ECONOMIC IMPORTANCE OF FUNGI

Economically fungi are very important because of their both harmful and beneficial effects –

1. HARMFUL EFFECTS OF FUNGI

i) Fungi are the chief agents responsible for the disintegration of fruits, vegetables and other food stuffs, e.g., jams, jelly, pickles, bread, various cooked foods etc. Common food spoiling fungi are Aspergillus, Penicillium, Mucor and Rhizopus.

ii) Fungi are also responsible for the diseases on plants and animals including human beings. Few species of Mucor, Rhizopus are common fungi affecting lungs, brain and gastric system. Neurospora and Fusarium infect corneal tissue of eye.

iii) Fungi are also responsible for various diseases which cause millions of rupees loss by damaging important crop plants.  Of the various diseases caused by fungi in plants are – blight and rot diseases of potato plant caused by Phytophthora infestans, downy mildew of Crucifers caused by Peronospora parasitica, rust diseases caused by the species of Puccinia, smut diseases caused by Helminthosporium, etc.

iv) Some fungi are toxic. Several toxins have been extracted from mushrooms like Amanita phalloides. Toxins of fungi fall into two groups – phallotoxins and amatoxins. Both the types of toxins are found to affect liver, stomach and intestine cells.

2. BENEFICIAL EFFECTS OF FUNGI

i) Many saprophytic fungi along with bacteria decompose the dead organic matters and thereby help in returning the nutrients to the soil in a form available to green plants. The large amount of CO₂ released by fungi during decomposition of organic matter is being used up by plants for the synthesis of their food.

ii) Various types of Yeast and few species of Penicillium are important industrially used fungi for the production of wines, beers, breads and the preparation of cheese, etc. They are also used in the production of organic acids, such as citric acid, gluconic acid, lactic acid, etc.

iii) Penicillin, one of the most important antibiotic is obtained from the two species of Penicillium i.e., P. notatum and P. chrysogenum, and is used against some bacterial infections. Simillarly, Streptomycin is the antibiotic obtained from Streptomyces griseus, and is used for the treatment of pulmonary tubercolosis.

iv) Fungi are also used in the production of enzymes, vitamins and hormones. Amylase is a well known enzyme produced from Aspergillus niger, and A. oryzae. Digestine, diastase , polyzyme, etc. are obtained from A. flavus. Saccharomyces cerevisiae are the source of vitamin B-complex and riboflavin. Gibberella fujikuroi is a source of a group of hormones used in the acceleration of the growth of different plants.

v) Various types of alkaloids are obtained and used as a medicine. The ergots of Cleviceps purpurea contains a number of alkaloids which is used for stopping haemorrhage after child birth.

vi) A few organic acids are obtained from fungi. Citric acid and gluconic acid are produced from Aspergillus niger. Rhizopus stolonifer is used for the preparation of lactic acid and fumaric acid.

vii) Some fungi specially, mushrooms (e.g. Agaricus compestris, A. bisporus) are used as human food. Some species under the genus Tuber, commonly known as truffles are largely used as food. Yeast cakes, produced from Saccharomyces cerevisiae contains high amount of proteins and are sold in the market as yeast cakes.

viii) Fungi are also important from the view point of academic studies. Fungi are of concern not only to the pathologist, but also to the geneticists, cytologists and biochemists.

ix) Some fungi such as Arthrobotrys musiformis, Dactylaria thaumasia, etc. feed on parasitic amoebae, nematodes, etc. and control the soil borne pathogens. Such fungi are used in large scales for controlling soil borne pathogens.

            x) Some fungi such as Boletus, Phallus, etc. live in symbiotic association with the roots of higher plants, thereby producing abundant nutrients, which can be used up by the roots of higher plants and enhance growth.

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