(a) Role of fungi in Agriculture or crop production
- Decomposition and humus formation: Fungi decompose the dead animals and plants. Fungi change them into humus. rums is decomposed organic matter. It plays an important role in germination of plant. It provides important nutrient to plants. Humus also holds the soil particles. Thus it reduces the chance of soil erosion. Humus also increases the water holding capacity of soil.
- 9iological succession: Fungi are important part of lichens. Lichens play an important role in biological succession They make barren land suitable for cultivation.
- Biological nitrogen fixation: Lichens are also involved in biological nitrogen fixation. They fix the atmospheric nitrogen to form nitrates. These nitrates are absorbed by the plants. Some fungi are also involved in free biological nitrogen fixation.
- Role of mycorrhizae: Mycorrhizae is an association between fungi and roots of higher plants. It has great survival value for plants. Fungi spread in large area around the plants. It absorbs water and minerals and transports them to plant. Thus plants can survive in arid conditions.
- .Thmmercial cultivation of fungi: Some fungi are edible. They are commercially cultivated in many countries. Some fungi like morels and truffles are very delicious. There is a great demand of these fungi in the market. Many countries are earning huge foreign exchange by exporting these fungi.
- Fungi as insecticides: Some fungi attack insects. They kill the insects. For example, fungi are used to kill the wheat bulb flies in USA.
- Source of plant hormones: Some fungi are source of plant hormones. Plant hormone gibberellins are obtained from Gibberella.
- ‘Wood rotting: Some fungi are involved in wood rotting. These fungi cause rotting of standing trees and lumbers.
- Diseases causes by fungi: Fungi cause very serious diseases in plants. They have caused many famines in the history of man. Some of diseases are:
(a) Rust and Smuts: These diseases have caused extensive damages • in wheat, corn and rice crops. So it has caused massive
displacement, starvation and death of many people.
(b) Powdery mildew on grapes, rose, wheat etc.
(c) Ergot of rye Red rots of sugar cane
(d) Potato wilt
(e) Cotton root rot
(f) Apple scab
(g) Brown rot in peaches. plums, apricots and cherries.
(b) Industrial application: Role of fungi in food and industry
- Edible fungi: Certain fungi are edible. About 200 species of mus’irooms (Agaricus sp.) are used as food. For example: Morels: e.g. Morchella esculenta. Truffles: Underground fruiting bodies of som Ascomycetes, e.g. Tuber sp).
- Use in baking and brewing industries: Yeasts can cause fern entation. So yeasts (Saccharomyces cerevisiae) are used in procuction of bread and liquor.
- :he se preparation: Pencillium species are used for giving flavour, aroma and characteristic colour to some cheese.
- ioya products: Some species of Aspergillus are used for fermenting and producing soya sauce and soya paste from soya bear s.
- Synthesis is of organic acids: Citric acid is obtained from some Asp.frgillus species. Some fungi yield fumaric acid and lactic acids.
- Source of vitamins and enzymes: Saccharomyces cerevisiae is a so.irce of vitamin B. vitamin D and riboflavin. Some enzymes like diastase. pectinase also obtained form fungi.
- Antibiotics and other drugs: Some fungi are source of antibiotics and other drugs.
(al Penicillin was first antibiotic. It was discovered by A. Fleming in 1928. Penicillin is obtained from Pencillium notatum.
(b) Lovastatin is used for lowering the blood cholesterol.
(c Cyclosporine is obtained from soil fungus. It is used in organ transplantation (like kidney). It prevents the transplant rejection.
(d) Ergotine is used to relieve headache by migraine.
(e Griseofulvin is used to inhibit fungal growth.
- Natural dyes: Some natural dyes are obtained from lichens. These are used in textile industry.