why fungi are grown in humus-rich substrata ?
Fungi are saprophytic in nature. They utilize the organic matter present in the substratum. Humus is a carbon-based, organic substance rich in organic matter. When fungi are grown in humus-rich substratum, they absorb their food in the form of nutrients from humus. During nutrient utilisation, the fungi secrete some extra-cellular enzymes which break down the complex compounds into simpler ones which can be easily absorbed the plants.
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