Lentinula edodes Cultivation Techniques and Models in China
Tan Qi, Shang Xiaodong, Zhang Lujun, Li Yu, Yu Hailong, Zhou Feng,
Zhang Meiyan, Song Chunyan
Institute of Edible Fungi, Shanghai Academy of Agricultural Sciences, Shanghai, China
Lentinula edodes has been a major contributor to the vigorous development of China’s edible fungi industry, with the widest production area, highest total output and the most profitable economic returns. In 2014, the total output of L. edodes in China reached seven million tons, accounting for approximately 80% of production worldwide. L. edodes is a traditional food in oriental countries, beloved especially by consumers in China, Japan and Korea.
Cultivation of L. edodes originated in China, dating back over 800 years, and its development can be divided into three important phases: ‘hatchet-notching’ cultivation, cut-log cultivation and artificial cultivation. ‘Hatchet-notching’ cultivation is a semi-artificial method in which a hatchet was used to make cuts in felled broadleaf tree trunks and relied on wild L. edodes spores (‘spawn’) floating down with the wind to inoculate the cuts and ultimately lead to fruit body formation. A relatively primitive technique, L. edodes yields depended very much on the density and quality of the L. edodes spores in the natural environment and on the local climatic conditions.
‘Hatchet-notching’ cultivation method
When, during the last century, the Japanese scholar Hikosaburō Morimoto isolated a pure strain of L. edodes, production of this mushroom in China moved from the ‘hatchet-notching’ method to the artificially inoculated cut broadleaf-wood log cultivation technique. Introduction of this method into China necessitated adoption of a centralized manual management system in areas suited to L. edodes growth after pure L. edodes strains had been artificially inoculated into logs cut from fallen broadleaf trees. The cut-log procedure represented a technological revolution in L. edodes cultivation and unified both natural and artificial methodology. Not only did this technique shorten the length of the L. edodes cultivation cycle, it also led to substantially increased mushroom yields. A major drawback, however, was that it consumed huge amounts of forest resources and threatened ecological stabiliy. In 1978, a research team composed largely of scientific and technical personnel from the Shanghai Academy of Agricultural Sciences (SAAS) developed the sawdust brick system for cultivating L. edodes. This system was focused on the use of an artificial substrate formulation based on sawdust waste, inoculated aseptically with a pure mushroom strain, and careful management of the growth facility. It reduced the demand for wood resources typified by the cut-log procedure, eliminated geographical restraints previously applicable to L. edodes cultivation, facilitated the expansion of L. edodes production from remote forest regions to more easily accessible lowland areas, greatly improved biological efficiency, and represented another significant technological revolution.
‘Cut-log’ cultivation method
‘Sawdust brick’ cultivation method
In 1983, inspired by the ‘bag’ cultivation of Tremella fuciformis, Zhaowang Peng and others from Gutian County, Fujian Province, modified the sawdust brick technique and developed the sawdust bag for cultivating L. edodes. After popularization, this technique rapidly superseded the cut broadleaf-wood log cultivation technique and resulted in L. edodes cultivation expanding rapidly to all provinces in China southward from the Yangtze River Basin.
As a consequence of this unceasing expansion, diverse cultivation models, and varieties suited to climatic conditions in different regions and to different cultivation traditions have emerged. Principal L. edodes artificial cultivation systems operating in the major producing areas include the ‘shelf’, ‘bag-on-the ground’ and ‘soil-covering’ models.
‘Sawdust bag” (artificial log) cultivation method
However, due to China’s fast economic growth in recent years, problems have arisen with the small-scale, family-oriented L. edodes cultivation model. It is a heavily labour-intensive production process with only a low level of mechanization, year-round production cannot be sustained due to the seasonal production cycle, product quality is often unstable, and there is a limited capacity on the part of growers to resist fluctuations in market prices. Currently, an intensive cultivation model based on specialization and division of labour has been adopted in China’s main L. edodes production areas which, compared with the traditional model, ensures the safety and security of the raw materials used for cultivation, and lends itself to increased mechanization. Standardized spawn production, inoculation procedures, spawn-running and other management practices have helped to ensure higher yields, and integrated L. edodes product collection and distribution has served to reduce the risks associated with market price fluctuations. However, the intensive L. edodes cultivation model requires more careful supervision and stronger technical support, especially in the control of spawn quality.
Nevertheless, the intensive L. edodes cultivation model is still limited to seasonal production. Therefore, in order to ensure an all-year-round supply of fresh L. edodes, an industrialized cultivation model has emerged, and the development of a technological process with Chinese characteristics is in progress. After three years of exploratory work, researchers at the SAAS have proposed an ‘industrial-scale production technology for L. edodes based on secondary culture’. Using special L. edodes strains, this model has adopted the concept of ‘spawn running in the bottle, fruiting by means of briquetting’. The two-stage procedure combines the automated conversion of the colonized cultivation substrate from the culture bottles into briquettes for subsequent brown film formation and fruiting. While existing L. edodes industrial-scale production models operating in Japan and Korea require special equipment and materials, this new Chinese model allows for more automation to be introduced in the production line at lower cost, thereby greatly reducing the probability of contamination inherent in ventilated bag cultivation, and will make it easier to achieve a fully mechanized system for large-scale L. edodes production.
‘Bag on ground’ mode
‘Soil covering’ mode
In the light of current developments, family-oriented production models for L. edodes will eventually be eliminated, and fully automated industrial systems involving intensification and division of labour based on specialization will become the main L. edodes cultivation model in China in the future.
The WSMBMP Bulletin is the official electronic publication of the World Society for Mushroom Biology and Mushroom Products. The bulletin is intended to keep members informed about Council activities and to share general information about mushrooms. It is designed to allow communication between society members and alert them about new topics and opportunities related to mushrooms. Society members and general public are kindly invited to submit letters, comments and information of interest for the mushroom community to be published in the bulletin. Please submit your contributions electronically in free format to the editors José E. Sanchez
firstname.lastname@example.org, John Buswelljabuswell2003@yahoo.co.uk, Daniel J. Royse
Helen Grogan email@example.com.
back to the beginning