Production flush of Agaricus blazei on Brazilian casing layers

This study aimed to verify the biological efficiency and production flushes of Agaricus blazei strains on different casing layers during 90 cultivation days. Four casing layers were used: mixture of subsoil and charcoal (VCS), lime schist (LSC), São Paulo peat (SPP) and Santa Catarina peat (SCP); and two genetically distant A. blazei strains. The fungus was grown in composted substratum and, after total colonization, a pasteurized casing layer was added over the substratum, and fructification was induced. Mushrooms were picked up daily when the basidiocarp veil was stretched, but before the lamella were exposed. The biological efficiency (BE) was determined by the fresh basidiocarp mass divided by the substratum dry mass, expressed in percentage. The production flushes were also determined over time production. The BE and production flushes during 90 days were affected by the strains as well as by the casing layers. The ABL26 and LSC produced the best BE of 60.4 percent. Although VCS is the most used casing layer in Brazil, it is inferior to other casing layers, for all strains, throughout cultivation time. The strain, not the casing layer, is responsible for eventual variations of the average mushroom mass. In average, circa 50 percent of the mushroom production occurs around the first month, 30 percent in the second month, and 20 percent in third month. The casing layer water management depends on the casing layer type and the strain. Production flush responds better to water reposition, mainly with ABL26, and better porosity to LSC and SCP casing layers.

Mushroom cultivation in Brazil: challenges and potential for growth / Cultivo de cogumelos no Brasil: desafios e potencialidades

Mushroom cultivation is rapidly expanding in Brazil because Brazilians have discovered the medicinal and culinary value of mushrooms and their economic situation has improved. However, the horticultural technology for cultivating mushrooms under Brazilian conditions is lacking. For many years, the mushroom cultivation technology used in Brazil was adapted from developed countries whose materials and climate were different from those of Brazil. In order to exploit the Brazilian potential for mushroom cultivation it is essential to develop cultivation technology for family owned and operated rustic farms as well as for modern large scale industrial operations. Mushroom species cultivated in Brazil are discussed and some approaches for future research are suggested.

O cultivo de cogumelos está em franca expansão no Brasil, graças à descoberta de suas propriedades medicinais e culinárias pelo povo brasileiro e também em função da melhoria das condições econômicas. Entretanto, há ainda uma necessidade de desenvolvimento de uma tecnologia de cultivo apropriada para as condições brasileiras. Durante muitos anos, a tecnologia de cultivo de cogumelos utilizada no Brasil foi uma adaptação daquela utilizada nos países desenvolvidos, cujas condições climáticas e disponibilidade de matéria-prima são diferentes do Brasil. Portanto, para que se possa desenvolver todo o potencial brasileiro para o cultivo de cogumelos, é essencial o desenvolvimento de tecnologias de cultivo mais apropriadas para a agricultura familiar, mas também é importante o desenvolvimento tecnológico voltado para o cultivo de cogumelos em escala industrial. As principais espécies de cogumelos cultivados no Brasil são discutidas neste trabalho, além da indicação das principais necessidades de pesquisa para o futuro.

Effect of Casing Layer on Growth Promotion of the Edible Mushroom Pleurotus ostreatus

Various bacteria were isolated from the casing layer soil of the culture bed of P. ostreatus and their role in fruiting body induction of the edible mushroom, P. ostreatus, was investigated. Analysis of the bacterial community isolated from the casing layer soil revealed that the composition of genera and number of cultivable bacteria were different for each sterilizing treatment. Bordetella was predominant in the bulk soil whereas Flavobacterium was predominant after sterilization of the casing layer soil. Fluorescent Pseudomonas was predominant in the non-sterilized casing layer soil. Total number of the bacterial genera in the casing layer soil was higher than that in the bulk soil. In particular, an increase in the fluorescent Pseudomonas population was observed in the non-sterilized casing layer accompanied by induction of fruiting body and enhanced mushroom production yield. The results suggested that specific bacterial populations in the casing layer play an important role in the formation of primodia and the development of basidiome in P. ostreatus.

Isolamento e identificação de bactérias presentes nos solos de cobertura utilizados no cultivo do cogumelo Agaricus blazei Murril / Isolation and identification of bacteria present in the casing layer utilized to the cultivation of the mushroom Agaricus blazei Murril

Este trabalho foi desenvolvido com o objetivo de isolar e identificar bactérias presentes nos solos utilizados como camada de cobertura do cultivo de Agaricus blazei Murril. Foi avaliada a eficiência da desinfestação com vapor d'água e formol nos solos de cobertura. O tratamento com formol apresentou maior redução no número de bactérias na terra de barranco (Latossolo Vermelho distroférrico) e solo de pastagens (Latossolo Amarelo distrófico), enquanto que no solo hidromórfico, oriundo de várzea (Gleissolo Melânico), nenhum dos tratamentos foi eficiente para reduzir a comunidade microbiana. Foram identificadas bactérias do gênero Pseudomonas, Salmonella, Enterobacter e Shigella, dentre outras, denotando que os tratamentos de desinfestação não eliminam bactérias potencialmente benéficas, mas também não eliminam bactérias potencialmente patogênicas. Além disso, os tratamentos de desinfestação também não afetaram a produtividade do cogumelo A. blazei nas condições testadas.

The objective of this work was to quantify and to isolate the bacteria present in casing layer used for the cultivation of the Agaricus blazei Murril. It was evaluated the efficiency of the steam and formaldehyde disinfestation in the casing layer. The formaldehyde disinfestation showed a reduction of the bacteria population on the ravine soils (distroferric Red Latosol) and grazing land soil (distrofic Yellow Latosol), while in the hydromorphic soil coming from lowland (Melanic G]/leysol) none of the treatments used were efficient to reduce the bacteria population. Bacteria of the genera Pseudomonas, Salmonella, Enterobacter, Shigella, among others, were identified in all treatments analysed. It was observed that the disinfestation treatments did not eliminate neither potentially beneficial bacteria nor pathogenic bacteria. There was no significant effect of the disinfestation treatments on productivity of A. blazei mushroom. Moreover, the disinfestation treatments did not affect the productivity of the A. blazei in the studied conditions.