Influences of environmental factors on fruiting body induction, development and maturation in mushroom-forming fungi

• Published in: Fungal biology reviews Vol. 32; no. 4; pp. 236 - 248
• Main Author: Sakamoto, Yuichi
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.09.2018
• Subjects: Fruiting body; Gravity; Light; Nutrient; Senescence; Temperature; Nutrient; Senescence; Temperature; Light; Fruiting body; Gravity
• ISSN: 1749-4613; 1878-0253
• DOI: 10.1016/j.fbr.2018.02.003

Mushroom-forming fungi (restricted to basidiomycetous fungi in this review) differentiate by sensing several environmental factors for fruiting body formation. For fruiting body induction, nutrient, temperature and light conditions are critical environmental factors. Higher nitrogen and carbon sources in the media will suppress fruiting body induction in many mushroom-forming fungi, with induction being triggered by lower nitrogen and carbon concentrations. Low temperature or temperature downshift is another critical influencing factor for fruiting body induction in many cultivated mushrooms, such as Flammulina velutipes, Lentinula edodes, and Volvariella volvacea. Fungal response toward starvation and cold involves the production of sexual spores as the next generation. Species like F. velutipes and Coprinopsis cinerea can form fruiting bodies in the dark; however, light accelerates fruiting body induction in some mushroom-forming fungi. Remarkably, fruiting bodies formed in the dark have tiny or no pileus on heads (called dark stipe, pinhead fruiting body, or etiolated stipe). Light is essential for pileus differentiation in many, but not all mushroom species; one exception is Agaricus bisporus. Mushrooms have positive phototropism and negative gravitropism for effective dispersal of spores. Carbon dioxide concentrations also affect fruiting body development; pileus differentiation is suppressed at a high concentration of carbon dioxide. Thus, the pileus differentiation system of mushrooms may allow the most effective diffusion of spores. Full expansion of the pileus is followed by pileus autolysis or senescence. In C. cinerea, pileus autolysis occurs during spore diffusion. Fruiting body senescence, browning of gill, and softening occur after harvesting in several mushroom species. Fruiting body induction, development, and maturation in mushroom-forming fungi are discussed in this review. •Temperature and nutrient are critical factors on fruiting body induction.•Light promotes fruiting body induction in several mushrooms.•Mushrooms have anti gravitropism and positive phototropism.•Light is a critical factor on pileus development in many mushroom species.•Fruiting body senescence occurs after harvesting in many mushroom species.