Optimization of the cultivation conditions for mushroom production with European wild strains of Agaricus subrufescens and Brazilian cultivars.

BACKGROUND: The almond mushroom Agaricus subrufescens (formerly Agaricus blazei or Agaricus brasiliensis) is cultivated at commercial level in Brazil and some Asian countries on local substrates and casing mixtures. Despite its tropical origin, A. subrufescens might be a seasonal option for mushroom growers in western countries, where some wild strains have been isolated. For this purpose, cultivation conditions were developed starting from the substrate and casing mixture commonly used for commercial production of the button mushroom Agaricus bisporus in France. RESULTS: The commercial compost, based on wheat straw and horse manure, used for A. bisporus and the casing mixture (peat and limestone) supplemented with fine sand proved efficient to grow A. subrufescens. Increasing the depth of the casing layer improved significantly the yield and time to fruiting. Daily variations in temperature did not markedly modify the yield. Significantly higher mushroom biomass was obtained with three wild European strains compared with three Brazilian cultivars. The very productive wild strain CA438-A gave mushrooms of size and dry matter content comparable to those of a cultivar. CONCLUSION: Commercial production of A. subrufescens can be developed in western countries on the wheat straw-based substrate commonly used for A. bisporus in these regions, by a simple modification of the casing mixture and maintaining the incubation temperature throughout the crop, which is expected to save energy during summer. Good yields were obtained cultivating European strains under optimised parameters.

Potential of European wild strains of Agaricus subrufescens for productivity and quality on wheat straw based compost.

The Brazilian almond mushroom is currently cultivated for its medicinal properties but cultivars are suspected all to have a common origin. The objective of this work was to assess the potential of wild isolates of Agaricus subrufescens Peck (Agaricus blazei, Agaricus brasiliensis) as a source of new traits to improve the mushroom yield and quality for developing new cultures under European growing conditions. The wild European strains analysed showed a good ability to be commercially cultivated on wheat straw and horse manure based compost: shorter time to fruiting, higher yield, similar antioxidant activities when compared to cultivars. They have a valuable potential of genetic and phenotypic diversity and proved to be interfertile with the original culture of the Brazilian almond mushroom. Intercontinental hybrids could be obtained and combine properties from both Brazilian and European germplasm for increasing the choice of strains cultivated by the mushroom growers.

The medicinal Agaricus mushroom cultivated in Brazil: biology, cultivation and non-medicinal valorisation.

Sun mushroom is a cultivated mushroom extensively studied for its medicinal properties for several years and literature abounds on the topic. Besides, agronomical aspects were investigated in Brazil, the country the mushroom comes from, and some studies focus on the biology of the fungus. This review aimed to present an overview of the non-medicinal knowledge on the mushroom. Areas of commercial production and marketing trends are presented. Its specific fragrance, taste, nutritional value and potential use of extracts as food additives are compared to those of the most cultivated fungi and laboratory models. The interest of the mushroom for lignocellulosic enzyme production and source of biomolecules for the control of plant pathogens are shown. Investigation of genetic variability among cultivars is reported. Growing and storage of mycelium, as well as cultivation conditions (substrate and casing generally based on local products; indoor and outdoor cultivation; diseases and disorders) are described and compared to knowledge on Agaricus bisporus.