In rainy season, you must have seen the growth of soft, white, cottony and velvety patches of mould on stale bread, pickles, damp cloth, leather, food, leaves, fruits and vegetables. These are called fungi and are classified flowerless plants having no roots, no stems and no leaves and are without chlorophyll – the green colouring matter. Due to the lack of chlorophyll, fungi depend for their food either on a living organism (parasite) or on the dead organic matter (saprophyte). When we examine the fungi under a microscope, we see that they consist of a large number of black, green, yellow or blue fibres. These fibres have two parts – one part is mycelium which spreads like roots and takes food from the material on which it grows. The other part is round, ball-like lymph, which contains spores. Always present in the air, they start multiplying whenever they get bread, fruits and other eatables in hot and humid places.
Fungi feed on dead plants or vegetable matter. There are various kind of fungi: mushroom, mucor, mucedo (on bread), yeast, Penicillium, mildus, rusts, blight etc.
They are both useful as well as harmful for us. The biggest advantage of fungi is that they destroy and eliminate useless organic matter by setting decay in them. The matter decomposes into oxygen, nitrogen, carbon, phosphorus etc. and they spread in the atmosphere. They also help in preparing bread, beer, wine and cheese; in making organic acids, enzymes, vitamins and antibiotics. Penicillin which is useful in curing many diseases is prepared from the green-blue fungus called Penicillium. Yeast is also a fungus, used in fermentation process. Some varieties of fungi like mushroom, gorrils, trafills etc. are used as food. Some mushrooms are poisonous hence care should be taken while eating them.
However, on the other hand, some of the fungi cause diseases in plants and trees and destroy crops of potato, apple, etc.