Kingdom Fungi: The Fungi are by far the largest group of fungi. The name Eumycota has been used for the same group, with “-mycota” at the end, which indicates the rank of division. This taxonomic level, however, is used to name groups within the Fungi, so “Fungi” is the preferable term for the kingdom of true fungi.

Kingdom Fungi

Most fungi are heterotrophic and absorb soluble organic matter from dead substrates and hence are called saprophytes. Those that depend on living plants and animals are called parasites. They can also live as symbionts – in association with algae as lichens and with roots of higher plants as mycorrhiza.

Following are the important characteristics of Kingdom Fungi:

• Fungi are eukaryotic, non-vascular, non-motile and heterotrophic organisms.
• They may be unicellular or filamentous.
• They reproduce by means of spores.
• Fungi exhibit the phenomenon of alternation of generation.
• Fungi lack chlorophyll and hence cannot perform photosynthesis.
• Fungi store their food in the form of starch.
• Biosynthesis of chitin occurs in fungi.
• The nuclei of the fungi are very small.
• The fungi have no embryonic stage. They develop from the spores.
• The mode of reproduction is sexual or asexual.
• Some fungi are parasitic and can infect the host.
• Fungi produce a chemical called pheromone which leads to sexual reproduction in fungi.
• Examples include mushrooms, moulds and yeast.

Economic importance of Kingdom Fungi

A. Harmful Fungi
Several agricultural plants like sugarcane, maize, cereals and vegetables suffer from diseases caused by fungi.

1. Puccinia graminis (Wheat Rust) It causes brown patches on leaf and stem of wheat plants. It decreases the yield of wheat and makes it unfit for human consumption.

2. Rhizopus or (Bread Mould) grows on bread . If the bread is exposed to warm and humid conditions a cottony mass develops in few days. This white cotton mass later develops a greyish black colour, because of black coloured spores.
– The whitish network is called mycelium.
– The mycelium contains thread like structures called hyphae.
– The root-like sturctures growing out of the hyphae penetrate the bread, and secrete digestive enzymes (extracellular digestion) and absorb the digested food.
– Greyish black colour of the mould develops due to formation of sporangium which after rupturing release dark coloured spores. The spores scatter by wind and germinate after falling on a suitable substractum. This is asexual
reproduction.

B. Beneficial Fungi
– Certain Mushrooms (such as Agaricus campestris) are edible. Yeast is used for fermentation during manufacture of bread, beer, soya sauce, cheese and wine.
– Mycorrhizae are fungi associated with roots of plants. Roots benefit in getting minerals from the environment while fungi get food from the plant in return through such association.
– Neurospora has been a favourite experimental material in Genetics.
– Various antibiotics are derived from fungi. Penicillin is obtained from Penicillium notatum . Its antibiotic effect was discovered by chance by Alexander Flemming in 1927.

Follow on Facebook

By Team Learning Mantras