. Underpinning the diversity of fungi is correct nomenclature which is discussed. A major threat from certain fungi is mycotoxin contamination of crops, which are known agents of diseases for humans and animals. Plant diseases of crops in general are frequently caused by fungi. Climate change will lead to more extreme climate and an increase in temperature is predicted in which many fungi will adapt to grow. The higher temperatures are leading to increases in aflatoxin contamination of crops which are the most dangerous mycotoxins. Crops will be challenged severely threatening the sustainability of the human food supply. However, by extension, temperatures are likely to go beyond the optimum growth for aflatoxigenic fungi which could become extinct in tropical regions with high aflatoxin contamination in food. Succeeding thermotolerant and thermophilic fungi (TTF) may produce novel mycotoxins. Fungi with useful biotechnological properties (e.g. pharmaceuticals, enzymes, organic acids) found in the environment could be lost or found. The only conventional mycotoxin produced by TTF is patulin; and could this mycotoxin dominate aflatoxin? In addition, TTF may increase diseases of tropical plants as illustrated with Ganoderma disease of oil palm, the plant that produces valuable palm oil. The TTF may have unique biotechnological properties such as the ability to produce high-temperature enzymes. Novel white rot fungi may evolve from the Ganoderma fungi that rot oil palm, leading to novel lignocellulose-degrading enzymes capable of operating at high temperatures. The results of this current work indicated that novel opportunities may arise for biotechnology with climate change although the overall effect will be detrimental to areas related to plant pathology. The chapter considers the ecological and biotechnological implications of these possibilities.