Fungi and Lichens

Fungi are among the most primitive members of the plant kingdom. Study of the fungi is called mycology. The fungi are non-chlorophylous, nucleated, non-vascular, thallophytic micro organism and due to lack of chlorophyll they do not prepare their own food. The fungi are among the thallophytes or plants with a thallus, which are simple plants, have no roots, stems, flowers and seeds- structures we commonly associate with higher plants. The thallus of a fungus is usually made of branching threads called hyphae.

Why Photosynthesis does not take place in Fungi?

Fungi lack chlorophyll and cannot prepare their own food and depend on other organism for nourishment. On the basis of nourishment the fungi are of three types –

  • Saprophytes: The fungi which obtain their food or do nutrition from decayed moist leaves, moist dead wood or by some other useless rotten residues or organic substances. The fungi like Rhizopus, Penicillium etc are saprophytes.
  • Parasites: The fungi which obtain their food by taking or sharing  the food of any other organisms. The fungi like Ustilago, Puccinia etc that are harmful parasites.
  • Symbiotic: The fungi, which coexist with other plants and facilitate water and mineral salt and plants prepare food for them. The microbe lichen is the best example of symobiotic fungus.

Benefits of Fungi

Soil Formation and Fertility

The fungi decompose moist residues of leaves, dead wood, animal along dung and other rotten organic substances into another, which act like manures, and thus soil becomes more fertile.

Food

There are various fungi which are used as food. Agaricus and Morchella are used in the forms of vegetables (mushrooms) fungi. Aspergillus, penicillium are used in cheese industry, yeast a (a type of fungi) like Saccharomyces cervisiae is used in making double roti (bread dough). Wines, beers are also prepared by the alcoholic fermentations of the yeasts.

Nitrogen fixation

The fungi like Rodoturela do the process of nitrogen fixation due to which the fertility of the soil is enhanced.

Medicines

In the fungi  there are various types of antibiotics which are utilized in making medicines like chloromycetin, neomycin, streptomycin, teramycin etc.

Chemical Industry

Various types of acids and chemical substances are prepared. Aspergillus gallomyces and Pencillium glaucum are used in the Gallic acid. Similarly Gluconic acid and Fumeric acid are prepared by the fungi Aspergillus niger and Rhizopus nigricans respectively.

Enzymes and Vitamins

By the fungi and some yeast, various types of enzymes are prepared. The enzymes amylase is prepared from Aspergillus orizae. Similarly, invertase is prepared by yeasts.  Various vitamins like vitamin B is prepared from Streptomyces griseus.

Mycoremediation

Bioremediation by means of Fungi is called Mycoremediation. Fungi have been shown to biomineralize uranium oxides, suggesting they may have application in the bioremediation of radioactively polluted sites. Some fungi are hyperaccumulators, capable of absorbing and concentrating heavy metals in the mushroom fruit bodies.

Pest control

Beauveria bassiana, Metarhizium spp, Hirsutella spp, Paecilomyces (Isaria) spp, and Lecanicillium lecanii have been used in Pest Control. One gene-one enzyme hypothesis was formulated by scientists who used the bread mold Neurospora crassa to test their biochemical theories. Aspergillus nidulans and the yeasts, Saccaromyces cerevisiae and Schizosaccharomyces pombe, have a long history of use to investigate issues in eukaryotic cell biology and genetics, such as cell cycle regulation, chromatin structure, and gene regulation.

Common fungal diseases

Wart disease of potato, Late blight of potato, Green ear disease of bajra, Rust of wheat, Loose smut of wheat, Tikka disease of groundnut, Red rot of sugarcane, Brown leaf spot of rice, Ergot disease of rye, Powdery mildew of wheat etc.

Common animal and human fungal diseases include Athlete’s foot scabies, Scabies , Ring worm, Meningitis, Asthma, Baldness, Aspergillosis etc.

Lichens

Lichens are symbiotic associations of fungi and algae. In this association, the fungi (called mycobiont) facilitate water, minerals, vitamins, etc to the algae and algae (called phycobiont) prepare carbohydrate by the process of photosynthesis and supply the food to the fungi. Study of lichens is called Lichenology. Lichens are most commonly found on the trees. Lichens are useful and by the help of these various economic activities can be observed. Lichens are capable to indicate air pollution, water pollution, heavy metals as well as radioactive particles. Lichens like Reindeer mosses, Iceland moss etc are utilized as food stuffs.


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